Categories: All - signaling - receptors - translation

by Adanna Onyeka 2 years ago

205

Final Concept Map

The intricate process of cell signaling encompasses various mechanisms by which cells communicate and respond to signals. Fundamental to this process is the release and reception of signals, which can occur over long distances via hormonal signaling or locally through synaptic and paracrine signaling.

Final Concept Map

Another function that was not added until later is cell signaling, with examples like the kinase receptors

The cell membrane is composed of many lipids, some with glycerol (a three carbon molecule) acting as the backbone

Gene regulation occurs in the nucleus of the cell because this is where transcription occurs

Cellular Respiration

Oxidative Phosphorylation

Chemiosmosis ATP Synthesis
concentration gradient

transport protein - ATP Synthesis

Electron Transport Chain
Inner mitochondrial membrane

Anerobic respiration

Lactic Acid
Alcohol Fermentation

Substrate level phosphorylation

Pyruvate Oxidation

c

Citric acid cycle begins

Citrate

Isocitrate

a-ketoglutarate

Succinyl CoA

Succinate

Fulmarate

Malate

Oxaloacetate

Glycolysis

Energy Payoff Phase
NAD+

Pyruvate

Water/H2O

NADH

Protons

Phosphate

Electrons

Energy Investment Phase
ADP
ATP

Replication forks- located at each end of the replication bubble

Topoisomerase- enzyme

DNA Replication

Double stranded DNA- with a complimentary, antiparallel structure

Helicase- enzyme
Single-stranded DNA

Single-stranded Binding Protein (SSBs)- enzyme

Primase-enzyme

Lagging strand

Okazaki fragments

DNA ligase- fills in the gaps left by removed RNA primase with nucleotides complimentary to the parent strand

Leading strand

Parental DNA

DNA polymerase III

Daughter strand

5' to 3' direction

Chargaff's rule- states purines and pyrimidine must be paired with one another, specifically the same proportion of adenine to thymine and guanine to cytosine

sliding clamp

Origin of replication: Sequence of nucleotides that indicates the beginning of DNA replication

Replication bubble
Bidirectional forks- located at each end of the replication bubble

Fast and accurate

Concept Map 3

Transcription

Termination
the pre-mRNA is noticed by ribonuclease an amino acid which cuts the pre-mRNA from the DNA

a 5'cap is added to the pre-mRNA

a 3' poly-A tail is added by polyA polymerase

the pre-mRNA is now ready to undergo processing

RNA Processing

introns are cut out by spliceosome

exons are brought together through spliceosome

mature mRNA is created and ready for translation into proteins

exon-material containing suitable nucleotides for protein function

intron-filler material

Elongation
RNA polymerase ii bind to the template strand of DNA 3'-5'

RNA polymerase ii unwinds DNA and then adds RNA nucleotides

the RNA being created resembles the non-template strand of DNA 5'-3'

pre-mRNA strand is now created 5'-3'

Initiation
Promoter

start point-point of transcription

TATA box-using for recognition of transcription factors

Transcription Factors-used to RNA polymerase ii can bind in the correct position

RNA Polymerase ii-add RNA nucleotides

RNA polymerase ii and Additional transcription factors bind in order to make a transcription initiation complex.

Concept Map 2

Concept Map 1

Prokaryotes

Prokaryotes - A type of organism that is single celled, lacks a nucleus, and contains no membrane bound organelles.

Metabolism
Facultative anaerobes

This kind of organism utilizes aerobic respiration when oxygen is present, but can also use fermentation when oxygen is not.

Obligate anaerobes

Organisms that cannot tolerate environments with oxygen present as it would lead to cell death and instead utilize fermentation anaerobic respiration.

Obligate aerobes

Organisms that require oxygen for cell respiration

Common Structures
Nucleoid

Prokaryotic cells don't have a membrane bound organelle for their DNA, rather they have a recognized region where DNA is located known as the nucleoid.

Materials Present

Controls the synthesis of proteins and provides essential messenger functions for DNA.


