bio exam 4

Question 1

Darwin’s Heredity Theory

Answer 1

Little “Bits” (gemmules) of each trait aggregated in the gamete to form an offspring

Question 2

The Blending Hypothesis

Answer 2

Traits from each parent mixed together and the offspring is a perfect mix of he 2 parents

Question 3

Gregor Mendel

Answer 3

monk
mathematician
pea plants
enginerr

Question 4

Monohybrid Cross

Answer 4

Crossbreeding two organisms in reference to a specific trait

Question 5

True Breeding

Answer 5

Only produces 1 of the 2 traits possible over many generations

Question 6

Mendel established

Answer 6

the dominant and recessive relationship between traits

Question 7

Genotype

Answer 7

what gene you are carrying :
AA- Homozygous Dom
Aa- Heterozygous
aa- Homozygous recessive

Question 8

Phenotype

Answer 8

The physical manifestation of the genotype

Question 9

Incomplete Dominance

Answer 9

The dominant allele determines how much of a gene you have. If mom is white and dad is red, then Aa could show up as pink

Question 10

Co-Dominance

Answer 10

When two or more dominant alleles are present in one trait Ex: AB blood type

Question 11

Pleiotropy

Answer 11

One gene at one locus WITH IT’S OWN INDEPENDENT PHENOTYPE, affects the expression of another gene at another locus

Question 12

Epistasis

Answer 12

One gene at one locus WITHOUT IT’S OWN INDEPENDENT PHENOTYPE, affects the expression of another gene

Question 13

Y chromosome:

Answer 13

• has 75 genes on it
• All about sexual reproduction and secondary sexual characteristics

Question 14

X chromosome:

Answer 14

• has 1000 genes
• MOST are about sexual reproduction and secondary sexual characteristics
• SOME sex linked genes are not about sexual reproduction and secondary sexual characteristics

Question 15

Some recessive disorders are sex-linked:

Answer 15

Men are more likely to show sex-linked recessive disease because they only have 1 X chromosome and must show whatever that chromosome carries

Question 16

Carriers must be heterozygous, so what is the only gender that can be a carrier

Answer 16

women

Question 17

X-inactivation

Answer 17

In the Autosomal/non-sex/somatic cells. one X is randomly activated.

Question 18

Mosaicism

Answer 18

Each cell displays traits on only one X

Question 19

Klinefelter’s

Answer 19

XXY ( extra X from mom = nondisjunction)

Question 20

Polygenic

Answer 20

Many genes affect one characteristic

Question 21

if A = 10% then….

Answer 21

T= 10%
C= 40%
G= 40%

Question 22

Origin:

Answer 22

Where the enzymes respawn for duplication bind at the chromosome

Question 23

At the origin,

Answer 23

• 2 strands are separated, forming the replication bubble

Question 24

The ends of the replication bubble are called

Answer 24

Forks

Question 25

Replication proceeds away from:

Answer 25

the origin into the forks in both directions.

Question 26

When 2 bubbles meet they….

Answer 26

form together

Question 27

When replication is complete,

Answer 27

the 2 daughter DNA mols each consist of an old strand and a new strand

Question 28

What are the 7 enzymes in replication/duplacation

Answer 28

Helicase, Topoisomerase, Single stranded binding proteins, Primase, DNA polymerase 3, DNA Polymerase 1, and Ligase

Question 29

Helicase:

Answer 29

• breaks hydrogen bonds
• unwinds the helix (creates a knot in the DNA)
• unzips the double strand

Question 30

Topoisomerase

Answer 30

• relieves tension from helicase
• Cuts off the knot and heals the cut

Question 31

Single Stranded Binding Proteins

Answer 31

• follows helicase and prevents the 2 strands from rezipping

Question 32

Primase

Answer 32

initiates replication by building a short RNA primer at the origin

Question 33

DNA polymerase 3

Answer 33

• builds the new complementary DNA strands by adding to the primers
• Can only build from 5’ to 3’

Question 34

Leading strand

Answer 34

• Runs from 5’ to 3’
• quick and easy to build
  -runs into the replication fork

Question 35

Lagging strand

Answer 35

• Runs from 3’ to 5’ into rep fork
• Difficult to build
• Primase builds multiple primers along the lagging strand
• DNA poly 3 fills in between the primers in the opposite direction

Question 36

Okazaki Fragments

Answer 36

The short segments of DNA between the primers on the lagging strand

Question 37

DNA Polymerase 1

Answer 37

• Removes RNA nucleotides and replaces them with DNA nucleotides

Question 38

Ligase

Answer 38

• Follows DNA poly 1 to check that DNA’s polymerase nucleotides