BIO

CHAPTER 2

Domains of Life

Archaea

Has a cell wall and branched lipids in membranes

Bacteria

Shapes:

a. Cocci
b. Bacilli
c. Spirillum
d. Streptococcus
e. Staphylococcus
f. Sarcina
g.Spirochetes

Cell Structures:
*not present in all*

Motility Structures

Flagella: structure that assists in
swimming (also in archaea)

Structure: tiny rotating machine,
long thin appendages; helical shape

Increase/decrease rotational speed
relative to strength of proton motive
force

Parts: Motor, hook, and filaments

Cellular components:

Gas Vacuole: buoyancy, decreases cell density

Ribosomes: a cellular structure composed of proteins and RNA at which new proteins are synthesized

Periplasmic space: contains hydrolytic enzymes and binding proteins for nutrient processing and uptake

Endospores: original cell copies its
chromosome and surrounds its self with a copy

1) Vegetative cell converted to non-growing, heat resistant, light refracting structure
2) GRAM positive
3) Only occurs when growth ceases due to lack of essential nutrients such as carbon/nitrogen
4)When conditions are fine the endospore will re-hydrate and resume functioning

Nucleoid: space containing the genetic information

Cell Surface Structures:

Peptidoglycan Layer: a polymer layer
composed of modified sugars cross-linked
by short polypeptides

Made with N-Acetylmuramic acid and N-Acetylglucosamine

Gram Stain: Technique that helps
categorize bacteria based on cell
wall compositions

Gram negative: thin peptidoglycan layer,
with a LPS outer layer

Gram positive: thick peptidoglycan layer

Cell Wall: gives bacteria shape and protection from lysis in diluted solutions

Capsules: sticky layer of polysaccarides or protein

Protects against dehydration, and protect
against immune defense systems

Fimbriae: hair like appendages

1) Enables organisms to stick to surfaces or form pellicles (thin sheets of cells on a liquid surface)
2) Short: ~2-10nm wide

Pili: Typically longer and few found
per cell than fimbriae

Conjugative pili facilitate genetic exchange between cells

Eukarya

Cell Structures

Cell components

Plasma Membrane: phospholipid bilayer that forms the outer boundary of any cell; regulator

Organelles: a discrete, membrane-enclosed cytoplasmic structure with a specific function

Vesicle: a small, membrane-enclosed sac found in cytosol

Lysosomes: a specialized vesicle with an acidic acid lumen containing enzymes that breakdown macromolecules

Vacuole: a water filled sac that serves various functions, including transport, structural support, and isolation of waste and harmful material

Peroxisome: contains enzymes that transfer hydrogen (H2) from various substrates to oxygen (O2) producing and then degrading hydrogen peroxide (H2O2)

Ribosome: a cellular structure composed of proteins and RNA at which new proteins are synthesized; can be either attached to the endoplasmic reticulum (ER) or free in the cytoso

Endoplasmic Reticulum

Rough ER: a region of the endoplasmic reticulum that specializes in protein synthesis; “rough” because of the ribosomes attached to its surface

Smooth ER: a region of the endoplasmic reticulum specialized for lipid synthesis; “smooth” because it lacks attached ribosomes

Golgi Apparatus: an organelle that routes proteins and lipids to various parts of the eukaryotic cell from the ER and synthesizes certain cellular products, notably non-cellulose carbohydrates

Organelles of plant cells:

Central Vacuole a large membranous sac in a mature plant cell that helps to maintain cell shape and can be used to store nutrients and anti-herbivory chemicals

Organelles of animal cells:

Mitochondrion (mitochondria): an organelle with a double membrane that is the site of cellular respiration in eukaryotes and is also involved in regulated cell death; capable of autonomous replication

Crista: folds in the inner membrane of the mitochondria

Cytoplasm: the contents of the cell enclosed by the membrane; excluding the nucleus

Nucleus: organelle in that contains genetic information, stored as DNA, organized as chromatin and chromosome

Nucleolus: a region of the nucleus that specializes in rRNA genes, ribosomal proteins, and ribosomal subunit assembly

Cell components of plant cells

Plasmodesmata

Cell wall: a fairly rigid polysaccharide; supportive and protective layer that lies outside of the plasma membrane of all plants

Components used for structure and motility

Intermediate filaments:fibers that stabilize cell structure—for example, maintaining the position of the nucleus and other organelles—composed of helical subunits of fibrous proteins

Microtubules:cylinders made of tubulin that function in motility (e.g.: flagella and cilia), support of cell shape, or transport of chromosomes and vesicles

Microfilaments: two actin polymers that function in cell shape, muscle action with myosin, cytoplasmic streaming, cell division and motility, and anchoring proteins in the plasma membrane

Cilium: a hair-like structure found in some eukaryotes that uses a rowing motion to propel the organism or to move fluid over cells

Flagellum: a long cellular extension that lashes and enables that cell to move (structure differently than prokaryotic flagella

Extracellular matrix: functions in the support and protection of the cell, as well as communication and association

Chemical Evolution Hypothesis

Synthesis of Organic Compounds

Sequences of Events proposed:

1. Abiotic synthesis of small organic molecules ( AA and nitrogenous bases)
2. Small molecules into macromolecules (proteins and nucleic acids)
3. Protocells packaging
4.The origin of self-replicating molecule that eventually made inheritance possible

Protocells: These are droplets with membranes that maintained an internal chem different from that of their surroundings

Mutations

Types:

Frameshift: a mutation that alters the reading frame of the mRNA molecule

Base pair substitutions the replacing of one base pair with another in DNA

Silent: a mutation in DNA that does not alter the amino acid sequence of the polypeptide chain

Nonsense: a mutation in DNA that results in the early termination of translation

Missense: a mutation in DNA that results in the replacement of one amino acid by anothe

Point: a change in just one nucleotide in the coding strand of DNA

Mutagen: a physical or chemical agent such as X rays, ultraviolet radiation, and carcinogens (e.g.:benzene), that causes mutations in DNA

Protein Traffic

An amino acid code tells the protein where to go

To the organelles

protein goes to...

Mitochondria

Peroxisomes

Chloroplast

Nucleus

Endomembrane system

mRNA attaches to ER

protein made in the ER is transported by microubules through vescicles

Golgi bodies add chemical tabs

Vesicles take it to the...

