Genetics and Epigenetics

Question 1

What are Proteins?

Answer 1

Proteins are chains of amino acids, there are over 20 different amino acids to choose from and the specific combination changes the function and structure of the protein

Question 2

What are the different types of proteins and what do they do?

Answer 2

Structural: help hold cells and tissues together (eg. collagen)
Enzymes: catalyze chemical reactions and aid in metabolism
cell signalling: Peptide neurotransmitters, receptors for hormones, neurotransmitters, and cytokines

Question 3

What is DNA?

Answer 3

Deoxyribonucleic acid (DNA) is a simple chain of molecules that can be made up of 4 nucleotide bases.

Question 4

Where is DNA stored?

Answer 4

DNA is stored in chromosomes in. the cells nucleus. Humans have 23 pairs of chromosomes and receive on pair from each parent.

Question 5

What are the 4 nucleotide bases that build DNA?

Answer 5

Adenine (A)
Thymine (T)
Guanine (G)
Cytosine (C)

A goes with T, and G goes with C

Question 6

What are Genes?

Answer 6

Genes are segments of DNA that code for particular proteins

Question 7

What does the copying of DNA allow for?

Answer 7

Cell division and reproduction

Question 8

How do genes code for proteins?

Answer 8

Genes are organized into codons and each codon is 3 neuclotides long, and they ‘code’ for a specific amino acid

Question 9

How many codons are there?

Answer 9

There are 43 codons (a total of 64) but a lot are redundant

Question 10

What are the 4 steps of gene expression?

Answer 10

1. DNA particle unravels showing gene that is to be transcribed
2. Strand of mRNA is transcribed from exposed DNA and carried genetic code from nucleus into cytoplasm
3. In cytoplasm the mRNA strand attached itself to a ribosome which moves along the strand translating each codon into the the appropriate amino acid
4. When ribosome reaches end of mRNA a codon instructs it to release the completed protein

Question 11

What is Optogenetics?

Answer 11

It is a transgenic technique that combines genetics and light to control targeted cells in living tissue, based on the discovery that light can activate proteins

Question 12

How does optogenetics work?

Answer 12

Fibre optic light is delivered to selective brain regions such that all neurons exposed to the light respond immediately

Question 13

What is Epigenetics

Answer 13

It is the study of changes in gene expression related to experience

Question 14

What are some experiential factors in gene expression changing?

Answer 14

Chronic stress, traumatic events, disease, drugs, culture

Question 15

What are the difference between genetic mutations and epigenetic changes?

Answer 15

Genetic mutations alter meaning, epigenetic changes alter activity

Question 16

What are histones?

Answer 16

DNA wrapped around clusters of protein

Question 17

What is chromatin and what do they do?

Answer 17

Chromatin is a combination of DNA and protein in chromosomes, they help regulate the behaviour of genes by keeping them in an inactive state

Question 18

What are epigenetic changes usually caused by?

Answer 18

Physical changes in the structure of the chromatin

Question 19

What is histone acetylation?

Answer 19

an epigenetic mark that loosens/relaxes the chromatin and increases gene transcription

Question 20

What is histone methylation?

Answer 20

an epigenetic mark that tightens /condenses the chromatic and decreases gene expression

Question 21

What is the role of environment in Genetics?

Answer 21

It can influence gene activity by regulating the behaviour of epigenetic writers and erasers

Question 22

What can help the brain respond and adapt to environment?

Answer 22

The addition/removal or acetyl and methyl groups.