Sexual Reproduction + Meiosis

Question 1

What does meiosis result in?

Answer 1

haploid gametes

Question 2

How is ploidy restored in haploid gametes?

Answer 2

through fertilization

Question 3

What makes up a homologous chromosome?

Answer 3

one maternal chromosome and one paternal chromosome

Question 4

What makes a cell diploid?

Answer 4

it has two copies of the same information

one from mom and one from dad

Question 5

What are the two steps of sexual reproduction?

Answer 5

Meiosis

Fertilization

Question 6

Parthenogenesis

Answer 6

animals can produce eggs that develop into offspring without fertilization

ex: insects, reptiles, and fish

Question 7

What is the choice between asexual and sexual reproduction determined by?

Answer 7

Enviornmental factors that cause natural selection

Question 8

Fragmentation

Answer 8

type of asexual reproduction

each fragment grows into a full individual

ex: fungi, sea stars, worms

Question 9

Cloning

Answer 9

individuals contain a trait that can produce viable offspring

this leads to the offspring already being pregnant as well because they contain the trait

Question 10

Who did a lot of work regarding sexual reproduction?

Answer 10

John Maynard Smith

Question 11

What does asexual reproduction facilitate?

Answer 11

exponential growth

can produce more offspring than with sexual reproduction

Question 12

Why do asexual species tend to die out?

Answer 12

there is not as much genetic variation to survive catosphroic events

asexual species often do not give rise to new species because there is not enough diversity (end lineage)

Question 13

Disadvantages of sex

Answer 13

very costly to males (dangerous and uses resources)

Question 14

How does sexual reproduction lead to greater genetic variation?

Answer 14

independent assortment

crossing over

random combinations of egg and sperm

Question 15

Physiological strategies for sexual reproduction

Answer 15

external fertilization

internal fertilization

Question 16

karyotype

Answer 16

the number and types of chromosomes present in an organism

Question 17

How many chromosomes are in a human cell?

Answer 17

46

we have 23 unique chromosomes and our cells are diploid, so we have 2 copies of each

Question 18

How many autosomes do humans have?

Answer 18

22

Question 19

autosome

Answer 19

non-sex chromosome

Question 20

ploidy number

Answer 20

how many copies

ex: humans ploidy number = 2

Question 21

Where does the meiosis reduction division occur?

Answer 21

Meiosis I

Question 22

Prophase I

Answer 22

homologous chromosomes go from random distribution to distinct pairing

crossing over occurs

Question 23

Metaphase I

Answer 23

homologous chromosomes independently assort to the middle of the cell in 2 columns

Question 24

Independent assortment

Answer 24

chromosomes can line up in different orders

Question 25

Crossing over

Answer 25

homologous chromosomes are linked together in synapsis (bivalent formation)

when they start to partially separate a chiasmata forms

this is where crossing over takes place