The rough ER

Plasma membrane

Lysosmes

Glycoprotein

Secretory pathway – path taken by a protein in a cell on synthesis to modification and then release out of the cell (secretion)

PCR: Polyermerase Chain Reaction

Components

DNA

Reaction buffer

DNA Polymerase

dNTP

DNA primers

Cycles

Lag
Exponential
Saturation

3 Steps:

1.Denature: Heat DNA to seperate strands

2. Annealing: primers anneal or attach to template DNA

3. Elongation: Taq polymerase extends copy

Central Dogma of Biology: Genetic
information flow can be divided into
three stages

Replication: DNA is duplicated

Proteins/Function

Helicase: Unwinds parental double helix at replication forks

Single-Stranded Binding Protein:
Binds to and stabilizes single-stranded
DNA until it can be used as a template

Topoisomerase: Relieves "overwinding"
strain ahead of the replication forks by breaking,
swiveling, and rejoining DNA strands

Primase: Synthesizes an RNA
primer at 5' end of the leading
and each of the Okazaki fragments
of lagging strand

DNA pol III: Synthesizes new DNA
by covalently adding nucleotides to
the 3' end of a pre-existing DNA
strand or RNA primer

DNA pol I: Removes RNA
nucleotides of primer from 5' end
and replaces them with DNA
nucleotides

DNA ligase: Joins 3' end of DNA
that replaces primer to rest of
leading strand and joins Okazakii
fragments of lagging strand

Structures

Origin of Replication: the point in the DNA at which replication begins; characterized by a particular sequence of nucleotides (the ORI sequence) containing a large number of A-T bonds

Strands:

Leading: synthesized continuously that is compliments DNA

Lagging: complementary strand that is put together in fragments; synthesized away from the replication fork

Okazaki fragments: a small segment of DNA
formed on the lagging strand using and RNA
primer

Replication fork: Separation of the two stands of DNA

Replication bubble: gap in between the separated DNA

Differences between prokaryotes and eukaryotes

Prokaryotes: have circular chromosomes with one ORI and one replications bubble

Eukaryotes: multiple origins of replication and multiple bubbles

Transcription: makes mRNA

Prokaryotes: process of transcription occurs
immediately

Initiation: Sigma Factor of RNA polymerase recognizes initiation sites on DNA called
promoters

Transcriptional units: DNA segments transcribed into 1 RNA molecules
bounded by initiation and termination sites

Operons are transcribed into a single NRNA called a polycistronic mRNA
containing multiple open reading frames than encodes amino acids

Eukaryotes: process occurs in the nucleus

RNA processing: modification of pre-mRNA before it leaves the nucleous

5'cap: Guanosine triphosphate that is added to the 5' end of the pre-mRNA; provides protection from enzymes that break down RNA

poly-A-tail: 100 to 300 adenines added to the 3' end

Uses ATP

Info to where this is added is at the poly A site

Cutting after AAUAAA by ribnuclease

RNA splicing: introns removed and exons joined together

Spiceosome: an RNA-protein that cuts out introns
and joins together exons

Exons: nucleotide sequences that cod for amino acids

Introns: non-coding nucleotide sequences in eukaryotic genes that are removed

Alternative splicing: variations in the splicin

What else is needed

Transcription Factors

Polymerases involved

RNA pol I: ribosomal RNA

RNA pol II: pre mRNA, snRNA, microRNA

RNA pol III: tRNA, 5S rRNA

After processing: formulation of mature mRNA

What is the same in prokaryotes/eukaryotes

Promoter: is a region of DNA that initiates transcription
of a particular gene; located upstream of DNA

Upstream: Location of the promoter starts at -1..-2..-3,etc.

Downstream: Direction of transcription; starts at 1...2...3, etc.

Translation: the making of protein, by forming a polypeptide
chain from mRNA

Components

mRNA messenger RNA

tRNA

Carries amino acid to translation machinery

Single Stranded, clover leaf shape

Anticodon: three bases on tRNA that recognize the codon on the mRNA

Ribosomes

Composed of protein and RNA

Prokaryotes

Subunits are 50s and 30s

Eukaryotes

Subunits are 60s and 40s

The binding sites for tRNA; large subunit

P site (Peptidyl-tRNA binding)

A site (Aminoacyl-tRNA binding site)

E site (exit site

The mRNA binding site on small subunit

Amino acids

Aminoacyl t-RNA synthetase: enzymes that catalyze the addition of an amino acid to a corresponding tRNA molecule

Peptidyl transferase: Formation of peptide bond

Initiation Factors: the ribosome attaches at the mRNA binding site. Attaches subunits

Elongation Factors: peptide bonds are joined together in a long sequence

Release Factors: the stop codon is read and the subunits break apart and the peptide chain is released

Polyribosome: several ribosomes simultaneously translating the same mRNA

Codons

Start Codon: a sequence of nucleotides in mRNA (AUG)
that provides the code for the first amino acid (Methionine) during translation

Stop: a sequence of nucleotides in mRNA (UAA, UAG
,UGA) which signals the termination of translation

Codon chart

Genetic Information

Genome: make up the total complement of genetic
infomation

DNA

Structure

Nucleotide bases

Puries

Guanine

Adenine

Pyrimidines

Thymine

Cytosine

Double helix

Backbone of made of alternating phosphates
and pentose sugar deoxyribose

Phosphodiester bonds connect 3'carbon of one
of one sugar 5' of adjacent sugar

Two strands are anti-parallel to one other to form double helix

Held together by hydrogen bonding between bases

Properties

Makes a full turn every 3.4 nm or every 10 layers of base pairs

Semi-conservative

Chargaff's Rules

DNA base compositions varies between species

For each species the percentages of A and T bases are roughly equal and so are G and C bases

Theories of the model of DNA

Semiconservative: two parent strands serve as templates for new complementary strands

Conservative: two parental strands act as template, the strands come back together and there is a daughter helix

Dispersive: Mixture of daughter strands and molecules of old and new DNA

Viral DNA- can program cells

Bacteriophages: viruses that infect bacteria

Phage T2: infects E. coli

Tested to see what was really causing the cells genetic make up to be altered

The phage DNA entered the cell but not the phage protein

Takes over the metabolic fuctioning of the cell

Proteins

Thermodynamics

1st Law: Energy is transferred and the total energy of a system and its surroundings are constant

2nd Law: Overall Entropy of the universe always increases

Entropy: the degree of randomness or disorder in a system

System- matter within a defined region of space

Closed: only heat can flow through, not matter

Open: both heat and matter can flow through

Surroundings: matter in the rest of the universe

Free Energy: the portion of a systems energy that can perform work

a measure of a systems instability, tendency to change to a more stable state

If reactants have more free energy than product, energy is released, and delta G is negative

Spontaneous

If products have have more free energy than the reactants, energy is required for the reaction, and the delta G is positive

Non spontaneous

Other types of energy

Kinetic: associated with motion of molecules

Potential: stored energy; due to position location or arrangement; potential energy in foods is chemical energy; Includes chemical energy stored in molecular structure

Metabolism

The totality of an organisms chemical reactions

Begins with a specific molecule and ends with a product

Each catalyzed by a specific enzyme

Catabolic Pathway

Pathways release energy by breaking down complex molecules into simpler compounds

Cellular respiration

REDOX reactions

Aerobic respiration

Most efficient catabolic pathway, where oxygen is consumed as a reactant along with organic fuel

