Genome Structure

Question 1

DNA Outline

Answer 1

Info storage molecule, found in nucleus (eukaryotic) and cytoplasm (prokaryotic). Instructions for protein production quantity, location and timing

Question 2

Autosomal Chromosome Outline

Answer 2

22 pairs of chromosomes, that code for non-sex characteristics

Question 3

Sex Chromosome Outline

Answer 3

A pair of chromosomes that code for sex characteristics

Question 4

Bond between A and T nucleotides

Answer 4

Double H bond

Question 5

Bond Between C and G

Answer 5

Triple H bond. Most stable nucleotide bond

Question 6

Gene Def

Answer 6

Length of DNA that directs the synthesis of a protein

Question 7

Nucleotide structure

Answer 7

Sugar, phosphate and nitrogen base

Question 8

Chemistry of DNA Helix backbone

Answer 8

Sugar + Phosphate. Hydrophilic and negatively charged. Created overall negative charge of DNA

Question 9

Chemistry of DNA Helix base pairs

Answer 9

Nucleotides. Hydrophobic (internal to avoid nucleus’s fluid based enviornment)

Question 10

DNA Structure; Grooves Outline

Answer 10

The twists of a DNA helix, vary in size (big-smal-big-small). 2 types; major (big twist, typically site easiest to edit from) and minor (small). Binding proteins are selective based on groove size

Question 11

Why are 3’ and 5’ Cs important on sugars

Answer 11

Both contain hydroxyl (OH) groups. Used to link nucleotides together

Question 12

How is Deoxyribose Different To Ribose

Answer 12

D: 2’ C contains H. R: 2’ C contains OH

Question 13

Watson-Crick Bond Outline

Answer 13

H bond between complementary nucleotides. Weakest bonds in DNA structure

Question 14

Phosphodiester Bonds Outline

Answer 14

Covalent bond between sugar on 3’C on 1 nucleotide and phosphate on 5’C on another. Strongest bonds of DNA (helix backbone)

Question 15

Base Stacking Bonding Outline

Answer 15

Van der Wall interaction between base pairs stacked ontop of eachother. Intermediate force between phosphoditerase and Watson-Crick

Question 16

Why is the 3’ end more reactive then the 5’

Answer 16

5’ contains a phosphate (more stable) while 3’ contains a hydroxyl group (more reactive).

Question 17

Nucleosome Outline

Answer 17

DNA (- charged) wrapped around a Histone (8 positively charged proteins)

Question 18

30nm Fibre Outline

Answer 18

Nucleosomes wrap in a coil around eachother to form a fibre that’s 30nm long

Question 19

DNA at Interphase

Answer 19

Chromatin, DNA chromosomes as threads

Question 20

DNA at Mitosis

Answer 20

Increasingly more condensed. Chromosomes become a distinct shape

Question 21

Euchromatin Outline

Answer 21

Weaker binds to histones, more gene expression. less condensed, easily transcribable. Has light G bands (takes up little Giemsa dye)

Question 22

Heterochromatin Outline

Answer 22

Stronger binds to histone, less gene expression. More condensed, harder to transcribe. Has dark G bands (takes up more Giemsa dye)

Question 23

p notation in chromosome structure

Answer 23

shorter chromosome arm

Question 24

q notation in chromosome structure

Answer 24

longer chromosome arm

Question 25

Centromeres Outline

Answer 25

Links sister chromatids together during cell division. Characterised by repetitive DNA

Question 26

Telomeres Outline

Answer 26

Non-coding DNA at chromosome top + bottom. Protescts coding DNA from degradation

Question 27

Somatic Cell Outline

Answer 27

Dipolid. 23 pairs of autosomal chromosomes and a apir of sex chromosomes

Question 28

Gamete Cells Outline

Answer 28

Haploid. 23 chromosomes and 1 sex chromosome

Question 29

Relationship between cell mutations, genetics and hereditry.

Answer 29

All cell mutations = genetic. somatic cell mutations aren't hereditery. Gametes cell mutations are. Not all genetic mutations are hereditry

Question 30

Chromatosome Outline

Answer 30

Nucleosome + H1 Histone

Question 31

Coding (/Conserved) DNA

Answer 31

5% of genome. Includes gene expression and regulation

Question 32

Non-coding (not conserved) DNA

Answer 32

95% of genome. Includes Transponenes (migrating DNA), microstaelites and repeat (structural) DNA. Evolves quickly across gnerations