exam 4 part 2

Question 1

anagenesis

Answer 1

evolution within a lineage over time

Question 2

cladogenesis

Answer 2

splitting of one lineage into two

Question 3

what is used to evaluate evolutionary divergence

Answer 3

DNA sequences

Question 4

paralogs

Answer 4

homologous sequences found in the same species and arrive through gene duplication

Question 5

orthologs

Answer 5

homologous sequences found in different species

Question 6

highest mutation rates are observed where?

Answer 6

regions of the genome that have the least effect on function
- the more substitutions the less it effects

Question 7

outgroup

Answer 7

an OTU that is known to have diverged earlier than all the others

Question 8

terminal node

Answer 8

the last node in the branch that doesn’t have any child nodes

Question 9

internal nodes

Answer 9

any node that has atleast 1 child node

Question 10

cancer is — but rarely —

Answer 10

genetic, heritable

Question 11

G1/S checkpoint

Answer 11

monitors for proper cell size and undamaged DNA

Question 12

G2/M checkpoint

Answer 12

holds up cycle until replication and DNA repair are complete

Question 13

M checkpoint

Answer 13

proper spindle formation and attachment

Question 14

tumor

Answer 14

distinct mass of abnormal cells that do not have normal controls on cell division

Question 15

benign

Answer 15

abnormal cells remain localized and do not invade surrounding tissue

Question 16

malignant

Answer 16

cancer cells invade surrounding tissue

Question 17

metastic

Answer 17

cancer cells spread and establish secondary tumors in other sites in the body

Question 18

genetic causes of cancer

Answer 18

• mutations in somatic cells
• single defective gene
• polygenic (more that one defective gene)
• chromosome aberration
• viruses

Question 19

environmental influences on cancer can …

Answer 19

cause mutations and alter gene expression

Question 20

most cancers are …

Answer 20

sporadic and influenced by the environment

Question 21

cancers develop …

Answer 21

over time

Question 22

mutations leading to cancer usually result from

Answer 22

errors in replication

Question 23

tumor suppressor gene function

Answer 23

prevent bad cells from dividing

Question 24

proto-oncogenes

Answer 24

allow good cells to divide
- must be activated to be regulated properly

Question 25

to lose cell cycle regulation what must happen

Answer 25

must disrupt both copies of the gene - recessive action

Question 26

knudson two hit hypothesis

Answer 26

both copies have to be defective in same cell to allow tumor to develop

Question 27

tumor suppressor genes

Answer 27

- RB - p53 - BRCA1

Question 28

RB suppressor gene

Answer 28

Knudson two hit hypothesis - normal protein responsible for regulating G1/S checkpoint

Question 29

BRCA1/2 suppressor gene

Answer 29

causes breast cancer - normally used to repair double strand breaks

Question 30

p53 suppressor gene

Answer 30

functions at G1 checkpoint - if p53 isnt working right, cell division occurs even through DNA is damaged

Question 31

difference in proto-oncogenes and tumor suppressor genes

Answer 31

proto-oncogene only need mutation in 1 copy (dominant) while tumor suppressor needs both (recessive)

Question 32

oncogenes

Answer 32

normal function: transcription factor abnormal function causes reciprocal translocation leading to cancer

Question 33

retroviruses can cause cancer by

Answer 33

- causing mutations and rearrangement of proto-oncogenes - insert a strong promoter near proto-oncogenes

Question 34

telomere length affect on cancer

Answer 34

telomeres usually shorten as a cell ages, but in cancer cells there is more telomerase expression causing "immortality"

Question 35

angiogenesis

Answer 35

growth of new blood vessels