Subtopic

Some ATP is made by direct transfer of a phosphate group from an organic substrate to ADP by an enzyme

Oxidative Phosphorylation

Powered by the redox reactions of the electron transport chain

Step 1: Glycolysis (in the cytoplasm)

Energy investment phase

a) Enzyme HEXOKINASE transfers a phosphate group from ATP to GLUCOSE making it more chemically reactive. We yield GLUCOSE 6-PHOSPHATE

1 ATP used

b) GLUCOSE 6-PHOSPHATE is converted to FRUCTOSE 6-PHOSPHATE by the enzyme PHOSPHOGLUCOISOMERASE

c) PHOSPHOFRUCTOKINASE transfers a phosphate group from another ATP to the opposite end of FRUCTOSE 6- PHOSPHATE yielding FRUCTOSE 1,6- Bisphosphate

1 ATP used

d) ALDOASE cleaves the sugar FRUCTOSE 1,6- Bisphosphate into two different three carbon sugars G3P and DHAP

e) G3P and DHAP convert into each other and now, 2 G3P are used in the next step as fast as it forms

Energy Payoff Phase

f) two things happen. Each of the 2 G3P's are oxidized by the transfer of electron to 1 NAD+ with the help of the enzyme TRIOSEPHOPHATEDEHYGROGENASE, forming 2 NADH's. The energy from this exergonic reaction allows a phosphate group to be attached to the oxidized substrate, making two high energy products called 1,3-BISPHOSPHOGLYCERATE

2 NADH's formed

g) The phosphate group in 1,3 BISPHOSPHOGLYCERATE is transferred to ADP in an exergonic reaction. The products yielded are 2 ATP and 2 3-PHOSPHOGLYCERATE. The carbonyl group of G3P has been oxidized.

2 ATP formed

h) after two more steps occur, The phosphate group is transferred from 2 PEP to 2 ADP, yielding 2 ATP and 2 PYRUVATE with the help of PYRUVATE KINASE

2 ATP formed

So in total we gained a net of 2 ATP, 2 NADH, and 2 Pyruvate

Step 2: Pyruvate Oxidation (In between the cytoplasm and the outer mitochondrial membrane)

a) 2 Pyruvates carboxyl groups are already somewhat oxidized, carrying a little chemical energy, and now fully oxidized giving off 2 CO2 molecules

2 CO2 released

b) Each molecule has two carbon fragments remaining. Each are oxidized and the electrons are transferred to 2 NAD+, storing energy to form 2 NADH

2 NADH released

c) Coenzyme A (CoA) a sulfur containing compound, is attached via its sulfur atom to the two carbon intermediate, forming Acetyl CoA. Since we start with 2 two carbon intermediates, 2 CoA's attach and we yield 2 Acetyl CoA's

2 Acetyl CoA's formed

So in total, 2 NADH were formed after pyruvate oxidation

Step 3: Citric Acid Cycle (Krebs Cycle); (occurs once fore each of the two Acetyl CoA so everything that is yielded in one cycle is doubled

a) Acetyl COA adds its two-carbon acetyl group to oxaloacetase, producing citrate

b) citrate is converted to its isomer, isocitrate, by the removal of one water molecule and the addition of another

c) Isocitrate oxidized reducing NAD+ to NADH. Then the resulting compound looses a CO2 molecule

Total of 2 NADH formed after each acetyl CoA undergoes cycle

d) another CO2 lost and he resulting compound is oxidized reducing NAD+ to NADH. The remaining molecule is then attatched to CoA

Total of 2 NADH formed after each acetyl CoA underges cycle

e) CoA displaced by a phosphate group, which is transferred to GDP, forming GTP, which can be used to generate ATP

Total of 2 ATP formed after each acetyl CoA undergoes cycle

f) Two hydrogens are transferred to FAD, forming FADH2 and oxidizing succinate, molecule formed after previous step

Total of 2 FADH2 formed after each acetyl CoA undergoes cycle

g)addition of water molecule rearranges bonds in the substrate

h) substrate is oxidized, reducing NAD+ to NADH and regenerating the molecule that began the process by interacting with Acetyl CoA

Total of 2 NADH formed after each acetyl CoA undergoes cycle

So in total we gained 6 NADH, 2 ATP, and 2 FADH2 after citric acid cycle

Step 4: Electron Transport Chain and Chemiosmosis (Both make up oxidative phophorylation)

a) the NADH and FADH2 formed in glycolysis, pyruvate oxidation, and the citric acid cycle are electron carriers and shuttle these high electrons into an electron transport chain built into the inner mitochondrial membrane

b) NADH carries and drops the electrons off at protein complex 1.

c) as complex 1 is about to shuttle the electrons to a mobile carrier Q, it pumps out protons from the matrix to the inner membrane space.

d) FADH2 deposits its electrons via complex 2, which is the only one not along the membrane, so fewer protons are pumped

e) electrons are shuttles to complex 3, then shuttle 3 shuttles them to mobile carrier c, pumping protons out of the matrix

f) electrons are shuttles from mobile carrier C to complex 4, the electrons are given to O2 which reacts with hydrogen ions, from the aqueous solution, forming water

g) the protons that were pumped out flow back down their gradient via ATP synthase which harnesses the proton motive force to phosphorylate, ADP, forming ATP

the process of H+ through ATP synthase uses the exergonic flow of H+ to drive the phosphoryation of ADP. Thus energy stored in an H+ gradient across a membrane couples the redox reactions of the ETC to ATP synthesis

Anaerobic respiration

Fermentation

Lactic Acid

a) Glycolysis resulting in 2 Pyruvate

b) 2 pyruvate is reduced directly by 2 NADH to form 2 lactate as an end product, regenerating 2 NAD+

Human muscle cells make ATP by Lactic Acid fermentation when oxygen is scarce, occurs in strenuous excercise, when sugar catabolism for ATP production outpaces the muscles supply of oxygen from the blood

Alcohol

a) Glycolysis resulting in 2 Pyruvate

c) Acetylaldehyde is reduced by NADH to ethanol, regenerating the the supply of NAD+ needed to continue glycolysis

Partial degradation of sugars or other organic fuels that occurs without the use of oxygen

Anaerobes

Faculative: can make enough ATP to survive using either fermentation or respiration

Obligate: Carry out only fermentation. These organisms can't survive in the presence of oxygen

Oxidation: Loose electrons

Oxidizing agent oxidizes the reducing agent by removing its electron

Reduction: Gaining electrons

Reducing agent reduces the oxidizing agent which accepts the electron

Exergonic reaction proceeds with the net release of free energy

Chemical mixture looses free energy, G decreases, so delta G is negative

Anabolic Pathway

Pathways that consume energy to build larger, complicated molecules from simpler ones

Biosynthetic pathways

Polymerization

Photosynthesis

Chloroplasts capture light energy and converts it to chemical energy, stored in sugar and other molecules

