Categorii: Tot - enzyme - signaling - receptor - electron

realizată de Dyuti Krishnamurthy 2 ani în urmă

233

Biology Concept Map

The document outlines key biological processes, focusing on electron transport in photosynthesis and different types of cellular signaling. In photosynthesis, electrons are transferred between molecules, involving components like the electron transport chain, primary electron acceptor, and Photosystem I.

Biology Concept Map

Proteins (enzymes) are used to break down cell waste in lysosomes

glucose reacting with other molecules to form different types of sugars

Cannot occur without

plays a part in

Takes place in

Takes place in

releases

enters A site

translation ends

are moved from one tRNA to next tRNA

between

forms

As tRNA travels from A site to P site

Peptidyl transferase

Peptide bonds
Amino acids

Polypeptide chain formed

End codon is reached

Release factor

Complex breaks apart

tRNA (w/o amino acid)

Polypeptide chain

Both ribosomal units

attaches corresponding amino acid to

Aminoacyl tRNA synthetase

begins with

Elongation Begins

first tRNA starts in

part of

Initiation Complex

initiation complex complete

Process that creates

binds to

binds to

Contains

tRNA in P site moves to

here

next tRNA enters

Sequence

Sequences

Translation

Cytosol

Codons
Sequence of 3 Nucleotides

AUG

Begins Translation

UAA, UAG, UGA

Ends translation

small ribosomal subunit
tRNA carries anti codon

Start Codon (AUG)

Large Ribosomal subunit joins complex

P site

anti codon pairs with corresponding codon

E site (exit site)

tRNA in A site moves to

Transcription

terms

upstream
toward 5' end of DNA
toward 3' end of RNA
downstream
toward 5' end of RNA
toward 3' end of DNA

DNA- dependent RNA polymerase

in 5' to 3' direction
in 3' to 5' direction
DNA polymerase

stop codon

promoter

mRNA

ribosomes
pre-mRNA
introns

spliced out

snRNP's

exons

expressed

a 5' cap made of modified guanine

translation

stability

eukaryotes

comprised of nucleotides made of nitrogenous bases

Metabolism

Anabolism

building up of molecules
requires energy

Catabolism

breaking down of molecules
releases energy

Energy of Life

Chemical Energy

Thermodynamics

entropy always seeks to increase over time

Conservation of Energy

energy cannot be created/destroyed

Photolysis

Two Electrons

Electron Transport Chain
Primary Electron Acceptor
Photosystem I P700

ETC

2 NADH

cell releases signal molecule

Cell Communication

Physical Contact

Junctions
Desmosomes

Provides a connection between intermediate filaments

Somewhere between gap and tight!

Plasmodesmata

Chanel between cells

only found in plant cells

Tight

prevent fluid from moving across cells.

Gap

Open channel between cells

Allows free flow of ions and small molecules

takes place in the

Signaling

Signal Molecule/ ligand

Signal must be received by a receptor
Signal is non-polar hydrophobic

Intermembrane Receptor

1) steroid hormone passes through the plasma membrane.

2) hormone binds with receptor protein and activates it

3) hormone-receptor complex enters the nucleus and binds to specific genes.

bound protein acts as a transcription factor

4) stimulating the transcription of the gene into mRNA

5) mRNA is translated into a specific protein.

signal is polar/hydrophilic

Membrane Receptor

Tyrosine Kinase

Receptor tyrosine kinase proteins (inactive monomers) (2 of them)

each receptor has 3 tyrosines

1) 2 Signaling molecules bind to the 2 binding sites

the monomers combine to create a dimer

2) 6 ATP is used to add a Pi to each tyrosine

activating the tyrosine kinase dimer

2) Inactive relay proteins attach to the tyrosine dimer

relay proteins become activated

Triggers Cellular response

Ion Chanel

signal molecule attaches to the Ligand-gated ion receptor

channel opens

specific ions are allowed through the channel into the cytoplasm

Triggers Cellular response

When ligand leaves receptor, channel closes

G Protein coupled receptor

1) Ligand binds to extracellular receptor

receptor changes shape and activates G protein

Activated protein carries GTP molecule

2) activated G protein leaves the receptor, diffuses along the membrane, and then binds to an enzyme

enzyme changes shape and becomes activated

3) Enzyme takes ATP and makes cAMP(2nd messenger)

4) cAMP activates Protein Kinase A

Triggers cellular response

Long Distance Signaling/ Hormonal Signaling

Hormone travels through blood steam to reach target cell

Local Signaling

Paracrine Signaling
Synaptic Signaling
Nerve cell signaling

1) An action potential arrives, depolarizing the presynaptic membrane.

