Kategóriák: Minden - signaling - receptor - transcription - regulation

a Joy Aniede 6 éve

121

Bio Concept Map

The intricate regulation of gene expression involves various mechanisms in both eukaryotic and prokaryotic systems. In eukaryotes, proximal and distal control elements work with general and specific transcription factors to modulate transcription levels.

Bio Concept Map

Repressor binds to the operator (active)

Operon OFF

operon ON

EXAM 2

Integral: Proteins that are inside and outside the phospholipid bilayer; transmembrane protein

Carrier

Pinocytosis:cell continually gulps droplets of extracellularfluid

Phosphatase: removes a phosphate group

Phosphodiesterase: converts CAMP to AMP

Adnylyl cyclase: converts ATP to CAMP

BIG IDEA III

Cell Cycle

Recombinant DNA

Egg cell donor
Mammary cell donor
Egg cell from ovary

Grown in culture

Implanted in uterus of a third sheep

Embryonic Development

Gene Regulation

Transcription & Translation

DNA Structure & Replication

BIG IDEA II

Photosynthesis

PEP Carboxylase
CO2

Oxaloacelatate (4C)

Malate (4C)

Pyruvate (3C)

PEP (3C)

Calvin Cycle

Sugar

Vascular Tissue

Respiration

Metabolism

BIG IDEA I

Cell Communication

Biological Membrane

Cell Structure

Origin of Life

Biological Molecules

Chemistry for Biology

Biological Hierarchy

BIOLOGY 311C: introduction to structure & function, energy flow, and transmission & expression of genetic information in the living systems

EXAM 3

EXAM 1

Protein Kinase: adds a phosphate group

MACROMOLECULES

CELLULAR RESPIRATION

Glycolysis

Glucose

Glyceraldehyde-3-P
Pyruvate

Acetyl CoA

Citric Acid Cycle

Oxidative phosphorylation

Fats

Fatty Acids

Glycerol

Carbohydrates

Sugars

Proteins

Amino Acids

Expresses protein that stimulates the cell cycle

Hyperactive Ras signals excessive protein

Produces an uncontrolled cell growth and leads to cancer

CELL CYCLE

Cyclin-Dependent Kinases: only active when bound to specific cyclins, always present in the cell

Cyclins: protein

Cancer

Oncogene: 'onco' means tumor
Ras: a G-protein
p53: tumor repressor gene
Proto-oncogene: normal cell growth and division

Interphase

Mitosis
Prophase: chromosomes condenses, nucleoli begins to break down and disappear

Prometaphase

Metaphase: chromosomes align in the center of cell

Anaphase: sister chromatids move to the opposite ends of the cell

Telophase: spindle fibers disperse, nuclear envelope forms around a group of chromosomes at each pole

Cytokinesis: cytoplasm divides

Meiosis
Meiosis II

TelophaseII

Anaphase II

Metaphase II: Chromosomes align in the center of cell

Prometaphase II

Prophase II

Meiosis I

Prophase I: chromosomes condenses, nucleoli begins to break down and disappear

Prometaphase I

Metaphase I: homologous chromosomes align parallel in the center of cell

Anaphase I: homologous chromosomes move to the opposite ends of the cell

Telophase I: spindle fibers disperse, nuclear envelope forms around a group of chromosomes at each pole

Cytokinesis

Plants: cell plate forms

Animals: cleavage furrow

G2: more growth
S: DNA replication
G1: growth occurs

GENE REGULATION

EUKARYOTIC

Specific Transcription Factors
High Levels of Transcription

Activatiors

Attach to the enhancers

Activates to the DNA binding protein: bends and folds to gene to reach the promoter

General Transcription Factors
Low Levels (basal) Transcription
Distal control elemeents
Proximal control elements
DNA packaging
Nucleosome

Tight Helical Fiber

Looped Domains

Metaphase Chromosome

PROKARYOTES

Trp operon
Tryptophan Present

Repressor is inactive (not enough tryptophan avaliable)

Operon ON

Lac operon
Lactose Present

Yes

Repressor binds to allolactose (inactive)

Glucose Present

Adenylyl cyclase: inactive

cAMP levels low

cAMP inactive

operon OFF (basal)

No

Adenylyl Cyclase: active

cAMP levels high

CAP active

CELL SIGNALING

Enzymes

Signal transduction pathway: amplification of message

Cellular responses
Example: Produces transcription factors

p53: (tumor suppressor gene) produces protein that inhibits the cell cycle as a transcription factor

defective p53 as a missing transcription factor cannot activate transcription, causes cancer

Transduction
CAMP: second messenger

Protein Kinase A

Phosphorylation Cascade

Reception signal molecule binds to receptor
Tyrosine Kinase Receptor

Signaling molecule binds to kinases, makes a dimer

Produces ATP and adds 6 phosphate groups

Activates relay protein kinases

Signaling molecule

G protein coupled receptor

G protein

Ras: type of G-protein

Adenylyl Cyclase

MEMBRANE

Exocytosis: cell secretes certain molecules by the fusion of vesicles with the plasma membrane

Membrane fluidity: unsaturated tail and cholesterol

Diffusion: moving from high to low concentration

Subtopic
Molarity
Hypotonic: lower solute concentration
Animal

Shriveled

Normal

Lysed

Plant

Flaccid

Plasmolyze:

Turgid: normal; plant cell is hypertonic to the outside

Isotonic: same concentration
Hypertonic: higher solute concentration
Simple: no need for protein or ATP
Small non-polar molecules: CO2, O2
Active: needs protein and ATP

Endocytosis: cell takes in molecules by forming new vesicles from the plasma membrane

Receptor-mediated: cell acquires bulk quantities of specific substances
Phagocytosis: cell engulfs particles

Protein

Peripheral: touch the outside of the phospholipid bilayer

Phospholipid bilayer