Chloroplasts found in cells of mesophyll inside leaves

made up of double membrane called stroma and sacs called thylakoids, which may be stacked as grana

Photosystems

Photosystems are areas of the plant cell populated in the thykaloid membrane that cooperate in light reactions, consisting of light-harvesting complex, reaction center complex, primary electron accepter, and pigment molecules

Photosystem 2

has a reaction center chlorophyll a called P680 because light is best absorbed by a wavelength of 680 nm (red zone)

comes before photosystem 1

Photosystem 1

has a reaction center chlorophyll a called P700 because light is best absorbed by a wavelength of 700 nm (far red zone)

Cyclic electron flow

Unlike linear electron flow, electrons cycle back from ferredoxin to the cytochrome complex, then to a P700 chlorophyll in the photosystem complex via plastocyanin molecule

no NADPH formed or oxygen released

As cycle repeats, ATP is generated

usually occurs in plants containing a single photosystem

light is absorbed by light harvesting complex in photosystems, consisting of chlorophyll a, the main photosynthetic pigment in plants, and chlorophyll b in algae

primary electron acceptor can accept electrons and become reduced

Linear electron flow

ATP and NADPH and synthesized by energizing both photosystems

Step 1: Photon of light strikes pigment molecule in light harvesting complex in photosystem 2

Step 2: Electron transferred from P680 to primary electron acceptor, resulting in P680+

Step 3: enzyme catalyzes splitting of water, electrons are supplied to P680+, H+ is released to thylakoid space, oxygen atoms combine and generate oxygen gas

Step 4: photo-excited electrons are passed from the primary electron acceptor of photosystem 2 to photosystem 1 via the electron transport chain with protein plastocyanin (cytochrome complex), each carrying out redox reactions, releasing ATP

ATP used to pump protons into thylakoid space, contributing to a proton gradient across thylakoid membrane

Step 5: Potential energy in proton gradient is used to make ATP through chemiosmosis

Step 6: Light energy excites electron of P700 pair of chlorophyll a molecules in photosystem 1, electron transfers to primary electron acceptor in photosystem 1, making P700+

Step 7: photo-excited electrons passed in redox reactions from primary electron acceptor of photosystem 1 to a second electron transport chain through protein ferredoxin (no ATP produced)

Step 8: enzyme NADP+ reductase catalyzes transfer of electrons from ferredoxin to NADP+, two electrons are required for reduction to NADPH, NADPH is released

Carbon dioxide enters stomata

Stage 1: Light reactions

water absorbed by roots

chloroplast splits hydrogen dioxide (water) into hydrogen and oxygen

hydrogen becomes a source of protons and electrons

Oxygen gas is released into the biosphere

light absorbed by chlorophyll

electrons from water transferred to NADP+

light reaction makes NADP+ become NADPH with added electron along with hydrogen from water

NADPH acts as reducing power

ATP generated by chemiosmosis through addition of phosphate to ADP (phosphorylation)

ATP provides energy to cells used in Calvin cycle

Stage 2: Calvin cycle

carbon is reduced using NADPH and ATP from light reactions to make carbohydrates

Step 1: Carbon fixation

Each carbon dioxide molecule is added to a 5 carbon sugar using rubisco

6 carbon product splits in half, forming 2 molecules of 3-phosphoglycerate

Step 2: Reduction

Each 3-phosphoglycerate receives an additional phosphate group

a pair of electrons from NADPH and a phosphate group is lost, generating glyceraldehyde 3-phosphate. (G3P)

Note: 3 CO2=6G3P formed

One molecule of G3P exits cycle to be used by plant cell, other 5 are recycled to regenerate 3 molecules of RuBP

Step 3: Regeneration of CO2 accepter

5 G3P molecules rearranged into 3 molecules of RuBP using 3 ATP

9 ATP and 6 NADPH used to synthesize 1 G3P

G3P that exited cell cycle becomes starting material for other metabolic pathways

Photorespiration

when stomata is closed, 3 carbon compound C3 plants produce produce less sugar, because of lack of CO2

Rubisco has ability to bind O2 in place of CO2 in the Calvin cycle

product splits and two carbon compound leaves chloroplast

peroxisomes and mitochondria within plant cell rearrange and split, releasing CO2

C4 plants

Bundle-sheath cells

tightly packed sheaths around veins of leaves

Mesophyll cells

more loosely packed than bundle-sheath cells

Calvin cycle of C4 plants

Step 1: in mesophyll cells, enzyme PEP carboxylase adds CO2 to PEP, generating 4 carbon compound

Step 2: Four carbon compound moves to bundle-sheath cell via plasmodesmata

Step 3: CO2 is released into the bundle-sheath cell, and enters the Calvin cycle

ATP is used to convert pyruvate to PEP, which allows intake of additional CO2

C4 plants have no photosystem 2

Autotrophs

sustainable without eating other livings, use sunlight and minerals in soil for nutrition, (plants)

Heterotrophs

feed off of other livings things for nutrition (animals and decomposers)

Endergonic reaction is one that absorbs free energy from its surroundings

This reaction stores free energy in molecules, G increases, so delta G is positive

Work

Chemical: pushing of endergonic reactions that don't occur spontaneously

Synthesis of polymers from monomers

Transport Work: pumping of substances across membranes against direction of spontaneous movement

ATP phosphorylates transport proteins, causing a shape change that allows transport of solutes

Mechanical Work: the beating of the cilia, contraction of muscles, and movement of chromosomes during cellular reproduction

ATP binds non-covalently to motor proteins and then is hydrolyzed, causing a shape change that walks the motor protein forward

Energy coupling is the way the cells manage their energy resources to do these kinds of work

Energy coupling using ATP hydrolysis

Step 1: Endergonic reaction delta G is positive, reaction is not spontaneous

Step 2: Exergonic Reaction delta G is negative, reaction is spontaneous

Coupled reactions: Overall delta G is negative together, reactions are spontaeous

How ATP drives chemical work: Energy coupling using ATP Hydrolysis

a) Glutamine synthesis from glutamic acid by itself is endergonic, non spontaneous

b) ATP phosphorylates glutamic acid, makes it less stable, more free energy and ammonia later displaces the phosphate group from glutamine

c) delta G for glutamic acid conversion to glutamine is +delta G plus - delta G for ATP hydrolysis gives a - free change for the overall reaction. An exergonic process coupled with an endergonic reaction made the overall process spontaneous and exergonic

Enzymes

A macromolecule then acts as a catalyst, a chemical agent that speeds up a reaction without being consumed by the reaction

Activation energy is the initial investment of energy for starting a reaction- the energy required to contort the reactant molecules so the bonds can break.