2) depolarization opens voltage-gated channels

Triggering an influx of Ca2+

3) elevated Ca2+ concentration causes synaptic vesicles to fuse with the presynaptic membrane

neurotransmitter is released into synaptic cleft

4) neurotransmitter binds to ligand-gated ion channels

Cellular Respiration

dependent on each other as the products of each of these reactions initiate the other reaction

three distinct processes

Citric Acid Cycle
step 1- Acetyl CoA adds its two carbon group to oxoloacetate which produces citrate

step 2- Citrate converts to Isocitrate, with the loss and gain of an H2O molecule

step 3- * Isocitrate is oxidized while NAD+ is reduced. a-Ketoplutarate is made

step 4- CO2 is released from a- ketoglutarate, which causes four-carbon molecules to be oxidized, then CoA is added, which makes it reactive, NADH+ & H+ is formed. CoA-SH is added, creating Succinyl CoA

step 5- A phosphate group is added to Succinyl CoA. GTP is released, which binds with ADP, that results in the formation of ATP. COA-SH is released, and Succinate is the end result.

step 6- Succinate is oxidized, FAD is reduced, FADH2 is formed

step 7- H2O is added to Furmarate, which results in Malate

step 8- Malate is oxidized, NAD+ is added, and it results in the formation of NADH+. The product is Oxaloacetate

Oxidative Phosphorylation
a lot of ATP is formed 26-28 molecules
Chemiosmosis

ATP synthesis

H+ go back down the concentration gradient

Creates ATP

Electron Transport Chain

an electrochemical gradient that leads to the creation of ATP

Complexes I, III, IV

Complex II

FADH2 transfers electrons

their job

pump H+ against the concentration gradient in the intermembrane space

the energy used coms from the energy released from the electrons being transferred down the ETC

are H+ pumps

located in the inter mitochondrial membrane

Pyruvate Oxidation
pyruvate is oxidize, then the electrons are transferred to NAD+ to form NADH

Acetyl Coenzyme A is formed

Glycolysis
Fermentation

Alcohol Fermentation

NADH donates its electrons to a derivative of pyruvate

carboxyl group is removed from pyruvate and released in as carbon dioxide

a two-carbon molecule called acetaldehyde

regenerating NAD+ and forming ethanol

pyruvate decarboxylase and alcohol dehydrogenase

plant tissue, yeast, microorganisms

occurs in production of bread, beer, wine, vinegar

Lactic Acid Fermentation

NADH transfers its electrons directly to pyruvate

glucose is converted to lactate and cellular energy

breaks down glucose into two molecules of pyruvate
cytoplasm

has two phases

Energy Payoff Phase

step 6- 1 G3P is oxidized by the transfer of electrons to NAD+, and forming NADH. Using energy from the redox reaction, a phosphate group, is then attached to the oxidized substrate, making 3-Biphosphoglycerate.

step 7- the phosphate group is transferred to ADP in an exergonic reaction.G3P is then oxidized to the carboxyl group, creating 3-Phosphoglycerate

step 8- Phosphoglyceromutase is used to relocate the remaining phosphate group

step 9- Enolase causes a double bond to form in the substrate by extracting a water molecule, creating phosphoenolypyruvate (PEP)

Energy Investment Phase

step 1- adding a phosphate from ATP to Glucose to form Glucose6p by using the enzyme Hexokinase

step 2- converting Glucose6p into Fructose6p

step 3- * Enzyme PFK is used to convert Fructose6P to Fructose1, 6 Biphosphate

step 4- 6 carbon sugar splits into two molecules of 3 carbon. Each of them forming DHAP and G3P

step 5- conversions between the DHAP

Function: Photosynthesis

formed when 100 or more monosaccharides are bonded together through glycosidic linkages

