Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
188 Cards in this Set
- Front
- Back
|
Numbers of cells for bacteria, archae, euk |
unicellular for bacteria and archae, multi for euk
|
|
|
prok or euk for bacteria, archae, euk?
|
bacteria and archae are prok; eukarya is euk
|
|
|
importance of having high SA to V ratio
|
speed of vital functions: absorption of nutrients and expelling waste
|
|
|
- Cell size of euk vs. prok cell
- Presence of organelle in euk vs. prok cells - oxygen requirement for euk vs. prok |
euk is larger
euk has organelles; prok don't euk generally need Oxygen for celluluar respiration prok generally don't |
|
|
Main difference between euk vs. prok
|
presence of organelles
|
|
|
What is an organelle?
|
membrane bound compartment responsible for a specific, vital function
|
|
|
What's cytoplasm composed of?
What's the function? |
water, ion, nutrients, waste
site of chemical reaction within the cell |
|
|
What's the function of nucleolus?
|
make rNA
storage of DNA |
|
|
What's ribosome made of?
|
rRNA and protein
|
|
|
Main function of sER
- in liver? |
production of lipids
liver - make detoxifying enzymes |
|
|
Main function of rER
Describe the pathway of where protein moves from rER |
protein synthesis
rER --> sER --> golgi |
|
|
Main function of golgi?
|
modify, repackage, tag for eventual destination
|
|
|
Lysosome is a type of what?
Main function of lysosome? What is apoptosis? |
Vacuole (large sac)
Repair - digestive enzyme with low pH - cell's suicide |
|
|
What is a Peroxisome?
What is its function? |
another type of vacuole
digest fatty acids and amino acids degrade toxic hydrogen peroxide (metabolic waste product) to water and oxygen gas |
|
|
What is unusual about mitochondria compared to other organelles?
|
- double membrane
- DNA of its own - self replicate |
|
|
What is endosymbiotic theory?
|
mitochondria are the evolutionary remnants of bacteria that were engulfed by other cells long ago in evolutionary time
|
|
|
What are 3 fibers that make up a cytoskeleton?
|
microtubules
microfilaments intermediate filaments |
|
|
what is a microtubule?
|
hollow, made up of tublin, responsible for structural support, maintain cell shape
|
|
|
what is a microfilament?
|
made up of actin, assist cellular movement
|
|
|
intermediate filament
|
composition varies, structural support for the cell
|
|
|
Cilia
|
hairlike structure, synchronized motion, constantly moving
|
|
|
flagella
|
tail for movement
|
|
|
what is composition and function of cell wall?
|
cellulose (fiber)
protect the cell from its environment and from dessication |
|
|
chloroplast - what does it contain? what is its vital function?
what is unusual about chloroplast? |
green pigment chlorophyll, process of photosynthesis
own DNA, replicate independently |
|
|
central vacuole
|
reserve storage for water, nutrient, and waste products
- takes up the majority of space within a plant cell |
|
|
cell membrane - function?
- composition? |
- selectively permeable, barrier between cell and its external environment
- PBL |
|
|
PBL - head composition?
|
head - glycerol, phosphate (polar)
tail - non polar (hydrophobic) |
|
|
what is fluid mosaic model?
|
proteins, carbohydrates embedded between PBL
|
|
|
where is cholestrol embedded and what is its role?
|
in the interior of PBL; to regulate fluidity of the membrane
|
|
|
purpose of proteins scattered in the membrane?
|
transport, enzymatic activity, cell adhesion, communication, receptors for specific substances
|
|
|
what is passive transport?
|
without energy; moving from area of high concentration to an area of low concentration; occur spontaneously
- diffusion, osmosis |
|
|
what is active transport?
|
with energy - require ATP
- moving solutes against CG; |
|
|
what is a concentration gradient?
|
relative comparison of solutes and over-all concentration of fluids inside and outside the cell
|
|
|
what is diffusion?
|
movement of small solutes down their concentration gradient
- more from less - slow by nature - affected by temperature, size of molecule, how large the CG is - continues until equilibrium is met |
|
|
what is osmosis
|
specific type of diffusion moving down its concentration - water
|
|
|
what is isotonic solution?
