1-Human genetics

Question 1

chromosome

Answer 1

long strings of genetic material known as deoxyribonucleic acid (DNA)

Question 2

DNA:

Answer 2

helix-shaped molecule made up of nucleotide base pairs, make up genes that control/partially control a number of visible characteristics, known as traits

Question 3

allele

Answer 3

specific version of a gene

Question 4

homozygous

Answer 4

when someone has two copies of the same allele

Question 5

heterozygous

Answer 5

when someone has a combination of alleles for a single gene

Question 6

polygenic

Answer 6

traits that are controlled by more than one gene

Question 7

gene mutations:

Answer 7

sudden, permanent change in a gene, can provide a source of harmful genes, but can also give the individual an advantage over those who do not have the mutation

Question 8

GENES

Answer 8

DNA sequence that controls physical characteristics

Question 9

chromatin

Answer 9

uncoiled chromosomes, Dna-protein complex

Question 10

histones

Answer 10

proteins that DNA wraps around to create chromatin

Question 11

genotype

Answer 11

• actual genetic code!!
• inherited!
• cannot change!

Question 12

PHENOTYPE

Answer 12

• physical characteristics
• one’s genes and environment can change this!!

Question 13

sickle-cell anemia

Answer 13

genetic condition in which red blood cells, which are normally round, take on a crescent-like shape

• many people with this die at an early age
  
  • but… survival of the fittest didn’t make it less common!
  • still common among people of African descent
• why? being a carrier gives immunity from malaria, but full-blown sickle-cell anemia does not

Question 14

range of reaction theory

Answer 14

our genes set limits on a given characteristic
our environment determines to which degree our genes are expressed!!

Question 15

Gene-environment correlation:

Answer 15

genes determine which environments we are likely to gravitate towards
our environment determines to which degree our genes are expressed

Question 16

Epigenetic effects

Answer 16

Environmental stressors and behaviours can “turn on” dormant genes

• looks beyond genotype itself and studies how the same genotype can be expressed in different ways
• how the same genotype can lead to different phenotypes
• gene expression is often influenced by environmental context in ways that are not entirely obvious!!

Question 17

cortisol and its impact on our phenotypes

Answer 17

produced when experiencing acute stress) can make it so the “do not read” genes are read