Exam 1 Lecs - 2

Question 1

Mitochondria and chloroplast also have …

- mito inherited … –> can trace back history of … through …

Answer 1

DNA;
maternally;
females;
mito DNA

Question 2

Skin - …
Oxygen - …
eyes sensitive to light due to pigment proteins like …

Answer 2

keratin;
Hb;
rhodopsin

Question 3

variants of proteins … and … species

Answer 3

within;

between

Question 4

variants of proteins within and between species:

- within species = … –> necessary to have … in a population, source of …

Answer 4

polymorphism;
selection;
variation

Question 5

polymorphisms aren’t necessarily for … - two or more possibilities of a … on a …

Answer 5

proteins;
trait;
gene

Question 6

… possible triplets of nucleotides

human genome about … bases long in a single strand –> only about …% of this actually codes for genes

Answer 6

64;
3 giga;
5

Question 7

Human genome about 3 giga bases long in a single strand. Only about 5% of this actually codes for genes.
More drastic differences in other species –> salamander genomes are about … times larger than human genome, most of which is …

Answer 7

20;

non coding

Question 8

… mutation is when we’re coding for the same aa, even with the mutation
… mutation and … mutation change aa

Answer 8

synonymous;

transversion; transition

Question 9

… rates can be measured:
can calculate … of one occurring in a nucleotide - that’s basically the average rate
helps us determine how long ago we … with other organisms

Answer 9

mutation;
probability;
shared common ancestors

Question 10

homozygous parent + hetero parent
Mendelian ratio: …, …

If both parents hetero:
… dominant, … hetero, … recessive

Answer 10

50; 50;

25; 50; 25

Question 11

since chromosomes separate …, just … their probabilities to determine the probability of a … occurring

Answer 11

independently;
multiply their probabilities;
specific genotype

Question 12

… = linked genes can … freely, so then you have the same probabilities as if they were on …

Answer 12

free recombination;
recombine;
different chromosomes

Question 13

linked genes …

Darwin’s theory would probably not work if there was a … mechanism of heredity

Answer 13

decrease variation;

non-Mendelian blending

Question 14

excess fecundity results in …

Answer 14

competition

Question 15

natural selection has 4 conditions:

• …
• …
• variation in …
• variation in … of organisms according to the state they have for a …

Answer 15

reproduction;
heredity;
individual characters;
fitness; heritable character

Question 16

fitness references likelihood to …

Answer 16

reproduce

Question 17

HIV:
… virus in a … membrane
has an enzyme called …

Answer 17

RNA;
lipid;
reverse transcriptase

Question 18

HIV has reverse transcriptase:

• uses this to replicate itself within a …
• target for development of drug - …, a molecule similar to …

Answer 18

host cell;
3TC;
cytosine

Question 19

HIV target for development of drug - 3TC

• if reverse transcriptase uses 3TC rather than C during replication, … and the virus can’t …
• 3TC inhibits … of the virus

Answer 19

HIV replication stops;
multiply in the body;
reproduction

Question 20

HIV target for development of drug - 3TC:
initially HIV population decreases but then within 3 days, … HIV strains are found in the body
-all … strains selected against and … strains start increasing in frequency until it reaches … of viral population in patient’s virus

Answer 20

3TC-resistant;
non-resistant;
resistant;
100%

Question 21

HIV target for development of drug - 3TC:

• Initially HIV pop decreases but then within 3 days, 3TC-resistant HIV strains are found in the body. All non-resistant strains selected against and resistant strains start increasing in frequency until it reaches 100% of viral population in patient’s virus
• Example of evolution of … by ….
• the resistant strain has a mutation in … The resistant version has …, so only adaptive for HIV in … -> … when drug is absent

Answer 21

drug resistance; 
natural selection; 
one codon; 
slower reproduction; 
presence of drug; 
disadvantage

Question 22

Natural selection can be …, …, or …

Answer 22

directional;
stabilizing;
disrupting

Question 23

Natural selection can be directional, stabilizing, or disrupting:

• directional favors …
• stabilizing favors …
• disrupting selects against …, favors …

Answer 23

one extreme;
average;
average;
both extremes

Question 24

Natural selection can be directional, stabilizing, or disrupting:

• disrupting selects against average, favors both extremes: with enough time, disruptive selection leads to the …
• if there’s no selection, fitness graph will be a … bc all individuals have …

Answer 24

evolution of two species;
straight line;
the same fitness

Question 25

when selecting for size, also selecting for …

at a morphological level, individuals of a natural population … for almost any character we may measure;

Answer 25

growth rate;

vary

Question 26

At a morphological level, individuals of a natural population vary for almost any character we may measure:

• … variation /… (e.g. …)
• … variation

Answer 26

continuous; continuous character;
body size;
categorical

Question 27

variation also at … level (e.g. different forms of …)
variation at … level (e.g. …)
variation also at … level (all variation derives from this)

Answer 27

cellular; 
chromosome; 
biochemical; 
protein polymorphism; 
DNA;

Question 28

variation generated by … and …

Answer 28

mutation;

recombination

Question 29

variation generated by mutation and recombination:

• natural selection can only operate on … in the population
• this process is … with respect to the direction of adaptation
• direction of evolution is uncoupled from direction of …

Answer 29

available variation;
random;
variation

Question 30

variation generated by mutation and recombination:

- when a new recombinant/mutant genotype arises, there is no tendency for it to arise in the direction of …

Answer 30

improved adaptation