anatomy exam 2 Flashcards
order of transcription
dna transcribes mrna translation to protein
transcription takes place in the ? and is completed by?
nucleus and rna polymerase
translation takes place in the? using?
cytoplasm, ribosomes
basic structure of a human gene
1) initiation- rna polymerase bond to promoter
2) elongation- rna polymerase reads dna at synthesizing mRna
3) Termination- Rna Polymerase reaches termination sequence and reaches it’s stopping point
initiation (1 protein translation)
tRna delivers the first amino acid to start the protein (polypeptide). Another tRna binds to the A site and delivers the second amino acid for the growing protein it just slides down the chain.
1) ribosome clamping onto mRna
2) start codon (aug) recognized
3) tRna brings 1st amino acid
elongation (2 protein translation)
1) ribosome slides down mRna
2) tRna delivers amino acid
3) Form peptide bonds between amino acids
termination (3 protein translation)
1) it will reach a stop codon
2) This is where the process ends
What type of material can freely diffuse through the plasma membrane? And what types cannot?
freely move= small and nonpolar/ uncharged
channels= small and polar/ charged
How do large molecules that cant fit through membrane channels transport in and out of the cell?
-By carrier mediated transport which is when they physically grab and carry across membrane (molecule by molecule for molecules more variable in availibilty like glucose)
- vestibular transport- grab across a membrane in bulk
osmotic pressure
how much force is needed to stop osmosis
osmosis goes from
high free water to low free water or low solute to high solute
passive transport
no energy spent (diffusion and osmosis)
active transport
requires energy
Nucleus
Large membrane bound Structure; contains DNA and aIso Enzymes For Dna replication and DNA transcription
Nuclear pore
Opening in the nuclear membrane where the double membrane fuses to produce pores; allows movement of mRNA into the cytoplasm
ribosome
an intercellular structure made of both rna and proteins and is the site of protein synthesis in the cell
mitochondria
organelle found in large numbers in most cells that generate most of the chemical energy needed to power the cells biochemical reactions
Endoplasmic reticulum
Rough- membranous organelles with fixed ribosomes attached to it; site of production of proteins for export from the cell or for incorporation in cell membrane
smooth- channels of membranous tubules that contain enzymes to synthesize carbohydrates and lipids
golgi apparatus
stacks of interconnected flat membranous sacs; packages proteins for insertion into the plasma membrane or for exocytosis into the interstitual fluids
cytoskeleton
structure that helps maintain the shape and structure of the cell and is responsible for locomotion of cell itself and the movement of various organelles with it
vacuoles
store nutrients and water in which a cell can rely on for it’s survival. Stores salts, minerals, pigments, and proteins within the cell. Also facilitates endo and exocytosis
centrosomes
regulates cell motility, adhesion and polarity in interphase and facilitated the organization of the spindle poles during mitosis
for parent cell to divide
1) Duplicate the cellular components
2) replicate dna
3) growth- nutrients available in environment to grow
mitosis
division of the nucleus seperate duplicated chromosomes
cytokinesis
division of the cytoplasm
what is the goal of cellular respiration ( aeribobic respiration)
To take energy stored in glucose molecules to power the process of making atp so the end product of cellular respiration is atp
When the cell is not dividing (is in Go), will its DNA be packaged as chromatin or chromosomes? Explain why.
Chromatin loosely packed dna
- need access to genes for transcription to occur dna replication
When the cell is dividing, will its DNA be packaged as chromatin or chromosomes?
Easily moveable when condensed chromosomes
How does the cell regulate its progression through the cell cycle?
Regulation of cdk by phosphorylation and the binding of regulatory proteins such as cyclins
What could happen if the regulation of the cell cycle is faulty?
Can lead to diseases such as cancer because cells can divide without order and accumulate genetic errors that can lead to a tumor
Aerobic respiration
cellular function that require oxygen in the reaction
four major steps of aerobic respiration
glycolysis
citric acid cycle
electron transport chain
oxidative phosphorylation
what is the goal of glycolysis
to split glucose into two pyruvate which each have 3 carbons as we do that we harnest electron for the electron transport chain
what is the goal of the citric acid cycle?
breaking down pyruvate to release electrons for the ETC
what happens during CAC
pyruvate enters mitochondria
- broken down to release electrons
- electrons are carried by carriers to the ETC
- CO2 is produced from C and O is pyruvate
what is the goal of ETC and oxidative phosphorylation?
synthesize atp using energy from electrons moving in ETC
anaerobic cellular respiration
No O2 present/ not enough O2
fermentation (extension of glycolysis)
- lactic acid
why try to use aerobic respiration?
produces way more atp per glucose anaerobic produces harmful waste
Mitosis stages
prophase
prometaphase
metaphase
anaphase
telophase
interphase
G1,s,G2
g1
G1 is the stage where the cell is preparing to divide.
s
when DNA replication and much of the DNA repair activity occurs in cells.
g2
a period of rapid cell growth and protein synthesis during which the cell prepares itself for mitosis.