Its structure varies from DNA in that it has ribose sugars instead of deoxyribose, is single-stranded, and has uracil instead of thymine

Bacterial Genome

Endospore

Endospores are essential for bacteria living under extreme conditions. It protects the DNA of the cell by making a dormant and resistant cell that can survive various circumstances.


As the rest of the cell disintegrates, the DNA is protected by the multiple layers of cell wall material surrounding it, forming the endospore.

Gas vacuoles

Gas vacuoles assist in buoyancy for flotation in aquatic environments.

Capsules and slime layers

This structure surrounds the cell wall of bacteria as a sticky later of polysaccharide or protein, and helps the cell for adhesion and protection.

Flagella

The flagella is important for the cell's motility, and contains a hook a basal body. It can exist either around the surface of the cell, or be concentrated in one area.

Ribsomes

Ribosomes are present in both prokaryotes and eukaryotes, and are essential for protein synthesis.

Cytoplasm

The cytoplasm consists of gel-like cytosol, water based solution with ions and small molecules, and makes up the internal part of the cell inside the plasma membrane.

Cell wall

Present in all prokaryotes, the cell wall maintains the cell's shape, and provides protection and support. This structure is made of modified sugars with short polypeptides called peptidoglycan.



Peptidoglycan

This substance that makes up the cell wall is unique to bacteria, and can be used to target them specifically.

Fimbriae and pili

Fimbriae are short abundant structures used by bacteria to stick to other bacteria, while longer pili assist in transferring DNA between cells.

Plasma membrane

The plasma membrane is a selectively permeable barrier for the cell. It provides boundaries between the inside of the cell and its environment, facilitates the transport of nutrients and waste, and is where metabolic processes occur.


Factors of fluidity

The weak Van der Waal forces present in the membrane allow for the movement of lipids. The fluidity of the membrane however is determined by a few factors.


Cholesterol embedded within the plasma membrane allows for the regulation of the movement in phospholipids by reducing movement at moderate temperatures and preventing the overpacking of saturated fatty acids at low temperatures by acting as a buffer.

Types of fatty acids present

The ratio of unsaturated fatty acids to saturated fatty acids also affects the fluidity of the membrane. Saturated fatty acids lack the structural kink that is present in unsaturated fats, allowing the phospholipids to pack together more tightly, and resulting in a more rigid structure.




Temperature

At a specific lower temperature, the membrane's phospholipids change from their more liquid, crystalline phase, to a more gel-like phase.


Transport of molecules

The membrane being selectively permeable means only certain molecules can pass through without assistance.


Molecules that can transport across the membrane


Molecules that cannot

Specific structures

The plasma membrane is made up of an amphipathic phospholipid bilayer, with hydrophilic heads bordering the outside and inside of the cell, and the hydrophobic tails making up the interior of the membrane.


This arrangement is held together by weak Van der Waal forces that allow lipids to move within the membrane and provides fluidity.


The membrane also consists of proteins located on the surface (surface proteins), within the membrane (integral proteins), and with chains of polypeptides (glycoproteins).



Types
Archaea

A category of prokaryotic micro-organisms

Methanogens

Another prokaryote in the archaea domain are methanogens. These can be found in hydrothermal vents, the guts of animals, and wetlands. They are anaerobic, meaning oxygen is poisonous to them, and remove excess hydrogen.

Extreme thermophiles

This kind of prokaryote can thrive in high temperatures that few other organisms can survive in. They are commonly found in many extreme temperature environments such as hot springs and hydrothermal vents.

Extreme halophiles

These kinds of archaea are able to thrive in extremely saline environments, referred to as extreme as very little amounts of organisms can survive in similar conditions.

Bacteria
Nutrition Modes
Heterotrophs

Chemoheterotroph

Chemoheterotrophs utilize carbon from organic compounds, and are characteristics of many prokaryotes.

Photoheterotroph

The prefix photo refers to light, which this mode utilizes for energy. This trait is unique to certain aquatic and salt thriving prokaryotes. Since its a heterotroph it utilizes carbon from organic compounds.