Catalysts will lower the activation energy of a process and delta G will be unaffected by catalyst

Substrate: the reactant and enzyme acts on

The enzyme has a region called the active sit and will bind to its substrate here, forming the enzyme-substrate complex

Induced Fit: tightening of the binding after initial contact. Brings chemical groups of the active site into positions that enhance their ability to catalyze the chemical reaction

Lock and Key

Substrate is held in active site by weak interactions like hydrogen and ionic bonds

The active site lowers activation energy and R groups of a few of the amino acids that make up the active site catalyze the reaction

Substrate is converted to the product or products of the reaction due to the catalytic action of the enzyme

enzyme can stretch substrates toward transitional state forms, doing this breaks critical chemical bonds and reduces the amount of free energy to be absorbed

Enzyme can provide a microenvironment. An enzyme with amino acids with acidic R groups will provide an environment of low. acidic pH. In this case, an amino acid may facilitate the amount of H+ transfer to substrate as key step in catalyzing reaction

If there are two or more reactants, the active site provides a template on which substrates can come together in the proper orientation for a reaction to happen

Amino acids in active sites directly participate in chemical reactions like brief covalent bonding between substrate and the side chain of said amino acids in the enzyme.

The more substrate molecules, the more frequently they access the active sites of an enzyme molecule

Temperature and pH are important in enzyme activity

Rate of reactions increase with temperature because substrates collide more with active sites.

However, after a certain point, a super high temp will drop the speed sharply of the reaction. It disrupts the bonding and other weak interactions tht stabilize the active shpe of the enzyme

Humans and bacteria have enzymes that each have a specific optimal temperature and pH.

Cofactors: Enzymes require non protein helpers for catalytic activity. These are bound tightly to the enzyme as permanent residents, or bind loosely and reversibly along with the substrate

Enzyme inhibitors

Competitive inhibitor: reduce productivity of enzymes by blocking substrates from entering active sites.

Can be overcome by oversaturation of substrates

Non-competitive inhibitors: do not directly compete with the substrate to bind to the enzyme at the active site. They impede enzymatic reactions by binding to another part of the enzyme, causing enzyme to change shape and the active site to become less effective at catalyzing the reaction

Regulation of enzyme activity helping to control metabolism

Enzymes known to be allosterically regulated are constructed from two or more subunits, each composed of a polypeptide chain with its own active site. Oscillates between two different shapes, one active and inactive

Allosteric regulation: any case in which a protein's function at one site is affected by the binding of a regulatory molecule to a separate site.

Acivator

Stabilizes the shape that has functional active sites

ADP functions as an activator. If ATP production lags behind its use, ADP accumulates and activates the enzymes that speed up catabolism, producing more ATP

Inhibitor

Stabilizes the inactive form of the enzyme

ATP binds to several catabolic enzymes allosterically, lowering their affinity for substrate and inhibiting their activity. IF ATP exceeds demand, then catabolism slows down as ATP molecules accumulate and bind to the same enzymes to inhibit activity.

Cooperativity

Another type of allosteric activation, substrate binds to one active site in a multisubunit enzyme and triggers a shape change in all the subunits, increasing catalytic activity at other active sites

Amplifies the response of enzyme to substrates: the substrate primes an enzyme to act on additional substrates more readily

Considered allosteric regulation due to the substrates binding affecting the catalysis in another active site

Feedback Inhibition

A metabolic pathway is halted by the inhibitory binding of its end product to an enzyme that acts early in the pathway

Enzymes

are Catalysts
speed up rxn time
lowers activation energy

CDK cyclin
Functions in cell cycle regulation

Beta Galactosidase
breaks down lactose to glucose and galactose

Kinases
adds a phosphate group

phosphodiesterase
converts cAMP to AMP

phosphatase
removes phosphate groups

Adenylyl cyclase
converts ATP to cAMP

BRCA1, BRCA2
tumor supressor
gene, helps repair
DNA and kills cells
that cannot be
repaired

p53
functions in cell cycle regulation
tumor supressor gene

Ras
mutation in this gene leads to formation of oncogene

Cyclins
structurally and functionally related proteins

aquaporin
integral membrane protein
channel for water to more
rapidly diffuse across the
membrane

Hexokinase
glucose to G6P

Phosphofructokinase
F6P to F1,6Bis

ATP synthase
uses chemiosmosis to
generate ATP

RuBisCo
combines RuBP and CO2
to make intermediate
6 carbon molecule

enzyme binds to
substrate
is bound by multiple
weak attractions

active site

where the enzyme
binds to on the
substrate
is a 3D cleft/
crevice formed
by folding of protein
and amino acids

lock and key

enzyme has very specific
fit to the active site

induced fit

does a "dance"
with the enzyme
to induce a
better fit

feedback inhibition

when the product of the
transduction pathway
is in abundance and
no longer needs to be
produced

the product will
bind to the active
site

this inhibits further
production of the
end product

DNA packaging

DNA

Histone core
(H2A,H2B, H3, H4)

Nucleosome

Tight helical fiber

Looped domains

Metaphase chromosome

Regulation of Gene expression

Eukaryotes

Control elements

Distal (specific)

High level expression

Far from promoter
May be upstream or downstream
may even be in intron
ex: enhancer., amount of activator
protein is important for functionality

Activators bind to enhancer sequence

This signals for DNA bending protein to come in

Group of mediator proteins and
general TF comes in

RNA pol II comes in and from transcription
complex, begins transcription

Proximal (general)

Basal level expression

Very close to promoter, always "on"

can never turn expression
"off", just basal level (which
is basically off)

Not all genes expressed in
every cell, compacted

Heterochormatin

Genes tightly packed,
do not get expressed
(this silences genes)

Chromatin

Gets modified to DNA (gene)
is available for transcription

Transcription, gets spliced to mRNA

Cap and tail added, exported to cytoplasm

Gets translated
turned into polypeptide

is processed and turned into a functioning protein

has cellular function

Euchromatin

Less compacted
genes expressed

Prokaryotes

Operons- controlled with multiple start/ stop codons

Positive regulation

Activator binds to the
operator and is turned on

no activator- no translation

Negative regulation

the repression binds to the operator
to keep the enhancers from binding
and activating the sequence

no repressor- translation occurs

Examples

Trp

is active in absence
or tryptophan

repressor is made inactive

trp is synthesized
when there is none
available

trp present- binds to inactive
repressor, making it active
and inhibiting production of trp

Lac

is active in the presence
of lactose

CAP and cAMP must be
present for operon to
function

if glucose is present
the lac I repressor will
bind to CAP thereby
inhibiting gene Y,Z,A
production

Lac absent, repressor
bound to active site

Lac present, repressor
bound to lac and genes
are expressed

Subtopic

Pumps

Electrogenic

Na/ K pump

Salty banana

resting potential
-70 mV

stimulus comes and
stimulates the membrane
and it reaches threshhold
-55mV

Depolarization
sodium gates open
and sodium floods the
cell

Action potential
+40 mV
ligand gated sodium
channels close promptly
upon reaching +40mV

Repolarization
potassium channels open and
K floods out of the cell, making
the cell more negative

