Final Review Flashcards
breathing
exchange of gases
cellular respiration
aerobic harvesting of energy in food molecules
chemical equation of cellular respiration
C6H12O6 + O2 → ATP + H2O + CO2
stages of cellular respiration
glycosis
citric acid cycle / krebs cycle
oxidative phosphorylation
reactants, products, and location of glycosis
glucose
2 ATP, 2 pyruvate
cytoplasm
reactants, products, and location of citric acid cycle
2 pyruvate
2 ATP, NADH, CO2, and FADH2
mitochondrial matrix
reactants, products, and location of oxidative phosphorylation
electrons shuttled by NADH and FADH2
32 ATP
inner membrane of the mitochondria
redox reaction
oxidation- loss of H atoms and electrons
reduction- gain of H atoms and electrons
substrate level phosphorylation
enzyme transfers a phosphate group from a substrate directly to an ADP, creating an ATP
steps within oxidative phosphorylation
electron transport chain
chemiosmosis
where does the ETC take place and why is it beneficiall?
cristae(folds) of the inner mitchondrial membrane increases surface area, allowing for many copies of the ETC
where do the electrons go in the ETC?
they leave NADH and FADH2 and move through proteins in the membrane
oxygen is the final electron accepter and H2O is produced as a result
energy released from the e- movement is used to actively transport H+ across the membrane
Describe the H+ gradient across the inner mitochondrial membrane
H+ ions move from the matrix to the inner mitochondrial membrane
how does ATP synthase use the H+ gradient
as H+ ions are being transported, the rotation of the enzyme activated the synthase of ADP and a phosphate group
Describe what happens to cellular respiration when agents (such as cyanine, carbon monoxide, rotenone) disrupt this process.
they disrupt cellular respiration by blocking the ETC
anaerobic respiration
creating energy in the absence of oxygen
obligate anaerobes
requires anaerobic conditions and are poisoned by oxygen
facultative anaerobes
can make ATP either by fermentation or oxidative phosphorylation
products of lactic acid fermentation
lactic acid
products of alcohol fermentation
ethanol and CO2
where does photosynthesis occur in a leaf
chloroplasts
parts and functions of a chlorplast
stroma - dark reactions/Calvin Cycle
grana (stacks of thylakoids) - light reactions
reactants of photosynthesis and where do they come from?
CO2 and H2O from the atmosphere
products of photosynthesis
O2
C6H12O6 (glucose)
H2O
2 stages of photosynthesis
light reactions
dark reactions/calvin cycle
what molecules link the two stages of photosynthesis?
ATP and NADPH
what happens when a photon is absorbed by a pigment?
one of the pigment’s electrons jump to an energy level further away from the nucleus, and enters an “excited” state
reactants of the light reactions and where they come from
photons of light energy from the sun
what is an abbreviation for a photosystem and which one comes first
PS2 then PS1
what is the difference btw PS2 and PS1?
photons are absorbed by chlorophyll in PS2, exciting an e-
e- flows to PS1 by the ETC and another photon is absorbed in PS1, exciting an e-, which is picked up by NADP+, reducing it to NADPH
e- boosted by PS2 are passed through the ATP mill and boosted again by PS1, to reduce NADP+ to NADPH
products of the light reactions
ATP and NADPH
how are the products of the light reactions created?
ATP synthase combines ADP with a phosphate group through a proton moving down the concentration gradient
NADP+ becomes NADPH through reduction
where do the dark reactions occur
stroma
reactants of the dark reactions and where they come from
ATP and NADPH from the light reactions
what is RuBP
starting material in the calvin cycle
5 carbon sugar
ribulose biphosphate
always in the dark reactions
how is rubisco involved in the dark reactions?
it is an enzyme that aides in CO2 fixation
What happens to 3-PGA during the dark reactions
ATP gives it a phosphate group, making it ADP
NADPH adds a phosphate and gives H&electrons, making it NADP+
becomes G3P
How many G3P are created during the dark reactions and where do they end up
6 G3P are created
1 goes to create glucose
other 5 are rearranged to create RuBP
asexual reproduction
1 parent, identical offspring/DNA
sexual reproduction
2 parents, varied offspring/DNA
why does cell division occur in unicellular organisms?
