6.1 - cellular control

Question 1

mutation

Answer 1

change in dna base sequence caused by mutagens

Question 2

types of mutations

Answer 2

• point (sub)
• indel - insertion/deletion

Question 3

point mutation

Answer 3

affects only 1 base
3 types - silence, missense, nonsense
could have no effect - dna code is degenerate

Question 4

whats a frameshift mutation

Answer 4

occurs in indel mutation
disrupts triplet code reading

Question 5

what effect can a mutation have

Answer 5

• neutral/silent - no effect (degenerate code)
• beneficial - enhanced function of protein
• damaging - malfunctioning protein made

Question 6

nonsense mutation

Answer 6

codon has changed into a stop codon

Question 7

missense

Answer 7

change to triplet code which alters amino acid sequence

Question 8

transcription factors

Answer 8

**proteins which can bind to different base sequences on dna and initiate transcription of genes

HAS TO ENTER NUCLEUS AND BIND TO DNA TO WORK

Question 9

OPERON

Answer 9

group of simultaneously controlled genes that are either all expressed or not

Question 10

what is a lac operon

Answer 10

found in e coli.
aid lactose digestion

Question 11

lactose induces the production of….

Answer 11

Question 12

what does the lac operon look like

Answer 12

Question 13

IF LACTOSE IS PRESENT

Answer 13

Question 14

LACTOSE ISNT PRESENT

Answer 14

Question 15

HOW IS CYCLIC AMP USED

Answer 15

INCREASES RATE OF TRanscription of lac operon

Activate proteins inside the cell at the post translational level by altering 3-D structure

Question 16

introns

Answer 16

non coding regions of dna

Question 17

exons

Answer 17

coding regions of dna

Question 18

post transcriptional level

Answer 18

intond are removed from primary mRNA by splicing
Exons join together form mature mRNA strands
Mature mRNA leaves the nucleus for translation

Question 19

homeobox genes

Answer 19

sequences of genes which create proteins that regulate expression of other genes involved in the formation of embryo

Question 20

hox genes

Answer 20

responsible for correct body development and positioing of body parts

only animals9

Question 21

How do hox genes control development?

Answer 21

homeobox sequences code for a part of the protein called homeodomain

Domain binds to specific DNA enabling the protein to work as a transcription factor

Proteins bind to DNA at the start of developmental genes activating/ repressing transcription

alters The production of proteins involved in the development of the body plan

Question 22

how is apoptosis and mitosis involved in the development of body plans?

Answer 22

Mitosis and differentiation create the body parts and then apoptosis refines by removing the unwanted structures TOES