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Flashcards in Storing and Using Genetic Information Deck (68)
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1

What is a phenotype?

Physical manifestation of genotype

2

What is a genotype?

All of the genes in our DNA, even the ones that are not expressed

3

Why are proteins functionally different?

Due to their different structures

4

What does the structure of a protein depend on?

The primary structure (sequence of amino acids)

5

What is DNA?

A chain of nucleotide monomers that contains all of our genetic information

6

What does each nucleotide contain?

Sugar

Base

Phosphate group

7

What structure does DNA form?

Double helix

8

How many bases is there per turn of the helix?

10

9

How do polypeptide chains of DNA run to each other?

Antiparralel to one another

10

How are the groves in DNA described?

Major and minor groves which is important for the interaction of proteins

11

What is the pairing of bases called?

Compliment base pairing

12

What bases pair with what in DNA?

Thymine paires with adenine

Guanine pairs with cytosine

13

What does compliment base pairing happen?

Due to the structures of the bases:

Thymine pairs with ademine due to both forming 2 hydrogen bonds

Guanine pairs with cytosine due to both forming 3 hydrogen bonds

14

What bases form 3 hydrogen bonds with each other?

Cytosine and guanine

15

What bases form 2 hydrogen bonds with each other?

Thymine and adenine

16

What is the site of a cells genetic information (DNA)?

Nucleus

17

Where does the first step of protein production take place and what is this?

DNA replicaiton which takes place in the nucleus

18

What does each nucleus contain?

A nucleolus which can take up to 25% of its volume and is where transciption and assemble of rRNA takes place

19

Where does transcription and assemble of rRNA take place?

Nucleolus

20

What is DNA packaged into?

Thread like structures called chromosomes

21

When are chromosomes visible?

During cell division

22

What is a chromosome?

Single piece of DNA containing many genes, regulatory elements and other nucleotide sequences

23

How many chromosomes does a human have?

46

24

What can the structure of chromosomes be described as?

Highly ordered to contain vast amounts of DNA

25

What is the process of packaging chromosomes?

1) Chromatin is the double stranded helical structure of DNA

2) DNA is packed with histones to form nucleosomes, with each consiting of 8 histones

3) Binded with H1 histone to form chromatosome

4) Folded up and tightly coiled to produce fibre called chromatid of the chromosome

26

What is chromatin?

Mixture of DNA, proteins and RNA thay packages DNA within the nucleus

27

What are the 2 forms of chromatin?

Heterochromatin (condensed)

Euchromatin (extended)

28

What must the chromatin do for transcription and replication to occur?

Open up to allow enzymes to access the DNA template

29

What are the 2 mechanisms for opening up chromatin to allow replication or transcription to occur?

Histones can be enzymatically modified

Histones can be displaced by chromatin remodelling complexes

30

What should be noted about both processes of opening up chromatin?

They are reversible