to reproduce an entire organism
why does cell division occur in multicellular organisms?
growth, development, repair
chromatin
DNA and proteins, makes chromosomes
chromosome
structure that contains most of the organism’s DNA, composed of chromatin and 2 chromatids
centromere
location where 2 sister chromatids join together
chromatid
contains identical copies of DNA molecule
stages of cell cycle and what happens in each one
interphase - period of cell growth (G1 and G2) and DNA synthesis (S)
mitotic phase - mitosis and cytokinesis
anchorage dependency
cells must be in contact w a solid surface in order to divide
density dependent inhibition
when crowded cells stop dividing
why are cancer cells different from normal cells?
they don’t need a solid surface in order to divide
they don’t stop dividing once cells get crowded, forming tumors
how do chemotherapy drugs inhibit cancer cell growth
taxol freezes the mitotic spindle
vinblastin prevents the mitotic spindle from forming
mitosis
division of the nucleus
cytokinesis
division of the cytoplasm
stages of mitosis
prophase metaphase anaphase telophase look at diagram - be able to identify cells in various stages of mitosis
chromosomes become visible as paired chromatids and the nuclear envelope disappears
nuclear envelope disappears
spindles form
prophase
physical barrier that encloses the nucleus breaks down
prometaphase
homologous chromosomes line up along the metaphase plate
metaphase
homologous chromosomes separate from one another, as mitotic spindles shorten
sister chromatids split
anaphase
total split of homologous chromosomes to the poles and the separation into two new cells
mitosis is complete
nuclear envelope reforms
chromosomes spread out
telophase
how do plant and animal cells differ in cytokinesis
animals - cleavage furrow
plants - cell plate
homologous chromosomes
pairs of chromosomes that match in length, centromere position, and gene location
bacteriophage
virus that attacks bacteria
composed of DNA and protein
Why did Hershey & Chase use bacteriophage in their experiments?
it is only composed of DNA and protein, which were the two molecules in contention for the genetic molecule
conclusion of hershey and chase experiment
DNA is the hereditary molecule
monomers of DNA and RNA
nucleotides
parts of a nucleotide
sugar
phosphate
nitrogenous base
nitrogenous bases
adenine
cytosine
guanine
thymine
categories of bases
purine: adenine, guanine - two rings
pyrimidine: cytosine, thymine - one ring
chargoff’s rule (which bases pair with which)
purines have to pair w pyrimidines
a - t
g - c
similarities and differences in DNA and RNA
RNA - single strand, AUCG, ribose
DNA - double strand/double helix, ATCG, deoxyribose
central dogma of biology
DNA is transcribed into RNA
RNA is translated into proteins
where does transcription take place
nucleus
role of RNA polymerase
to link together the growing chain of RNA nucleotides during transcription, using a DNA strand as a template
role of the promoter
starting site of transcription
role of the terminator
stop site of transcription
where does translation take place
cytoplasm
what languages are being translated
nucleotide language is translated into amino acid language
form and function of tRNA
tRNA has a specific amino acid attached to it, along with an anticodon
its function is to bring amino acids into the ribosome, where proteins are constructed
initiation stage of translation
mRNA binds to a small ribosomal subunit, and the first tRNA binds to the mRNA at the start codon
the large ribosomal subunit joins the small subunit, allowing the ribosome to function
elongation stage of translation
codon recognition: next tRNA binds to the mRNA at the A site
peptide bond formation: joining of the new amino acid to the chain
translocation: tRNA is released from the P site and the ribosome moves tRNA from the A to the P site
termination stage of translation
completed polypeptide is released
ribosomal subunits separate
mRNA is released and can be translated again
gene
factor that is passed down from parent to offspring
allele
one of a number of different forms of a gene
genotype
genetic makeup of an organism
phenotype
characteristics of an organism
