exam 2 ch 8

Question 1

Bdelloid rotifers reproduce ?

Answer 1

without sex

Question 2

Daughters are ______ of their mother

Answer 2

clones

Question 3

Reproduction from unfertilized eggs, Requires chromosome changes before or during meiosis

Answer 3

Parthenogenesis

Question 4

When a cell exits the mitotic cell cycle in G2 phase and undergoes multiple S phases without entering mitosis and undergoing cytokinesis

Answer 4

Premeiotic endoreplication

Question 5

2 methods of parthenogenesis

Answer 5

Premeiotic endoreplication
fusion of egg and polar body

Question 6

During Meiosis instead of being degraded, the polar bodies add their DNA to the egg

Answer 6

fusion of egg and polar body

Question 7

Asexual reproduction that requires the presence of sperm without the actual contribution of its DNA for completion

• Paternal DNA is destroyed before fusion.
  -Males, do not pass on their DNA

Answer 7

gynogenesis

Question 8

2 methods of Gynogenesis

Answer 8

1. ameiosis
2. premeiotic endoreplication

Question 9

Suppression of one of the meiotic division

Answer 9

ameiosis

Question 10

premeiotic endoreplication

Answer 10

Is a type of gynogenesis

Question 11

The opposite of gynogenesis is

Answer 11

Androgenesis

Question 12

Elimination of the female genome after fertilization.

Answer 12

Androgenesis

Question 13

-Evolutionary advantageous to individual male (normally only gives ½ of chromosomes).
-It is deleterious to the population as a whole.
-Egg-producing individuals become rare & the population can decline to extinction.
-Seen in some insects, trees, clams.

Answer 13

androgenesis

Question 14

Ejection of the chromosomes from one parent before an endoreplication phase before meiosis or ameiosis.

Answer 14

Hemiclonal Reproduction

Question 15

why is sexual reproduction used by 99% of eukaryotes?

Answer 15

Searching for a mate takes time and energy.
-Increases risk of being eaten by a predator.
-Once found, a potential mate may demand additional exertion or investment before agreeing to cooperate.
-Sex itself may expose the parties to sexually transmitted diseases.
-And for all that, the mating may prove to be infertile

Question 16

So asexual reproduction is?

Answer 16

1. Faster.
2. More energy efficient.
3. Only requires one parent

Question 17

In the absence of recombination, an accumulation of irreversible deleterious mutations occurs (Because everyone inherits the same alleles)

Answer 17

mulers ratchet

Question 18

Reduction in the mean fitness of a population due to the presence of deleterious alleles

Answer 18

genetic load

Question 19

Frequently the most lethal thing for most lifeforms is?

Answer 19

infection

Question 20

Surface proteins on immune cells (antigen-presenting B cells and T cells) and enable the immune system to recognize pathogens

Answer 20

Major histocompatibility complex (MHC)

Question 21

the non-random association of alleles at adjacent loci

Answer 21

linkage disequilibrium

Question 22

Over time, a pair points on a chromosome in the population move from linkage __________ to
linkage ____________, as recombination events eventually occur between___________________________________

Answer 22

disequilibrium, equilibrium; every possible point on
the chromosome

Question 23

Genotypes at one locus are randomly distributed with respect to genotypes at
another locus

Answer 23

linkage equilibrium

Question 24

set of DNA variants along a single chromosome that tend to be inherited together
- Recombinations between these variants are rare

Answer 24

haplotype

Question 25

can increase linkage disequilibrium in a population

Answer 25

natural selection and drift

Question 26

is the main mechanism that reduces disequlibroum in a population

Answer 26

sexual reproduction

Question 27

Variations of nucleotides at a specific loci in the genome

Answer 27

Single Nucleotide Polymorphisms (SNPs)

Question 28

Natural selection and drift can _________ linkage disequilibrium in a population
Sexual reproduction is the main mechanism that __________ it

Answer 28

increase, reduces