Chapter 9 Pt. 1 - Mitosis

Question 1

Why do cells divide?

Answer 1

To replace normal wear, tear, and senescence.

Question 2

What are some stem cell sources?

Answer 2

In embryos and some adults. In Vitro fertilization from human embryonic stem cells. Induced pluripotent stem cells.

Question 3

What are induced pluripotent stem cells?

Answer 3

Specialized adult cells that can be reprogrammed to another function.

Question 4

What are permanently differentiated cells?

Answer 4

Cells such as liver and brain cells that do not divide to repair.

Question 5

What is the rule of dividing cells?

Answer 5

Cells will only divide into more cells like them. Liver cells will only divide into more liver cells.

Question 6

What is the Prokaryotic Cell Cycle?

Answer 6

Chromosome attaches to cell membrane.
DNA in a singular, circular membrane replicates.
Two chromosomes separate and move a part.
New membrane added.
Cleavage in between.
Two new daughter cells.

Question 7

What is the Chromosome Organization in Eukaryotic Cells?

Answer 7

Folded, spiraled, and compacted to fit within a nucleus.

Question 8

What is a Gene?

Answer 8

Lengths of DNA that code for a trait.

Question 9

What is a Locus?

Answer 9

The geographical location on the chromosome of a gene.

Question 10

What is a Telomere?

Answer 10

The “end” signal for a chromosome; located at each end.

Question 11

What is a Centromere?

Answer 11

Chromosome movement; located in the center.

Question 12

What is a Duplicated Chromosome?

Answer 12

Chromosome DNA is replicated (copied).

Question 13

What are Sister Chromatids?

Answer 13

Two identical DNA helices attached at the centromeres.

Question 14

What are Homologues?

Answer 14

Chromosomes that contain the same genes (not necessarily the exact DNA)

Question 15

How many Homologue pairs do humans have?

Answer 15

23 = 46 Chromosomes

Question 16

What is a Diploid?

Answer 16

Somatic cells that have pairs of homologous chromosomes. (2n)

Question 17

What are the two sex chromosome pairings in humans?

Answer 17

XX for female. XY for male.

Question 18

What is a Haploid?

Answer 18

Half or only one type of each chromosome. (1n)

Question 19

Where are some Haploids located?

Answer 19

Gametes (sperm and egg) have 1 copy of each pair of chromosomes.

Question 20

When does fertilization take place?

Answer 20

When 1n + 1n = 2n (Haploids become Diploids)

Question 21

What is the set up of human chromosomes?

Answer 21

One gamete each of 22 chromosomes. Either an X or Y chromosome.

Question 22

What is the process of cell division in Eukaryotic Cells?

Answer 22

Mitosis.

Question 23

What is the first stage of Mitosis?

Answer 23

Interphase

Question 24

What is the Interphase of Mitosis?

Answer 24

Acquires nutrients, grows and differentiates, prepares for division.

Question 25

What is the second phase of Mitosis?

Answer 25

Prophase

Question 26

What is included in Interphase?

Answer 26

Growth and Differentiation, Growth and Division Prep, and DNA Synthesis.

Question 27

What is the Prophase?

Answer 27

The chromosomes condense and a spindle forms. The nucleolus disappears and nuclear membrane dissolves. Kinetochore holds the chromosomes to the spindle.

Question 28

What is the third phase of Mitosis?

Answer 28

Metaphase

Question 29

What is the Kinetochore?

Answer 29

What holds the chromosomes to the spindle.

Question 30

What is the Metaphase?

Answer 30

Kinetochores line up on equator. Nuclear Membrane still dissolved.

Question 31

What is the Anaphase?

Answer 31

Sister Chromatids separate and move to poles.

Question 32

What is the Telophase?

Answer 32

Chromosomes decondense. Nuclear envelope starts to re-form. Spindle disappears.

Question 33

What is Cytokinesis?

Answer 33

Microfilaments contracts. Each "daughter" cell has 1 nucleus and half of the cytoplasm. Back to Interphase.

Question 34

What is the purpose of Mitosis?

Answer 34

Make more cells for several different reasons.

Question 35

Where does Mitosis occur?

Answer 35

Everything but in gamete-producing organs.

Question 36

How many Chromosomes are in humans?

Answer 36

23 Homologous pairs; 46 total chromosomes. 23 from Mom; 23 from Dad.

Question 37

What is Meiosis?

Answer 37

To reduce the genetic complement in half to ensure restoration of the correct number of chromosomes upon union of two sex cells.

Question 38

How many chromosomes are in a sperm or egg?

Answer 38

23

Question 39

What is the third phase of Mitosis?

Answer 39

Metaphase

Question 40

What is the fourth phase of Mitosis?

Answer 40

Anaphase

Question 41

What is the fifth phase of Mitosis?

Answer 41

Telophase

Question 42

What is the final phase of Mitosis?

Answer 42

Cytokinesis