Floating topic

amino acid chains and polypeptide backbone held together by

alpha helices, beta pleated sheets

Provides

Can be attached to

Secondary

hydrogen bonding

water properties
universal solvent

water is a polar molecule

water expansion when frozen, denser as liquid than solid

ice has spaced-out lattice structure

ice to float

aquatic life can survive under frozen water

high heat of vaporization

amount of energy to convert 1g or a substance from a liquid to a gas

organisms regulate body temperature by sweating

hydrogen bonds to be broken

high specific heat

amount of heat needed to raise the temperature of 1 gram of a substance 1 degree Celsius

water has highest specific heat of an liquid

hydrogen bonds breaking and reforming

adhesion

water molecules attracted to each other

ex. water move up stem of a plant

cohesion

water molecules attracted to other substances

sharing of H atom
partial positive charges that attract partial negative charges

among H2O molecules

relatively strong
relatively weak

only in

Is attached to the

Surround

Envelope

Biological Molecules

Bonds

ionic bonds
covalent
polar

hydrophillic

unequal sharing of electrons

O-H, S-H, N-H, C-O

Include

Nucleic Acids
carry genetic information which is read in cells to make the RNA and proteins by which living things function
Example

DNA, RNA

Nucleotides

nucleic acids

RNA ribonucleic acid)

DNA (deoxyribonucleic acid)

DNA Replication

dna synthesis

helicase

topoisomerase

alters the supercoiling of double-stranded DNA

SSB (single strand binding proteins)

stabilize the un-wound parental strands

primase

DNA polymerase III

sliding clamp protein

converts the DNA polymerase III from being distributive (falling off) to processive (staying on)

DNA Polymerase I

DNA ligase

seals up the sequence of DNA into two continuous double strands

removes the RNA primer and replaces with DNA nucleotides

adds complementary nitrogenous base to daughter strand

leading strand

binds to the leading strand and adds new complementary nucleotide bases (A, C, G and T) to the strand of DNA in the 5’ to 3’ direction

lagging strand

numerous RNA primers, made by the primase enzyme, bind at various points along the lagging strand

chunks of DNA are then added to the lagging strand also in the 5’ to 3’ direction

Okazaki fragments

binds to each strand of DNA at the replication fork and synthesizes a short (3 to 10 base) strand of RNA

primer

provides a strand end for DNA polymerase to add bases to

is an enzyme that catalyzes DNA strand separation

breaking hydrogen bonds between strands

creating a replication fork/bubble for replication to begin

semi-conservative model of replication

The two strands of the parental molecule separate, and each functions as a template for synthesis of a new, complementary strand

Pyrimidines

Thymine (pairs with Adenine in DNA, Uracil (pairs with Adenine in RNA), and Cytosine (pairs with Guanine)

Purines

Adenine (pairs with Thymine in DNA, Uracil in RNA) and Guanine (pairs with Cytosine)

A-T form two hydrogen bonds C-G forms 3 hydrogen bonds

The amount of Adenine equals the amount of Thymine, the amount of Guanine equals the amount of Cytosine

carries genetic information

synthesize proteins

replicates itself

Include 3 Parts

5 Carbon Sugar

Deoxyribose

Ribose

Nitrogen Base

includes phosphodiester bonds

Cytosine

Thymine

Guanine

Adenine

Lipids
serve as structural components of cell membranes, as energy storehouses, and as important signaling molecules
3 Main Groups

Steroids

increase membrane fluidity and serve as signaling molecules

Phospholipid

hydrophillic head, 2 hydrophobic tails

“kinks” in their tails push adjacent phospholipid molecules away, which helps maintain fluidity in the membrane

the structural components of the cell membrane (phospholipid bilayer)

Fat (Triglycerides)

Can Be

Saturated

only single bonds between neighboring carbons in the hydrocarbon chain, saturated with hydrogen

