DNA + Genetics

Question 1

Chargaff’s Rule

Answer 1

Guanine must go with Cytosine
Adenine must go with Thymine

Question 2

DNA Structure

Answer 2

Nucleotide ladder
- Sides - Sugar-phosphate
- Rungs - Base pairs

Question 3

Why is replication semi-conservative?

Answer 3

half of the original strand is used for the new one

Question 4

What sugars are in DNA?

Answer 4

Deoxyribose sugars

Question 5

Sugars in RnA?

Answer 5

Ribose Sugars

Question 6

What bases does RNA have?

Answer 6

Cytosine, Guanine, Adenine and Uracil

Question 7

DNA Replication

Answer 7

process of copying DNA

Question 8

What is Klinefelter’s Syndrome?

Answer 8

genetic disease in human males
- small testes, wide hips and breast development
- Y chromosome isn’t fully developed
- extra X chromosome

Question 9

Name given to gene abnormalities?

Answer 9

Mutation

Question 10

What is a mutation?

Answer 10

• errors and changes in DNA, genes or chromosomes
• can result in various consequences
  e.g: Polydactyly (more digits) is due to a DNA mutation

Question 11

Spontaneous mutation

Answer 11

cause cannot be identified

Question 12

Induced mutation

Answer 12

cause can be identified

Question 13

Mutagen/mutagenic agent

Answer 13

factor that triggers mutations
- radiation
- chemical substances
- infectious agents

Question 14

Point mutations

Answer 14

can occasionally occur in DNA replication, resulting in incorrectly paired bases, deletion or insertion of a nucleotide.

Question 15

Genotype

Answer 15

a pair of alleles that influence the appearance of a trait. e.g: Aa, Bb

Question 16

Phenotype

Answer 16

the collection of traits observed in an organism. e.g: brown hair, blue eyes

Question 17

Incomplete Dominance

Answer 17

both alleles are expressed equally
e.g: snapdragon; FRFW = Pink

Question 18

Codominance

Answer 18

The heterozygote shows both traits at the same time
e.g: CRCW = Red and White

Question 19

Pure Breeding

Answer 19

Same allele for a particular trait or characteristic
parents of an offspring both have the same homozygous genotypes

Question 20

Recessive

Answer 20

an allele for a particular trait that only appears if there are two (hh, ii)
represented by a lowercase letter

Question 21

Dominant

Answer 21

an allele for a particular trait that can appear even if there is only one
represented by a capital letter (HH, Hh)

Question 22

Sex-Linked

Answer 22

a condition passed to the offspring on the X chromosome, recessive
e.g: XhY = affected male
XHXH = unaffected female
XHXh = unaffected (carrier)

Question 23

Male chromosomes

Answer 23

XY

Question 24

Female chromsomes

Answer 24

XX

Question 25

How is the offspring's gender determined?

Answer 25

- one from father (X or Y) - one from mother (X)