Unit 5 - Heredity

Question 1

Gametes

Answer 1

• a sex cell ( sperm or an egg)
• designated by the n number

Question 2

What are gametes made by?

Answer 2

meiosis

Question 3

Gametogenesis

Answer 3

the process in which cells undergo meiosis to make sex cells

Question 4

Haploid Number

Answer 4

n - number of chromosomes

Question 5

Oocyte

Answer 5

egg cell

Question 6

Fertilization

Answer 6

• sperm and egg meet (sperm enters egg)
• restores the diploid number (2n) bc two haploid gametes each containing half the number of chromosomes (the haploid number), combine to form a diploid.

Question 7

Diploid

Answer 7

• a number of chromosomes in in a body cell
• 2n

Question 8

Body cells

Answer 8

somatic cells - autosomes

Question 9

autosomes

Answer 9

are the chromosomes that determine traits other than sex (e.g., eye color, height, metabolism).

Question 10

Somatic Cells

Answer 10

are all the cells in your body except gametes (sperm and egg cells).

Question 11

Karyotype

Answer 11

picture of the chromosomes

Question 12

Homologous Chromosomes

Answer 12

separate chromosomes (NOT DUPLICATED CHROMOSOMES) that code for the same type of genes (ex. height )
- inherited

Question 13

Mitosis

Answer 13

produces 2 genetically identical cells

Question 14

Meiosis

Answer 14

produces gametes ( provides variety )

Question 15

Interphase (part of S-phase)

Answer 15

• start with 6 chromosomes and duplicate the chromosomes
• in the end we should have 4 haploid cells with half chromosomes in each so 3 in each

Question 16

Meiosis 1 ( the first division )
Prophase 1

Answer 16

• chromosomes condense
• homologous chromosomes pair up (one from dad and one from mom)
• recombination of genes (when they pair up they combine to make tetrad and chiasma

Question 16

Synapsis in Prophase 1

Answer 16

when the homologous chromosomes pair up (one from dad and one from mom)

Question 17

Tetrad in Prophase 1

Answer 17

is created when two homologous chromosomes (one from each parent) pair up.
Each chromosome in the pair has two identical sister chromatids. Together, that makes 4 chromatids total, hence the name “tetrad.”

Question 18

Chiasma

Answer 18

physical site where homologous chromosomes overlap and swap DNA. So this is where they are touching and where they recombine to get that variety

Question 19

Meiosis 1
Metaphase 1

Answer 19

the homologous chromosomes line up

Question 20

Law Of Independent Assortment

Answer 20

chromosomes can line up in many different arrangements

Question 20

Meiosis 1
Anaphase 1

Answer 20

• homologous chromosomes separate
• if chromosomes don’t separate correctly then you have non-disjunction which is uneven distribution of chromosomes

Question 20

Meiosis 1
Telophase 1

Answer 20

two haploid cells are made and they are genetically different

Question 20

Why do the chromosomes go straight to prophase and not to interphase when you go to meiosis 2?

Answer 20

After Meiosis I, the sister chromatids are already present, so there’s no need to replicate the DNA again before Meiosis II.

Question 20

Meiosis 2
Prophase 2

Answer 20

nuclear envelope breaks down

Question 21

Meiosis 2
Metaphase 2

Answer 21

chromosomes line up

Question 21

Meiosis 2
Anaphase 2

Answer 21

the sister chromatids pull apart

Question 22

Meiosis 2
Telophase and Cytokinesis

Answer 22

both cells divide again, making four unique haploid cells.
and now we make sex cells so 4x sperm, 1x egg, and 3x polar bodies that are useless

Question 23

polar bodies

Answer 23

small non-usable cells that do not fertilize and they get reabsorbed into the body

Question 24

Law Of Segregation

Answer 24

genes that go into gametes sort randomly and this allows for variety