|
no net movement of water
concentration of solutes inside and outside the cell are equal |
|
|
what is hypotonic solution?
|
more water and less solute relative to what is being compared to
- water goes into the cell, which may burst (lysis) |
|
|
what is hypertonic solution?
|
solution that has less water and more solute relative to what is being compared to
- water leaves the cell, which shrivels (crenation) |
|
|
What is bulk transport?
|
not limited by the size of molecule; can move large molecules
endocytosis and exocytosis |
|
|
what is endocytosis?
what is pinocytosis? what is phagocytosis? |
bring items into the cell; surround the item to form a vesicle which pinches off and moves into the cell
pinocytosis - liquids moved into the cell this way phagocytosis - large items (other cells) are brought into the cell this way |
|
|
exocytosis
|
transport molecules out of the cell; vesicles containing the substance to be transported outside the cell fuses with the membrane and is released
|
|
|
How does enzymes work and what are they essential for?
|
lower activation energy; homeostasis
|
|
|
are most enzyme reactions reversible?
|
yes
|
|
|
area on the enzyme where substrate interact
|
active site
|
|
|
what facilitates the reaction between the enzyme and substrate?
|
binding that results in conformational change in shape, inducing a tighter binding between the enzyme and substrate
|
|
|
what are cofactors?
|
ions that assist in substances to work properly
|
|
|
what are coenzymes?
|
organic molecules usually derived from vitamins obtained in the diet
|
|
|
what happens to the rate of reaction if amount of substrate increases?
|
also increase
|
|
|
how does temperature affect enzymatic activity
|
each enzyme has optimal termpature for functioning - in humans usually 37C.
denaturation at increasing temperature, pH can also lead to denaturation (irreversible) |
|
|
what's the difference between competitive and non-competitive inhibitors?
|
competitive - molecule resembling a substrate in shape
non-competitive - bind to allosteric sites, changing the shape of active site and decreasing the functioning of the enzyme |
|
|
where is green chlorophyll located in plants?
|
thylakoids - absorb solar energy
|
|
|
what lights are most valuable for photosynthesis?
|
red and blue
less useful yellow and green are reflected, making plants appear green |
|
|
What are photosystems?
|
arrangement of chorophyll molecules and other pigments in the thylakoids - absorb solar energy and facilitate the passage of electrons through carrier molecules
|
|
|
In light dependent reaction, in which photosystem is the NADP+ reduced?
|
PSI
- NADPH is used in calvin cycle |
|
|
what is the source of electrons in photosynthesis?
|
water
|
|
|
what's another name for light independent reaction?
|
calvin cycle
|
|
|
where does calvin cycle occur?
what's the purpose of calvin cycle? |
stroma of chloroplast
make sugar! |
|
|
what is stomata
|
surface of leaves which are like pores that can open and close to regulate the entrance of carbon dioxide into the plant
|
|
|
what's the first step in calvin cycle?
|
RUBP combined with CO2
|
|
|
where is ATP produced in photosystems?
|
PSII
- used in calvin cycle |
|
|
what is the eventual result of calvin cycle?
|
G3P or PGAL is released - 2 required to make glucose - make cellulose and starch
|
|
|
anabolic reactions ____ energy while catabolic reactions ____ energy
|
require, release
|
|
|
protein synthesis, nerve conduction, muscle contractions are ____ reactions
|
endergonic (break down ATP, ATP required)
|
|
|
cellular respiration is a _____ reaction
|
exergonic (make ATP)
|
|
|
how is addition of phosphate to ADP achieved?
|
substrate lvl phosphorylation
|
|
|
what is electron transport chain fueld by?
|
protons
|
|
|
in which cycles do substrate lvl phosphorylation occur?
|
glycolysis and krebs cycle
|
|
|
what is substrate lvl phosphorylation?
|
ATP synthesis is directly coupled to the breakdown of glucose - release small amounts of ATP
|
|
|
what's important about glycolysis and kreb's cycle?
|
breakdown of glucose enables production of electron carrier molecules to collect protons and electrons needed to run the ETC
|
|
|
in glycolysis, what is glucose broken down into?
|
2 molecules of pyruvate
|
|
|
where does glycolysis take place?