Autotrophs

Chemoautoroph

Inorganic chemicals

This mode, as an autotroph, means a prokaryote gets its energy from inorganic chemicals.

Photoautorophs

Light

Organisms that utilize light to synthesize organic molecules are known as photoautotrophs, such as cyanobacteria.

Cell membranes

Structures
made of

proteins

transport, enzymatic activity, cell-cell recognition, signal transduction, intercellular joining, and attachment to the cytoskeleton and extracellular matrix (ECM)

Transmembrane proteins have an extracellular and cytoplasmic side

Ion channels

sodium potassium-pump, potassium channel, sodium channel

Gated (stretch-gated, ligand-gated, voltage-gated)

Un-gated (always open)

phospholipid bilayer

hydrophobic tail (fatty acid chain) and hydrophilic head (polar) which help control membrane fluidity

are

selectively permeable

Function
barrier, support, protection

separates organism from the environment

transport

larger molecules

exocytosis

endocytosis

receptor-mediated

phagocytosis

pinocytosis

smaller molecules

osmosis/diffusion

Hypertonic solution

plasmolyzed (plant loses water)

Hypotonic solution

turgid(normal in a plant cell)

Isotonic

active transport

ex:sodium-potassium pump

low->high concentration

protein pumps

facilitated diffusion

channel proteins are needed

passive transport facilitated by proteins

Floating topic

Biomolecules Molecules created by living organisms.

hydrolysis
dehydration reaction
Proteins
Polypeptide

Quaternary: 2 or more polypeptides form a functional protein through R group interactions

Tetramer: 4 PPs

Trimer: 3 PPs

Dimer: 2 PPs

Monomer: 1 PP

Tertiary: R groups interact to from 3D shape

Disulfide bond

Ionic bonds

Hydrophobic interactions

Hydrogen bonds

Secondary: Main chains form hydrogen bonds

Beta-pleated sheet

Alpha helix

Primary: Amino acids connected through peptide bonds

Amino acids

Side chain: R group

Basic: Complete positive charge

Acidic: Complete negative charge

Nonpolar: Has H, CH, or carbon ring

Polar: Has OH, SH, or NH groups

Main chain: Amino & carboxyl groups

Lipids
Phospholipids

Form bilayer in water

Hydrophilic head: Phosphate group

Hydrophobic tail: Glycerol & 2 Fatty acids

Steroids

Testosterone

Cholesterol

LDL: Carries excess to blood vessels (bad)

HDL: Carries excess to liver for excretion (good)

4 fused rings

Triglycerides

Energy storage

3 Fatty acids

Unsaturated

Trans: H on different sides of double-bonded carbons

Cis: H on same side of double-bonded carbons. Has a kink

Liquid at room temp

One or more double bonds & H atoms are notat every position

Saturated

Solid at room temp

No double bonds & H atoms at every position

Glycerol

Nucleic Acids
Gene expression
RNA

nitrogenous base

Cytosine (C) & Uracil (U)

ribose sugar

DNA

nitrogenous base

Pyrimidines

Cytosine (C) & Thymine (T)

Purines

Adenine (A) & Guanine (G)

phosphate

deoxyribose sugar

Carbohydrates
Complex

Structure polysaccharides

Chitin

Cellulose

Beta glucose & 1-4 glycosidic linkages (no branching)

Storage polysaccharides

Dextran

Starch

Amylase

Alpha glucose & 1-4 and 1-6 glycosidic linkages (some branching)

Amylose

Alpha glucose & 1-4 glycosidic linkages (no branching)

Glycogen

Alpha glucose & 1-4 and 1-6 glycosidic linkages (lots of branching)

Simple (Sugars)

Disaccharides

Maltose

Lactose

Sucrose

Monosaccharides

Hexoses: 6-carbon

Fructose

Galactose

Glucose

Beta: OH is above the ring

Alpha: OH is below the ring

Pentoses: 5-carbon

Deoxyribose

Ribose