Undershoot/ refractory period
the cell potential reaches a very
negative point and the K pumps
lag to close

sodium potassium pump activates
it pumps 2 Na+ out and 3 K+ in

cell membrane returns
to resting state
to

energy coupled

sucrose/ proton
cotransporter

H+ pump

aka proton pump

used in chemiosmosis

helps generate ATP
by creating chemical
gradient

used in photosynthesis
and glycolysis

Reproducing

Meiosos (germ cells)

first round of division
crossing over occurs
homologs are separated

homologous chromosomes are
separated, sister chromatids are
still parired up to this point

prophase II

Metaphase II

ANAphase II
sister chromatids are separated

Telophase II

Cytokinesis II

these are the same steps as
mitosis but there is crossing over
and the 4 resulting daughter cells are
haploids instead of diploids

only has one half enough DNA
to make a person

Interphase

both cycles go through this
about 90% of cell cycle is
spent here

G1

organelles begin to duplicate

S

synthesis- chromosomes
condense from chromatids
and form sister chromatids
these are connected at
the centromere

G2

organelles finish duplication

must pass CDK checkpoint

begins reproductive phase

Mitosos (somatic cells)

Prophase- nucleoli disappear

Metaphase-chromosomes align along plate

Anaphase- telomeres attach to the
chromosomes

Telophase- chromosomes move to
opposite sides of cell and duplicated
organelles do too

Cytokinesis- the chromosomes and
organelles are enclosed in a new cell
membrane and the cell divides.

2 diploid daughter cells are
produced

Only accounts for about
10% of reproductive cycle

Cancer

uncontrolled cell
growth

the cell is mutated in
some way which causes
this growth

loss of density dependent
and anchorage dependent
growth inhibition

able to invade and
disrupt nearby
and distant tissue

protoncogenes (growth
factors) that are
mutated to oncogenes
are cancer causing
m

Tonicity

Hypertonic

cell is more concentrated
than surrounding solution

Animals

Flaccid

Plants

plasmolyzed

isotonic

cell and solution is
at equilibrium

Plants

flaccid

Animals

Turgid

hypotonic

cell has less concentrated
inside than the surrounding solution

plants

Turgid

Animals

lysed

THE MOST ABUNDANT ELEMENTS FOUND IN ORGANISMS ARE H, C, N, O, Na, Mg, P, S, Cl

POLAR

Two atoms with DIFFERENT electronegativity values share electrons unequally -POLAR COVALENT

EXAMPLES

AMMONIA NH3

WATER H20

NONPOLAR

Two atoms with SIMILAR electronegativity values share electrons equally -NONPOLAR COVALENT

INTRAMOLECULAR BOND

ATOMS HAVE NO CHARGE

Instead of a bond between just two atoms, a metallic bond is a sharing of electrons between many atoms of a metal element

Metallic bonds often have very low electronegativity differences or none at all.

The rule is that when the electronegativity difference is greater than 2.0, the bond is considered ionic

Subtopic

IONIC COMPOUNDS ARE OFTEN SALTS/CRYSTALS

ATOMS HAVE FULL CHARGE

IONS

EXAMPLE

Na and Cl

Na+ and Cl-

CATION IS POSITIVELY

ANION IS NEGATIVELY

IN THE CELLULAR MEMBRANE YOU CAN SEE THAT IT IS MADE UP OF PHOSPHOLIPIDS THAT HAVE HYDROPHOBIC TAILS

EVAPORATIVE COOLING

OCCOURS BECAUSE THE HOTTEST MOLECULES, THOSE WITH THE GREATEST KINETIC ENERGY, ARE THE MOST LIKELY TO LEAVE AS A GAS

CAN POLAR MOLECULES DISSOLVE IN WATER???

MOLECULES WITH POLAR BONDS THAT FORM HYDROGEN BONDS WITH WATER CAN DISSOLVE IN WATER AND ARE TERMED HYDROPHILIC

CLINGS TO POLAR MOLECULES

ADHESION

THE CLINGING OF ONE SUBSTANCE TO ANOTHER, ADHESION OF WATER BY HYDROGEN BONDS TOO THE MOLECULES OF CELL WALLS HELP COUNTER THE DOWNWARD PULL OF GRAVITY

COHESIION

HYDROGEN BONDS THAT HOLD THE SUBSTANCES TOGETHER, IT CONTRIBUTES TO THE TRANSPORT OF NUTRIENTS AND WATER AGAINST GRAVITY IN PLANTS

HIGH SPECIFIC HEAT

IS DEFINED AS THE AMOUNT OF HEAT MUST BE ABSORBED OR LOST FOR 1 G OF THAT SUBSTANCE T CHANG ITS TEMPERATURE BY 1 DEGREE CELCIUS

THE ABILITY OF WATER TO STABILIZE TEMPERATURE STEMS FROM ITS RELATIVELY HIGH SPECIFIC HEAT

HGH HEAT OF VAPORIZATION

HIGH HUMIDITY ON A HOT DAY PREVENTS EVAPORATION DUE TO MOISTURE IN AIR - CAUSES DISCOMFORT

IS THE QUANTITY OF HEAT A LIQUID MUST ABSORB FOR I G OF IT TO BE CONVERTED FROM THE LIQUID TO THE GASEOUS STATE

DENSER AS A LIQUID THAN A SOLID

LIQUIDS- EXPAND WHEN HEATED, CONTRACT WHEN COOLED

ANDCEPTION WATER BETWEEN 0-4 DEGREES CELCIUS

CONTRACTS UNTIL 4 DEGREES CELCIUS

MDENSE AT 4 DEGREES CELCIUS

ANDXPANDS FROM 4 TO 0 DEGREES CELCIUS

THE SOLVENT OF LIFE

SOLVENT

DISSOLVING AGENT

SOLUTE

THE SUBSTANCE BEING DISSOLVED

POLAR COVALENT

IN SOME CASE SUBSTANCES CAN BE HYDROPHILIC WITHOUT ACTUALLY DISSOLVING

SUBSTANCES THAT ARE NONIONIC OR NONPOLAR REPPEL WATER

the signal is recieved by the GPCR on the exterior of the
cell membrane

the GPCR experiences a conformational change because
of the binding of the ligand

the shape change causes the g protein to move away
from the GPCR and ATP binds to the separated
subunit and activates it

the activated subunit signals for the target protein
to come bind to it, in this case is Adenylyl cyclase

the AC turns ATP to cAMP which kicks off the
phosphorylation cascade

kinases add phosphates to kinases, thereby
activating and deactivating kinases

this phosphorylation cascade amplifies the
Original signal that was sent

once the cascade reaches a certain point
it will do what the signal sent for

in this case of the epinephrine transduction
pathway, the kinase will reach a certain
molecule that when activated will begin
to cleave off glucose from glycogen

the glucose will either stay in the cell and
serve as fuel for that cell or be
exported to the cytoplasm to be taken

