lecture 16

Question 1

germ-line cells give rise to

Answer 1

germ cells (special reproductive cells that carry a copy of the genome to progeny)

Question 2

somatic cells

Answer 2

all other cells

Question 3

only mutations in – cells are passed on to offspring

Answer 3

germ-line cells

mutations in somatic cells are not

Question 4

point mutations are

Answer 4

changes that affect a single nucleotide pair

Question 5

neutral mutation

Answer 5

no effect on gene

Question 6

what happens if point mutations occur in regulatory DNA

Answer 6

the gene expression will be affected

Question 7

gene duplications

Answer 7

promote the emergence of new genes

Question 8

gene duplication and divergence

Answer 8

mutation in one copy will be tolerable as long as the other copy still functions

Question 9

homologous recombination can cause

Answer 9

gene duplication

• unequal crossing over= one long chromosome w gene duplication and one short chromosome

Question 10

when do whole genome duplications occur?

Answer 10

occurs when cell division doesn’t happen after genome duplication

Question 11

exon shuffling

Answer 11

exons encode for independent protein domains

duplication/movement of exons so that they are found in new genes give rise to new proteins

Question 12

a mobile genetic element is

Answer 12

a DNA sequence that can move from one location in a chromosome to another

Question 13

what can a mobile genetic element do?

Answer 13

can disrupt a gene if inserted somewhere important (coding sequence, regulatory DNA)

can make new genes by fusing the existing gene and the mobile genetic element

Question 14

horizontal gene transfer

Answer 14

transfer of DNA from one organism to another

Question 15

vertical gene transfer

Answer 15

transfer of DNA from parent to progeny

Question 16

homologous genes have

Answer 16

similar sequences due to common ancestry
- common proteins are found between species

Question 17

phylogenetic tree compares

Answer 17

nucleotide changes between species

Question 18

genetic changes and selection

Answer 18

changes that benefit survival will be passed on

changes that have no consequence might be passed on

changes that are harmful will not be passed on

Question 19

mutations would be found in

Answer 19

areas of DNA that DO NOT encode for a product/regulate a product

Question 20

why would mutations be found in areas of DNA that do not encode for a product?

Answer 20

genes that encode for products are essential.

mutations would affect ability to reproduce.

essential genes are highly conserved (kept the same!!)

Question 21

noncoding/regulatory sequences are less likely to

Answer 21

stay the same.

therefore more likely to have mutations

Question 22

conserved synteny

Answer 22

preservation of gene order and location in the genome of different species

-ex. mouse and human beta-globin genes occur in the same order and location

Question 23

purifying selection

Answer 23

individuals w mutations that impair important functions have been eliminated

Question 24

vertebrate genomes size

Answer 24

all vertebrate genomes have roughly the same number of genes but the overall size varies A LOT

Question 25

compare fugu genome and human genome

Answer 25

Fugu genome is 1/10 the size of human genome bc of smaller introns

but the position of introns and exons are still the same between species

Question 26

why is rRNA used to show evolutionary relationships between species? (tree of life)

Answer 26

rRNA is essential for translation

rRNA should be HIGHLY conserved.
this makes it easy to compare between organisms