are solid at room temperature

Unsaturated

trans isomer

H atoms on opposite sides of molecule

cis isomer

H atoms on same side of molecule

Presence of double bonds can create cis/trans isomers of fatty acids

stay liquid at room temperature

Proteins
Can Be

Quaternary

several protein chains or subunits into a closely packed arrangement

all prior bonds, van der waals

Tertiary

Subtopic

polar covalent, ionic, hydrophobic interactions, and R-group disulfide bonds

Primary

amino acid chain

peptide bonds

Hemoglobin

Enzymes

Are Chains of

Amino Acids

Known As

Polypeptides

Carbohydrates
serve as fuel and building material
Consisting of 2 or More Sugars

Polysaccharide

Starch

Plants

Glycogen

Formed of Alpha Glucose monomers connected through 1-4 glycosidic linkages

Can be Found Within

Animals

Used For

Storage of Energy

Consisting of 2 Sugars

Disaccharide

formed when a dehydration reaction joins two monosaccharides

Lactose

Sucrose

Consisting of 1 Sugars

Monosaccharide

Examples

Glucose

composed of alpha and beta isomers

Fructose

Can be

All cells have

Cells

most basic unit of life

Membranes
movement of substances in and out of the cell

Protein

Integral Membrane Proteins

Peripheral Membrane Proteins

Glycoprotein

Carbohydrates

Glycolipid

Lipids

Cholesterol

Phospholipid Bilayer

Amphipathic

Hydrophilic Head

Glycerol

Phosphate Group

Two Hydrophobic Tails

Unsaturated Fatty Acid

double bonds between carbons

Cis Fatty Acids

H atoms are on same sides

Trans Fatty Acids

H atoms are opposite

Saturated Fatty Acid

no double bonds between carbons

Transport

Passive Transport (high to low concentration)

no energy

Osmosis

contractile vacuole

pumping water out

taking water in

water crosses the the cell membrane

Hypertonic

Plasmolyzed

Shriveled

Isotonic

Flaccid

Normal

Hypotonic

Turgor

Lysed

Facilitated Diffusion

substances cannot cross membrane on their own

Hydrophobic Molecules

Carrier Protein

shapeshifts to help different molecules

Hydrophilic Molecules

Channel Protein

uses channel for molecules and specific solutes

Simple Diffusion

substances easily cross cell membrane

Active Transport (low to high concentration)

energy

large amounts of substances pass through membrane (vesicles)

Endocytosis

movement into the cell

Receptor Mediated Endocytosis

Pinocytosis

Phagocytosis

Exocytosis

movement out of the cell

smalls amounts of substances pass through proteins (pumps)

Sodium Potassium Pump

conformation/changes in shape

2K+ are brought in against concentration gradient

3Na+ kicked out against concentration gradient

Cytoplasm

Organelles

Prokaryotic Organelles

Nucleoid

genetic material, is not membrane bound

Pili

Motion, attaching to objects, transfer of genetic material

Are not membrane bound

Found in Eukaryotic and Prokaryotic cells

Flagella

Located on the outside of the cell

Allows the cell to move

Ribosomes

Protein Synthesis

Rough ER

Golgi Complex

Glycosylated

Point Mutations

Insertions and Deletions

Frameshift Mutations

Missing/Extra Amino Acid

Extensive Missense

Immediate Nonsense

Base Pair Substitution

Missense

wrong amino acid is produced

Silent

there is no effect on amino acid produced

Nonsense

premature stop codon is present

DNA

RNA

tRNA

Amino Acids

mRNA + tRNA

tRNA on P-site

moves along mRNA making polypeptide chain

Protein is Released

all parts detach for each other

Exit Site

B site

A site

Anticodon

mRNA

Codon

Stop Codon

Start Codon

Uracil

Thymine

Organelles found only in Eukaryotes

Chloroplast

Produces Sugar

ER

Smooth ER

Storage for protein and lipids

Rough Er

Storage for Protien

Lysosomes

Breaks down cell waste

Vacuoles

Storage

Golgi apparatus

Storage and Transport

Mitochondria

evolved from bacteria

Nucleus

Contains genetic material

Prokaryotes
Archea

extremophiles

methanogens

methane as waste product

thermophiles

halophiles

Bacteria

peptidoglycan (in cell walls)

Eukaryotes
Plant Cells

Photosynthesis

Energy

Light Reactions

Photosystem II P680

CAM Photosynthesis

Malic Acid

Vacuole

takes place at night

H20 loss

C4 Photosynthesis

PEP Carboxylase

Oxaloacetate

Malate

CO2 + Pyruvate

Bundle Sheath Cells

Calvin Cycle

CO2

ADP + P

Glucose

NADP

Stroma

Light-dependent Reactions

Energy from Sunlight

O2

ATP

NADPH

Water

Thylakoid Membrane

Chloroplasts

Chlorophyll

Natural Pigment

Animal Cells