IS A SUBSTANCE THAT MINIMIZES CHANGES IN THE CONCENTRATION OF H+ AND OH- IN A SOLUTION

PART OF THE HYDROCARBON TAIL OF A FATTY ACID MILECULE

CARBON SKELETON VARIATIONS

LENGTH

ETHANE

PROPANE

BRANCHING

BUTANE

2METHYLPROPANE

double bonds

1-Butene

two Butene

rings

benzene

cyclohexane

COMPOUNDS THAT HAVE THE SAME NUMBERS OF ATOMS OF THE SAME ELEMENTS BUT DIFFERENT STRUCTURES AND HENCE DIFFERENT PROPERTIES

STRUCTURAL

HAVE DIFFERENT COVALENT ARRANGMENTS OF THEIR ATOMS

RESULTS

MILLERD IDENTIFIED A VARIETY ORGANIC MOLECULES THAT ARE COMMON IN ORGANISMS. tHESE INCLUDED SIMPLE COMPOUNDS, SUCH AS FORMALDEHYDE (CH2O) AND HYDROGEN CYANIDE, AND MORE COMPLEX MOLECULES SUCH AS AMINO ACIDS

GEOMETRIC

SAME COVALENT ARRANGMENTS BUT DIFFER IN SPATIAL ARRANGMENTS

CIS ISOMER

THETWO Xs are on the same side

TRANS ISOMER

the two Xs are on opposite sides

ENANTIOMERS

l isomer d isomer, same in every aspect but reflected

toimportant in the pharmaceutical industry

SOURCE OF ENERGY

ATP OR ADENOSINE TRIPHOSPHATE IT CONSISTS OF AN ORGANIC MOLECULE CALLED ADENOSINE ATTACHED TO A STRING OF THREE PHOSPHATE GROUPS

such as estradiol and testerone

hydroxyl group

IS POLAR DUE TO ELECTRONEGATIVE OXYGEN FORMS HYDROGEN BONDS WITH WATER , HELPING DISSOLVE COMPOUNDS SUCH AS SUGARS

carbonyl group

SUGAR WITH KETONE GROUPS ARE CALLED KETOSES; THOSE WITH ALDEHYDES ARE CALLED ALDOSES

carboxyl group

ACTS AS AN ACID CAN DONATE H+ BECAUSE THE COVALENT BOND BETWEEN OXYGEN AND HYDROGEN IS SO POLAR

amino group

ACTS AS A BASE; CAN PICK UP AN H+ FROM THE SURROUNDING SOLUTION (WATER, IN LIVING ORGANISM)

sulfhydryl group

TWO SH GROUPS CAN REACT FORMING A CROSS-LINK THAT HELPS STABILIZE PROTEIN STRUCTURE. HAIR PROTEIN MAINTAIN STRAIGHTNESS AND SO ON

phosphate group

CONTRIBUTES NEGATIVE CHARGE WHEN POSITIONED INSIDE A CHAIN OF PHOSPHATES, WHEN ATTACHED CONFERS ON A MOLECULE THE ABILITY TO REACT WITH WATER RELEASING WATER

methyl group

AFFECTS THE EXPRESION OF GENES WHEN ON DNA OR ON PROTEINS BOUND TO DNA, AFFECTS THE SHAPE AND THE FUNCTION OF MALE AND FEMALE SEX HORMONES

ORGANIC MOLECULES, A FIRST STEP IN THE ORIGIN OF LIFE MAY HAVE BEEN SYNTHESIZED ABIOTICALLY ON THE EARTH. ALTHOUGH NEW EVIDENCE INDICATES THAT THE EARLY EARTH'S ATMOSHPHERE WAS DIFFERENT FROM THE ATMOSPHERE

IS BIOLOGICALLY FUNCTIONAL MOLECULE MADE UP OF ONE OR MORE POLYPEPTIDES EACH FOLDED AND COILED INTO SPECIFIC THREE-DIMENSIONAL STRUCTURE

CATALYSTS

CHEMICAL AGENTS THAT SELECTIVELY SPEED UP CHEMICAL REACTIONS WITHOUT BEING CONSUMED IN THE REACTION

AMINO ACIDS

SET OF 20 AMINO ACIDS LINKED IN UNBRANCHED POLYMERS

BOND BETWEEN THEM IS CALLED A PEPTIDE BOND SO A POLYMER OF AMINO ACID IS CALLED A POLYPEPTIDE

POLYPEPTIDES

POLYMER OF AMINO ACID

DENATURATION

IF THE PH, SALT CONCENTRATION, TEMPERATURE, OR OTHER ASPECTS OF ITS ENVIRONMENT ARE ALTERED THE WEAK CHEMICAL BONDS AND INTERACTIONS WITHIN A PROTEIN MAY BE DESTROYED CAUSING IT TO UNRAVEL AND DENATURE

PROTEIN STRUCTURE

ALL AMINO ACIDS SHARE A COMMON STRUCTURE AND THAT IS THAT OF THE AMINO ACID

IS AN ORGANIC MOLECULE WITH BOTH AN AMINO GROUP AND CARBOXYL GROUP

ITS FOUR DIFFERENT PARTNERS

VARIABLE GROUP CALLED THE R GROUP

A HYDROGEN ATOM

A CARBOXYL GROUP

AMINO GROUP

FOUR LEVELS OF PROTEIN STRUCTURE

PRIMARY

LINEAR CHAIN OF AMINO ACIDS

ITS SEQUENCE OF AMINO ACIDS

SECONDARY

REGIONS STABILIZED BY HYDROGEN BONDS BEWTWEEN ATOMS OF THE POLYPEPTIDE BACKBONE

COILDE OR FOLDED IN PATTERNS THAT CONTRIBUTE TO THE SHAPE

RESULT OF HYDROGEN BONDS BETWEEN THE REPEATING CONSTITUENTS OF THE POLYPEPTIDE BACKBONE, THE OXYGEN

TERTIARY

THREE DIMENSIONAL SHAPE STABILIZED BY INTERACTIONS BETWEEN SIDE CHAINS

SubtopicVERALL SHAPE OF A POLYPEPTIDE RESULTING FROM INTERACTIONS BETWEEN THE SIDE CHAINS R GROUPS OF THE VARIOUS AMINO ACIDS

HYDROPHOBIC INTERACTION, AS A POLYPEPTIDE FOLDS INTOITS FUNCTIONAL SHAPE, AMINO ACIDS WITH HYDROPHOBIC NONPOLAR SIDE CHAINS USUALLY WND UP IN THE CLUSTERS AT THE CENTER/CORE OF THE PROTEIN

COVALENT BONDS CALLED DISULFIDE BRIDGES MAY FURTHER REINFORCE THE SHAPE OF A PROTEIN, FORM WHERE TWO CYSTEINE MONOMERS, WHICH HAVE SULFHYDRL GROUPS ON THEIR SIDE CHAINS