it happens for both ____ and ____ respirations |
cytoplasm
aerobic and anaerobic |
|
|
what is the net gain of ATP in glycolysis?
|
2
2 input, make 4 |
|
|
how is pyruvate produced from glycolysis moved to mitochondria for aerobic respiration?
|
active transport
|
|
|
what is the site of ETC?
|
inner membrane of mitochondria: cristae membrane
|
|
|
modification of pyruvate in kreb cycle
|
pyruvate decarboxylation
- oxidation of pyruvate and release of CO2 |
|
|
what is capable of entering the Kreb cycle?
|
acetyl coA
- one C lost as CO2 from pyruvate; coA is added to the acetyl group |
|
|
what does acetyl coA combine with to form a six carbon molecule?
|
oxaloacetate
forms a citric acid (5-C cmpd) |
|
|
what is the end result of Kreb cycle?
|
2 ATP, 6NADH, 2 FADH2, 4CO2
|
|
|
where does kreb cycle happen?
|
matrix of mitochondria
|
|
|
where does oxidation of pyruvate happen?
|
cytoplasm
|
|
|
how is ATP generated in ETC?
|
oxidative phosphorylation
|
|
|
how many cytochromes are in each ETC?
- where does NADH and FADH2 deliver their 2-'s? |
3
- NADH --> first - FADH2 --> second |
|
|
what is chemiosmotic theory?
|
explain how ATP is produced - energy from movement of electrons donated by NADH and FADH2 i used to pump protons into the intermembrane space creating a proton gradient
|
|
|
is energy required to pass proton through a ATP synthase?
|
no
|
|
|
how many ATP's does NADH and FADH2 make?
|
NADH - 3 ATP's
FADH2 - 2 ATP's |
|
|
how many ATP's are made through ETC, substrate lvl phosphorylation?
|
total of 32 ATP through ETC
4 through substrate lvl phosphorylation 36 ATP total |
|
|
first step in anaerobic pathway
|
glycolysis
followed by fermentation (fermentation itself doesn't make any ATP) - fermentation regenerates NAD+ needed to continue with glycolysis |
|
|
what is the net gain of anaerobic respiration?
|
2 ATP
- 2 input, 4 output |
|
|
what is pyruvate reduced to in lactic fermentation?
|
lactic acid
|
|
|
what is muscle fatigue attributed to?
|
lactic acid b/c of lactic acid fermentation
|
|
|
in alcoholic fermentation, what's pyruvate reduced to?
|
ethanol
|
|
|
amount of which nitrogenous bases are the same?
|
amt A = T
amt G = C |
|
|
how many HB bonds does A and T have?
|
2 bonds for A and T
3 bonds for G and C |
|
|
what does a single chromosome consist of?
|
one DNA double helix wrapped around specialized histone proteins that form chromatin
|
|
|
what is a chromosome?
|
compacted form of chromatin, condensed version
|
|
|
what is a centromere
|
location where replicated chromosome attach
|
|
|
what enzyme links the okazaki fragments together?
|
DNA ligase
|
|
|
name a DNA repair enzyme
|
DNA polymerase
|
|
|
during txn, RNA polymerase makes a complementary strand based on which DNA strand?
|
template strand
|
|
|
sequence of DNA that RNA polymerase recognizes
|
promoters
|
|
|
when does RNA polymerase stop txn
|
upon reaching termination sequence
|
|
|
purpose of 5'cap on mRNA
|
regulate translation
|
|
|
purpose of 3' tail on mRNA
|
prevent degradation of the RNA molecule
|
|
|
splicing exons in different seq
|
RNA splicing
|
|
|
where does translation occur?
|
cytoplasm
|
|
|
what is tRNA
|
piece of RNA folded into a specific config, shuttle appropriate aa, contains anticodon at the end complementary to the codon on the mRNA
|
|
|
what attaches first to mRNA?
|
small ribosomal subunit
|
|
|
first tRNA enters which site of ribosome?
