Slide Set 2 Flashcards Preview

Mammalian Physiology > Slide Set 2 > Flashcards

Flashcards in Slide Set 2 Deck (45)
Loading flashcards...
1

Proteins

- enzymes
- transport proteins
- form structural skeleton
- specific & variable
- structure encoded in dna

2

The 2 stages of protein synthesis

1. Transcription (DNA-RNA)
2. Translation (RNA-protein)

3

Genes are tightly coiled with histones, what removed the histone revealing promoter segment?

enzymes

4

Transcription

- forms messenger RNA
- mRNA transports DNA from nucleus OUT to cytosol

5

Translation

mRNA (in cytoplasm) > ribosome > tRNA transfers amino acids to mRNA (anticodon) > peptide bonds are joined

6

1. T A C C C T C A A
2. A U G G G A G U U
3. U A C C C U C A A
4. met gly val

1. template strand
2. mRNA strand (U replaced T)
3. tRNA strand (U replaced T)
4. Amino acid strand

7

molecular genetics

study of how genes are turned on and off and how they affect phenotype

8

Real DNA hero

Rosalind Franklin, not Watson & Crick

9

Where is chromatin

In nucleus (part of supercoiled region of chromosome)

10

Nucleosome

- DNA + Histone proteins (H2A/H2B/H3/H4)
- repeat to make chromatin

11

Genes are on or off in
- euchromatin
- heterochromatin

- ON
- OFF

12

__ copies DNA sequence to produce mRNA

DNA POLYMERASE

13

DNA helicase :
RNA polymerase :
RNA nucleotides (Uracil instead of Thymine)

- unwinds DNA
- binds and recognises start site
- base pair with DNA
=mRNA chain is formed

14

In case of protein coding DNA, transcription is the beginning of the process that ultimately leads to _ of the genetic code (via the _ intermediate) into a function _ or _.

translation
mRNA
peptide
protein

15

Promoter regions

- DNA sequences
- define where beginning of transcription begins
- are upstream or at the 5' end of the transcription initiation site

16

What binds to promoter regions?

TRANSCRIPTION FACTORS and RNA POLYMERASE, they initiate transcription

17

Direction of transcription

5'----3' (coding strand)
3'----5'
DNA is antiparallel

18

CREM

cAMP response element modulator
is a transcription factor
binds to CRE in promoter region

19

What doesn't occur in absence of CREM?

spermiogenesis

20

What are the 2 types of transcription factors

- gene-specific transcription factor (activate specific genes)
ex: estrogen receptor
- general transcription factor (activate all genes)

21

What are the 2 types of transcription factors

- gene-specific transcription factor (activate specific genes)
ex: estrogen receptor
- general transcription factor (activate all genes)

22

Alternative splicing

= method of processing mRNA
- enzymes clip out segment of mRNA (the introns)

23

Introns vs Exons

Introns : noncoding segments
Exons : genes that encode protein, express

24

Site of transcription

nucleus

25

Site of translation

cytoplasm

26

What are epigenetic mechanisms affected by?

Development
Environmental chemicals
Drugs, pharmaceuticals
Aging
DIet

27

What is an epigenetic factor found in some dietary sources?

methyl group
it can activate or repress genes

28

epigenetics

is the study of heritable phenotype changes that do not involve alterations in the DNA sequence

29

housekeeping genes

genes always expressed in cells

30

Looking for proteins by Western blot

CREM runs at 34Kda