QUATERNARY

ASSOCIATION OF TWO OR MORE POLYPEPTIDES (SOME PROTEINS ONLY)

IS THE OVERALL PROTEIN STRUCTURE THAT RESULTS FROM THE AGGREGATION OF THESE POLYPEPTIDE SUBUNITS

EXAMPLE IS THAT OF COLLAGEN

DNA

DEOXYRIBONUCLEIC ACID

THE GENETIC MATERIAL THAT ORGANISM INHERIT FROM THEIR PARENTS

THE AMINO ACID SEQUENCE OF A POLYPEPTIDE IS PROGRAMMED BY A DISCRETE UNIT OF INHERITANCE KNOWN AS GENE

RNA

RIBONUCLEICO ACID

GENE EXPRESSION

DNA DIRECTS RNA SYNTHESIS AND THROUGH RNA CONTROLS PROTEIN SYNTHESIS

COMPONENTS OF NUCLEIC ACIDS

ARE MACROMELCULES THAT EXIST AS POLYMERS CALLED POLYNUCLEOTIDES

A NUCLEOTIDE IS COMPOSED OF THRREE PARTS

AND ONE THREE PHOSPHATE GROUP

A NITROGEN CONTAINING BASE

PYRIMIDINE

HE HAS A ONE SIX-MEMBERED RING OF CARBON AND NITROGEN ATOMS, CYTOSINE C, THYMINE, T AND URACIL U

PURINES

ARE LARGE WITH A SIX MEMBERED RING FUSED TO A FIVE MEMBERED RING, THEY ARE ADENIN A AND GUANINE G

A FIVE-CARBON PENTOSE SUGAR

DNA THE SUGAR IS DEOXYRIBOSE

IN RNA IT IS RIBOSE

consist of mainly of hydrocarbons

hydrophobic behavior is based on their molecular structure

they mix up poorly if at all with water

lipids are the one class of large biological molecules tht does not include true polymers, and they are not big enough to be considered macromelecules

CHEMICALLY MODIFIED CARBOHYDRATES

CARBOHYDRATES PARTICIPATE IN MOLECULAR TARGETING AND CELL-CELL RECOGNITION

CHITIN

POLYMER OF N ACETYL GLUCOSAMINE

AMINO SUGARS

GCOSAMINE, AND GALACTOSAMINE, AMINO GROUP INSTEAD OF A OH

SUGAR PHOSPHATE

FRUCTOSE1,6 BISPHATE

GLUCOSE 6 PHOSPHATE

STRUCTURE POLYSACCHARIDE

CHITIN

STR SIMILAR TO CELLULOSE

CAN USED AS SURGICAL THREAD

IS FOUND IN THE EXOSKELETON OF THE ARTROPODS

CELLULOSE

1-4 LINKAGE OF BETA GLUCOSE MONOMERS

ABOUT 80 CELLULOSE MOLECULES ASSOCIATE TO FROM A MICROFIBIL THE MAIN ARCHTURAL UNOT OF THE PLANT CELL WALL

A CELLULOSE MOLECULE IS AN UNBRANCHED B GLUCOSE POLYMER

DEXTRAN

IS A GROUP OF GLUCOSE POLYMERS MADE BY CERTAIN BACTERIA , ARE USED THERAPEUTICALLY AS PLASMA VOLUME EXPANDERAS AND ANTICOAGULANTS

STARCH

USED FOR ENERGY STORAGE IN PLANT CELLS

1-4 LINKAGE OF ALPHA GLUCOSE MONOMERS

GLYCOGEN

ANIMAL

BRANCHED

PLANT

UNBRANCHED

DSACCHARIDES

GLUCOSE AND FRUCTOSE

SUCROSE

CLUCOSE PLUS GLUCOSE

MALTOSE

SUGARS

ALDOSES

IN THE TAIL

KETOSES

IN THE MIDDLE

LINEAR AND RINGS FORMS

SUCROSE

BETA

ALPHA

CONDESTIONS (DEHYDRATION) REACTIONS

A SHORT POLYMER AND AN UNLINKED MONOMER DEHYDRATE AND H2O IS CREATED, REMOVING A WATER MOLECULE, FORMING A NEW BOND

ARE NOT POLYMERS

ARE LARGE MOLECULES ASSEMBLED FROM SMALLER MOLECULES BY DEHYDRATION REACTIONS

IS CONSTUCTED FROM TWO KINDS OF SMALLER MOLECULES GLYCEROL AND FATTY ACIDS

FATTY ACID

HAS A LONG CARBON SKELETON, USUALLY 16 OR 18 CARBON ATOMS IN LENGTH

GLYCEROL JOINED BY ESTER LINKAGE

RESULTS IN TRIACYGLYCEROL

UNSATURATED

HAS ONE OR MORE DOUBLE BONDS WITH ONE FEWER HYDROGEN ATOM ON EACH DOUBLE CARBON

NEARLY EVERY DOUBLE BOND IN NATURALLY OCCURING FATTY ACIDS IS A CIS DOUBLE BOND

AT ROOM TEMPERATURE THE MOLECULES OF AN UNSATURATED FAT SUCH AS OLIVE OIL CANNOT PACK TOGETHER CLOSELY ENOUGH TO SOLIDIFY BECAUSE OF THE KINKS IN SOME OF THEIR FATTY ACIDS

TRANS FAT

also called unsaturated fatty acids or trans fatty acids, are a type of unsaturated fat that occur in small amounts in nature, but became widely produced industrially from vegetable fats

CIS FATS

NATURALLY OCCURING DOUBLE BONDS

SATURATED

IF THERE ARE NO DOUBLE BONDS BETWEEN CARBON ATOMS COMPOSING THE CHAIN THEN AS MANY HYDROGEN ATOMS AS POSSIBLE ARE BONDED TO THE CARBON

AT ROOM TEMPERATURE THE MOLECULES OF SAT FAT SUCH AS THE FAT IN BUTTER ARE PACKED CLOSELY TOGETHER, FORMING A SOLID

STRUCTURAL FORMULA HAS NO DOUBLE BONDS

CONSISTS OF A HYDROPHILIC HEAD AND HYDROPHOBIC TAILS

THE THIRD HYDROXYL GROUP OF GLYCEROL IS JOINED TO A PHOSPHATE GROUP WHICH HAS A NEGATIVE CHARGE IN THE CELL

IS SIMILAR TO A FAT MOLECULE BUT HAS ONLY TWO FATTY ACIDS ATTACHED TO GLYCEROL RAHER THAN THREE

ARE LIPIDS CHARACTERIZED BY A CARBON SKEETON CONSISTING OF FOUR FUSED RINGS

DISTINGUISHED BY THE PARTICULAR CHEMICAL GROUPS ATTACHED TO ENSEMBLE OF RINGS