|
P site
|
|
|
enzyme forming peptide bond between aa's in P and A sites
|
peptidyl transferase
|
|
|
what is a mutation
|
change in the coding sequence in the DNA
|
|
|
what is a missense mutation
|
one diff amino acid - change in one codon resulting in diff aa
ex. sickle cell anemia |
|
|
mechanism of txn regulation
|
coiling of chromosome physically preventing or allow the access of txn factors and RNA polymerase to the promoter regions of DNA
|
|
|
posttxn regulation
|
mRNA splicing
|
|
|
translational regulation
|
lifespan of mRNA, influenced by the length of poly-A tail added during RNA modification in the nucleus
|
|
|
post-translational regulation
|
degradation of protein immediately following synthesis; failure to properly modify the protein, rendering it useless
|
|
|
what is inborn errors of metabolism
|
faulty versions of enzymes needed for metabolism
|
|
|
what is mendel's law of segregation
|
1) for every given trait, an individual inherits two alleles for the trait
2) as an individual produces egg and sperm, the two alleles segregate so that each gamete contains only a single allele per trait. |
|
|
what is exception to mendel's law of segregation
|
male's sex allele - males contain only one X chromosome and one Y chromosome, male will not have two alleles per trait for genes on the sex chromosome
|
|
|
which sites on ribosome does first tRNA attach to?
|
P site
|
|
|
bond btwn tRNA and mRNA?
|
hydrogen bond
|
|
|
enzyme forming peptide bond between two aa's in translation
|
peptidyl transferase
|
|
|
what is a point mutation
|
single nucleotide swapped for another - single change in codon - missense mutation
|
|
|
what is a missense mutation
|
change in one aa
|
|
|
what are stem cells
|
cells yet to be differentiated
|
|
|
transcriptional regulation
|
coiling - physical prevention/ access of txn factors and RNA poly to the promoter regions of DNA
|
|
|
post-txn regulation
|
mRNA splicing/ control the rate at which mRNA leaves the nucleus
|
|
|
translational regulation
|
lifespan of mRNA - dp on length of the poly-A tail
|
|
|
post translational regulation
|
degradation of protein followed by synthesis, failure to properly modify proteins, rendering it useless
|
|
|
which nitrogenous bases are double ringed structures? singled ringed structures?
|
A and G = double rings (purines)
T and C = single rings (pyridines) |
|
|
how many HB bonds between A and T? C and G?
|
2 btwn A and T
3 btwn G and C |
|
|
what is a single chromosome consist of?
|
one DNA double helix wrapped aroud histone proteins forming chromatin
|
|
|
how is okazaki fragments linked?
|
DNA ligase
|
|
|
where is rRNA made?
|
nucleolus
|
|
|
what enzyme adds on nucleotides off the template strand of DNA to make mRNA?
|
RNA polymerase
|
|
|
what is purpose of poly A tail?
|
prevent degradation of RNA molecule
|
|
|
what's the coding regions of DNA? non-coding regions of DNA?
|
coding region = exons
non-coding regions - introns |
|
|
where does RNA splicing occur?
|
nucleus
|
|
|
how many possible codons are there?
how many aa's are there? |
64 - possible codons
20 -aa's |
|
|
what are the two RNA binding sites inside the ribosome?
|
peptidyl site, aminoacyl site
|
|
|
which site in ribosome does the first tRNA enter?
|
P site of ribosome
|
|
|
how does tRNA "stick" to mRNA?
|
hydrogen bond between anticodon on tRNA and codon on mRNA
|
|
|
what's the first aa?
|
methionine
|
|
|
what enzyme forms a peptide bond between the two amino acisd in the P and A sites?
|
peptidyl transferase
|
|
|
what are 3 stop codons?
|
UGA, UAG, UAA
|
|
|
when does translation stop?
|
when a stop codon enters the A site
|
|
|
what is a missense mutation?
|
replacement of one aa
|
|
|
cells have yet to differentiate
|
stem cells
|
|
|
when does differentation happen?
|
early in development - irreversible
|
|
|
what's the mechanism behind txn regulation?
|
coiling of chromosome to physically prevent or allow the access of txn factors and RNA polymerase to the promoter regions of DNA
|
|
|
what's the mechanism behind post-txn regulation?
|
mRNA splicing
control over the rate at which mRNA leaves the nucleus via nuclear pores |
|
|
mechanism behind tln regulation
|
lifespan of mRNA (dp on the length of the poly-A tail added during RNA modification in the nucleus)
|
|
|
mutation causing production of alleles that produce faulty version of the enzymes needed for metabolism
|
inborn errors of metabolism
|
|
|
what is mendel's law of segregation?
