DNA

Question 1

Describe the structure of DNA

Answer 1

Sugar phosphate back bone with complementary bases joined by hydrogen bonds

Question 2

What type of bond joins the deoxyribose sugar to the phosphate group

Answer 2

Covalent

Question 3

What way does DNA spiral

Answer 3

Clockwise (right - handed)

Question 4

What does antiparallel strands mean

Answer 4

Strands line up 5’ to 3’ and 3’ to 5’

Question 5

What are the complementary base pairs

Answer 5

Adenine and Thymine

Cytosine and Guanine

Question 6

Which two bases are purine

Answer 6

Guanine and Adenine

2 H bonds

Question 7

Which two bases are pyrimidine

Answer 7

Thymine and Cytosine (think Y)

3 H bonds

Question 8

Which is the leading strand of DNA

Answer 8

5’ to 3’

Question 9

Describe the process of DNA replication

Answer 9

1. DNA molecule unzips as H bonds break between base pairs
2. Primer must be present at 3’ end
3. Enzyme DNA polymerase adds nucleotides to the template DNA strand in a replication fork (replication strand)
4. Leading strand of DNA replicated
5. On lagging strands, okazaki fragments are formed and are regulated discontinuously
6. DNA ligase joins fragments together
7. 2 new identical double helix formed

Question 10

Why is DNA replication a semi-conservative process

Answer 10

Contains one new strand and one original strand

Question 11

What enzymes are involved in DNA replication

Answer 11

DNA polymerase to add nucleotides

DNA ligase joins together okazaki fragments

Question 12

What are the names of the fragments from the lagging strand

Answer 12

Okazaki

Question 13

List the stages in mitosis

Answer 13

Prophase
Metaphase
Anaphase
Telophase
Cytokinesis

Question 14

Describe Prophase

Answer 14

chromosomes condense
nuclear membranes dissapear
Spindle fibres form from the centriole

Question 15

Describe Metaphase

Answer 15

chromosomes alligned at equator of the cell
Attatched by fibre to each centriole
*Max concentration of chromosome *

Question 16

Describe Anaphase

Answer 16

sister chromatids separate at centromere (longitudinally)

Move to opposite ends of cell (move back)

Question 17

Describe telophase

Answer 17

new nuclear membranes form

Each cell contains 46 chromosomes (diploid)

Question 18

describe cytokinesis

Answer 18

Cytoplasm separates

2 new daughter cells

Question 19

Are germ cells haploid or diploid

Answer 19

haploid

Question 20

Who do you inherit mitochondrial DNA from

Answer 20

Mother via egg

Question 21

What is meiosis

Answer 21

Cell division in germline cells

Question 22

How many sperm are produced from a mitosis

Answer 22

4

Question 23

Describe the coding regions of DNA

Answer 23

Introns - cut out after alternate splicing

Exons - essential

Question 24

Where does alternate splicing occur

Answer 24

Nucleus - not cytoplasm

Question 25

What are the 3 types of RNA

Answer 25

mRNA, tRNA, rRNA

Question 26

Describe mRNA

Answer 26

Transcribed from DNA

Carries info for protein synthesis

Question 27

Describe tRNA

Answer 27

Translates mRNA sequence into amino acid sequence

Adapter molecule between coded amino acid and mRNA

Question 28

Describe rRNA

Answer 28

Component of ribosomes

Transported to cytoplasm to combine with proteins to form a ribosome

Question 29

Where is rRNA formed

Answer 29

The nucleus

Question 30

What starts and stops mRNA translation

Answer 30

Start codons and stop codons

Question 31

What happens in mRNA translation

Answer 31

mRNA sequence is converted into an amino acid sequence

Question 32

Describe the process of mRNA translation

Answer 32

As mRNA slides through the ribosome tRNA binds to complementary bases, adding its amino acid load to the polypeptide chain by strong peptide bonds

Question 33

Where does mRNA translation occur

Answer 33

Ribosome