6.1 Cellular Control (genes/ Mutations)

Question 1

What are the two types of mutation called? Describe?
P,I

Answer 1

• Point Mutation- ONE base pair replaces another.
• Indel Mutation- ONE or MORE nucleotides are inserted or deleted for the length of DNA. Causing a FRAMESHIFT.

Question 2

What are the 3 types of point mutation?

Answer 2

Silent
Missense
Nonsense

Question 3

What is silent mutation?
Why is this mutation possible with an exception?

Answer 3

•base triplets can change but still code for the same amino acid.
•possible because there is multiple triplet codes that code for the same amino acid. Except- methionine.

Question 4

What is the advantages of slient mutation (point mutations)? (Why is it not bad)

Answer 4

•ADV: The primary, secondary and tertiary structure is not altered.

Question 5

What’s the difference between structural gene and regulatory genes?
Give an example for both

Answer 5

Structural genes are not involved in gene regulation however regulatory genes are
-Structural genes: lac Z & lac Y
-Regulatory geans: repressor protein

Question 6

In eukaryotic cells for gene expression, what does it involve?
H M

Answer 6

Histone modification

Question 7

During cell division, what is DNA wrapped tightly around? During p
What does it prevent in terms of expression? (Gene activation/ inactivation)

Answer 7

Histones during prophase

Prevents gene expression making gene inactive

Question 8

In eukaryotic cells during gene expression what can we use loosen chromatin? 2

What does it do? + in order to?

Answer 8

Acylation or phosphorylation

Decreases the positive charge of hisstone to loosen chromatin

Question 9

What can be used to change the loosely wrapped chromatin from interphase back to cell division? M

What does this product do? H

Answer 9

Methylation

This increases the hydrophobic nature of histones and condenses the chromatin and histones making them tightly wrapped.

Question 10

Where does in prokaryotic gene expression the repressor and RNA polymerase bind to? On gene?

What do these do?

Answer 10

RNA polymerase: To P ( promoter)
- transcribes structural genes

Repressor: lac O
- Prevents RNA polymerase from binding to promoter region

Question 11

What is the difference between primary mRNA and mRNA?

Answer 11

Primary mRNA contains Intron and exons

mRNA is after the removal of Introns by joining exons

Question 12

In signalling when a molecule bind to a receptor on membrane it activates G protein to activate adenyl cyclase What does this convert?

Answer 12

ATP to cAMP

Question 13

What does cAMP ACTIVATE?

this activated molecule philosophises enzymes what does it do to ATP?

Answer 13

Hydrolyses ATP to ADP
May also phosphor realise CREB protein that enters the nucleus and act as a transcription factor

Question 14

What is a homeotic gene?
Master .. direct development of…

Answer 14

Masterregulator gene that directs the development of particular body the segments

Question 15

What is one type of homeontic gene?

What does it regulate and in what 3 domains does it do it in?

Answer 15

Homebox sequence

Regulating anatomical development in animals, fungi, and bacteria

Question 16

What is a subsets of homebox sequence? H

What does this gene do in terms of anatomical features? Bp from? H T

Answer 16

Hox genes

Anatomical features in correct location on body plan head to tail

Question 17

Apoptosis is programmed cell death when the DNA break into fragments?

Answer 17

Before- prostrations called blabs form
After- Cell breaks into vesicles and is ingested by phagocytic cells

Question 18

Apoptosis is programmed cell death when the DNA break into fragments?

Answer 18

Before- prostrations called blabs form
After- Cell breaks into vesicles and is ingested by phagocytic cells