|
1) for every given trait, an individual inherits two alleles for the trait
2) as an individual produces egg and sperm, the two alleles segregate so that each gamete contains only a single allele per trait. exception - allele on male sex chromosome - male contain only one X, will not have two alleles per trait for genes on sex chromosome |
|
|
true or false: dominant trait is more common or more advntageous than recessive?
|
false
|
|
|
breeding between P generation involving one trait
|
monohybrid cross
|
|
|
determining the genotype of a parent with a dominant phenotype by crossing with a homozygous recessive mate
|
test cross
|
|
|
law of independent assortment
|
1) alleles must assort independently during gamete formation - distribution of alleles for one trait has no influence on the distribution of alleles for other trait
2) if two genes are linked (occur on same chromosome) they will not assort independently, and thus will be inherited together, changing the expected outcomes in the offspring |
|
|
cross involving two unlinked traits
|
dihybrid cross
|
|
|
location of a gene on a chromosome
|
locus
|
|
|
genes that occur on the same chromosome
|
linked
|
|
|
predict outcomes:
1) alleles are close together 2) loci of the alles are far away from each other |
1) possibly inherited together
2) possibility for crossing over or genetic recombination to occur |
|
|
all genotypes in the population
|
gene pool
|
|
|
both alleles being expressed, leading to intermediate phenotype
|
incomplete dominance
|
|
|
both alleles being dominant - expression of both phenotypes
|
codominant - human blood types
|
|
|
mroe than one gene acting to influence a single trait
|
polygenic trait - skin colora nd hair color
result - continuous variation |
|
|
one gene interferes with the expression of another gene, lead to masking of an expected trait
|
epistasis
|
|
|
single gene influencing two or more other traits
|
pleiotrophy - ex. sickle cell disease (reduced oxygen ability of hemoglobin protein --> affect multiple organ systems in the body)
|
|
|
why is colorblindness and hemophilia more common in males
|
recessive sex-linked
|
|
|
measure of the frequency with which a trait is actually expressed in the population (environmental influence on gene)
|
penetrance
|
|
|
measure of extent of expression of a phenotype (environmental influence on gene)
|
expressivity
|
|
|
growth and replacement of cells
|
mitosis
|
|
|
where does mitosis not occur?
|
gametes, mature human nerve cells, muscle cells
|
|
|
stage in mitosis: parent cell is growing larger, add cytoplasm, replicate organelles
|
G1
|
|
|
DNA synthesis, the chromosomes are all replicated, two sister chromatids connected at centromere
|
S
|
|
|
cell continues to grow in size, make final preparation for cell division
|
G2
|
|
|
phase where mitosis and cytokinesis occur
|
M
|
|
|
three phases of cell cycle G1, S, G2
|
interphase - preparing for cell division
|
|
|
mature human nerve and muscle cells are in this phase - cells loes the ability to progress through the cell cycle, don't divide, cell cycle where division will never resume
|
G0
|
|
|
where do spindle fibers that radiate out (asters) of centrioles attach to?
|
kinetochore
|
|
|
chromosome condensation, breakdown of nuclear membrane, centrioles replicate and move to hte oposite side, spindle fibers are produced
|
prophase
|
|
|
centromere split, separation of sister chromatids
|
anaphase
|
|
|
spindle apparatus disappear, new nuclear membrane forms, chromosome uncoil back to original state, cytokinesis
|
telophase
|
|
|
structure of two replicated chromosomes twisting together in synapsis
|
tetrad
|
|
|
what's separation of homologous pairs?
|
disjunction
|
|
|
gameotogenesis in male vs. female
|
male - all four gametes become functional sperms
female - only one becomes a functional egg (3 --> polar bodies) |
|
|
chromosome fail to separate properly during meiosis
|
nondisjunction
|
|
|
cause of downsyndrome
|
nondisjunction in female gamete, receiving extra chromosome --> trisomy
|
|
|
what is monosomy
|
when a gamete is missing a chromosome as a result of nondisjunction - embryo with 45 chromosomes
|
