Exam 4 Flashcards
Evolution
The change in allele or genotype frequencies over time.
When does evolution not happen
no selection, no genetic drift, no gene flow, no mutation, random mating
What is a molecular clock
a region of DNA or protein that has a known rate of accumulation of mutations over time
Natural selection occurs when
individuals with certain heritable phenotypes survive and reproduce better than others.
Stabilizing Selection
Average stays same, they move toward middle
Directional selection
Average moves in 1 direction, genetic diversity, become fixed
Disruptive Selection
Go against average. Average stays same but selects for extremes, does not pick average. Genetically diverse
Sexual Selection
Either fight for the women. Or will show off for the female
Artificial Selection
Human based, we chose what we want
Fitness
A measure of the extent to which an individual’s genotype is represented in the next generation
Synthesis of nucleic acids always occurs in the 5-3 direction. True or False
True
During transcription what direction is the DNA template “read” by the polymerase?
3 –> 5
Translation is the process by which?
proteins are synthesized from RNA molecules
How is the information stored in DNA
in the sequence of nucleotides
the strands in DNA molecules are
complemetary
why does ADP have less potential energy than ATP
because ADP has only two phosphate groups
how many steps are in glycolysis
10
in addition to ATP what are the end products of glycolysis
NADH and pyruvate
a cell undergoing mitosis in a small mamal conatins 8 homo pairs of chromosomes, how many are there at the end of G2
16
during anaphase 1 what separates
homologous chromosomes
the p53 gene __ the cell cycle
inhibits
Meiosis of one diploid cell results in the production of
4 haploid cells
enzyme and its function: DNA polymerase 3
proofread DNA base pairs
enzyme and its function: DNA ligase
synthesize Okazaki fragments
enzyme and its function: DNA helicase
unwind DNA
the mutation resulting in a change of one base pair of DNA so that a codon now codes for a different amino acid, its an example of
missense mutation
What are the 2 types of energy
Potential & kinetic
What is the relationship between strength of a covalent bond and the amount of chemical energy it contains?
The stronger the covalent bond, the less chemical energy it contains. The weaker the covalent bond, the more chemical energy it contains.
How does increasing the temperature affect the change in free energy (ΔG) of a chemical reaction?
Increasing the temperature increases the value of T∆S, which decreases ∆G, since ∆G = ∆H – T∆S. As a result, an increase in temperature makes it more likely that a reaction will proceed without a net input of energy.
How can the hydrolysis of ATP drive non-spontaneous reactions in a cell?
The hydrolysis of ATP releases energy. This energy can be used to drive nonspontaneous reactions in a cell if the total ΔG for the entire pathway is negative
What are three characteristics of enzymes
Enzymes reduce the activation energy of a chemical reaction, are catalysts, and are highly specific.
How does protein folding allow for enzyme specificity?
An enzyme will only act on those substrates that bind to its active site. Meaning an enzyme has to fold into its correct shape for the active site to be the right shape to bind its substrate.
What do enzymes change
Enzymes increase the reaction rate and decrease the activation energy.
How are the overall reactions for photosynthesis and cellular respiration similar and how are they different?
In photosynthesis, energy from sunlight is captured in chemical forms. In cellular respiration, carbohydrates are oxidized to CO2, releasing energy that is ultimately used to synthesize ATP.
What are the major inputs of the Calvin cycle?
CO2 (from the atmosphere) and ATP and NADPH (from the photosynthetic electron transport chain
What are the major outputs of the Calvin cycle?
ADP, NADP+, and carbohydrates (triose phosphates).
What are the four major stages of cellular respiration?
Glycolysis, Pyruvate oxidation, Citric acid cycle, and Oxidative phosphorylation
What are the two different ways in which ATP is generated in cellular respiration?
substrate-level phosphorylation and oxidative phosphorylation
What is the overall chemical equation for glycolysis?
Glucose + 2NAD + 2ADP + 2Pi → 2 pyruvate + 2ATP + 2NADH + 2H+ + 2H2O
How is a proton gradient used to generate ATP?
The protons accumulated in the intermembrane space cannot passively diffuse across the membrane, so they diffuse through a transport channel called ATP synthase.
How is cell division similar in prokaryotic cells and eukaryotic cells 1
one parent cell gives rise to two daughter cells, and the two daughter cells are genetically identical to each other and the parent cell, except for rare mutations
How is cell division different in prokaryotic cells and eukaryotic cells
(1) The size and shape of the genetic material; bacteria have a single circular chromosome, whereas eukaryotic cells have one or more linear chromosomes. (2) The DNA of prokaryotes is attached to the plasma membrane, allowing separation of DNA into the daughter cells by cell growth. In eukaryotic cells, the chromosomes are not attached to the cell or nuclear membrane.
What do you predict would be the consequence of a mutation in FtsZ that disrupts the function of the protein it encodes?
A mutation that disrupts the function of the FtsZ protein will block cell division
What are three situations in which mitotic cell division occurs?
in the development of multicellular organisms, maintenance and repair of organs and tissues, and asexual reproduction of unicellular eukaryotes
What are the five stages of mitosis?
Prophase, prometaphase, metaphase, anaphase, telophase
What are two ways in which the function of p53 can be disrupted?
by a mutation in the p53 gene or by an inhibitor and cancer, can inhibit the function of the p53 protein
What is the purpose of a testcross
to identify the genotype of an individual with the dominant phenotype.
