Unit 2

Question 1

Chromosomes

Answer 1

structure inside cell made of dna material and protein

Question 2

DNA

Answer 2

large organic molecule that stores the gentic code of the organism

Question 3

Gene

Answer 3

segment if dna that has information about specific protein that is related to certain trait

Question 4

Allele

Answer 4

form/version of a gene

Question 5

Diploid cell

Answer 5

(2n cell) cell that contaon 2 sets of chromosomes. In human all except gametes (sex cells) are diploid

Question 6

Haploid Cell

Answer 6

(n cell) cell contains one set of chromsomes (n=23)

Question 7

Homologous chromosomes

Answer 7

Homologous chromosomes are matched pairs containing the same genes in identical locations along their length (only applies to diploid)

Question 8

Gametes

Answer 8

sex cells- haploid

Question 9

Fertilization

Answer 9

Fusion of male and female gametes that form zygote

Question 10

Zygote

Answer 10

Fertilized egg (diploid)

Question 11

Meiosis process

Answer 11

1. homologous pair of chromosomes in diploid cell replicate
2. homologous pair of replicated chromosomes are in diploid cell
3. Homologous chromosomes split into haploid cell (w/ replicated chromosomes)
4. Sister chromosomes separate (w/o replicated chromosomes)

Question 12

Meiosis effect on genetic variation

Answer 12

• Crossing over (in prophase I)
• Random assortment of chromosomes (in metaphase I)

*Random fusion of gametes from different parents

Question 13

Principle of segrigation

Answer 13

genes exist in pairs that segregate randomly when gametes are formed (gamete has one copy of each gene, zygote has two)

Question 14

Principle of dominance

Answer 14

one version of gene will dominate the other (for ressesive to show must have 2 copies)

Question 15

Genotype

Answer 15

Combination of (Yy, YY, ect)

Question 16

Phenotype

Answer 16

resulting trait (eg: hair colour)

Question 17

Homozygous Dominant

Answer 17

2 dominant traits: XX

Question 18

Homozygous ressesive

Answer 18

2 recessive traits: xx

Question 19

Hetrozygous

Answer 19

1 dom and 1 recessive: Xx

Question 20

Pure breeding

Answer 20

population of Homozygous ressesive/dominant

Question 21

Hybrid

Answer 21

population of hetrozygous

Question 22

Testcross

Answer 22

cross between organism with dominant phenotype (unknown genotype) with one with recessive trait (homozygous recessive)

Question 23

Principle of independent assortment

Answer 23

Each pair of alleles separate independently. All possible combinations of factors can occur in the gametes in equal proportions. Occurs when genes are found on separate chromosomes or far a part on same one

Question 24

Co-dominance

Answer 24

both traits appear/both are dom

Question 25

Incomplete Dominance

Answer 25

blending of characteristics/neither are dominant

Question 26

Mitosis vs. meiosis

Answer 26

Mitosis: produces two genetically identical diploid cells (46 chromosomes still) Meiosis: produces 4 genetically different haploid cells (23 chromsomes)

Question 27

Hardy- Weinberg Equilibrium

Answer 27

allele frequencies and genotypes frequencies same from generation to generation (NO EVOLUTION) in the absence of 5 evolutionary conditions

Question 28

5 evolutionary conditions (can lead to micro evolution)

Answer 28

1. No mutations (no new alleles enter populations 2. No gene flow can occur (immigrations/emigrations) 3. Random mating must occur (individuals pair by chance) 4. Population must be large (no genetic drift) 5. No natural selection

Question 29

Mircro Evolution

Answer 29

change in allele frequencies that occurs over time within a population

Question 30

allopatric speciation + 3 steps

Answer 30

occurs when a species separates into two separate groups which are isolated from one another 1. geographical isolation 2. Microevolution 3. reproductive isolation

Question 31

reproductive isolation

Answer 31

nability of a species to breed successfully with related species due to geographical, behavioral, physiological, or genetic barriers or differences. - can be pre or post zygotic