Chapter 10

Question 1

Cellular Reproduction Overview

Answer 1

1. DNA replication - interphase
2. DNA separation - cell division, mitosis, reproduction at cell level, asexual reproduction, growth + development, repair and renewal
3. Cellular separation -cytokinesis
4. Daughter cells - identical DNA, all organelles

Question 2

Ploidy

Answer 2

Euk genetic material
number of unique chromosomes in a cell
N

Question 3

Chromosomes in humans

Answer 3

23 pairs, 46 total

Question 4

Homologous pairs

Answer 4

set of 2 chromosomes in a cell that are the same size and shape
contain genes in the same order
attached at centromere

Question 5

Somatic chromosomes

Answer 5

Euk genetic material
Diploid (2N)
any chromosomes excluding sex chromosomes
two copies
2N = 46

Question 6

Gametic chromosomes

Answer 6

Euk genetic material
Haploid (N)
one copy
N = 23
found in gamete (sex cell)

Question 7

Genome

Answer 7

double stranded DNA
linear
Euk genetic material

Question 8

Chromatin

Answer 8

Diffuse (invisible)
complex structure made of proteins that wrap around
form chromosomes in nucleus
uncondensed DNA
Euk genetic material

Question 9

Sister chromatids

Answer 9

parts following replication
identical copies of centrosomes connected at centromere
Euk genetic material

Question 10

Chromosomes

Answer 10

Condensed form of dna (visible)
Appear during prophase

Question 11

Centrosomes

Answer 11

animals only
microtubule organizing center
duplicated during interphase

Question 12

Centrioles

Answer 12

2 centrosomes
organelles involved with mitosis
origin of spindle fibers

Question 13

Kinetochore

Answer 13

Special proteins of centromere
attachment point of spindle fibers

Question 14

Spindle fibers

Answer 14

special microtubules; “mitotic spindles”
acquired from cytoskeleton
contraction pulls sister chromatids apart

Question 15

How long is one cell cycle

Answer 15

approx. 24 hrs (not all cells)

Question 16

Interphase

Answer 16

Mitotic stage
stage between successful division
cell mostly in this stage

Question 17

G0

Answer 17

holding stage
normal function
no preparation
repair DNA
90% of cycle
part of interphase

Question 18

G1

Answer 18

6 hrs
cell growth
“growth 1”
metabolic activity
Cell grows larger (2x organelles)
prepare for DNA synthesis

Question 19

S phase

Answer 19

12 hrs
doubling DNA
metabolic activity
DNA synthesis
sister chromatids; kinetochore
Centrosomes -> duplication begins
some organelles replication

Question 20

G2

Answer 20

5 hrs
“growth 2”
metabolic activity
prepare for mitosis
synthesize proteins (microtubule and spindle apparatus)
Centrosome 2x complete
(1 centrosome per pole)
finalize organelle replication
looks like normal cell, by the end centrosomes and chromosomes duplicated

Question 21

Mitotic stage

Answer 21

1 hr
mitosis
(prophase, metaphase, anaphase, telophase)
cytokinesis
division of nucleus, cytoplasm, organelles, DNA, left with 2 daughter cells

Question 22

Prophase

Answer 22

Beginning of mitosis
spindle fibers from centrosomes
Nuclear envelope dissolves
Nucleolus disappears
chromatin condenses (tightly packed chromosomes) visible
Visible as sister chromatids, bound together by centromere

Question 23

Asters

Answer 23

short spindle fibers
shaped like star

Question 24

Prometaphase

Answer 24

between prophase and metaphase
Nuclear envelop fragments, sister chromatids more condensed, kinetochore formed
spindle fibers invade nuclear area and centrosomes move toward poles

Question 25

Kinetochore spindle fibers

Answer 25

connect to sister chromatids and interact/ pull apart

Question 26

Non-kinetochore spindle fibers

Answer 26

connect the poles together and lengthen the cell

Question 27

Metaphase

Answer 27

centrosomes at opposite poles sister chromatids align according the centromeres metaphase plate is formed equidistant between poles spindle fibers from each pole connect to each pair of sisters, kinetochore to spindle fibers, pole connected to 1/2 of all chromatids

Question 28

Anaphase

Answer 28

Shortest stage sister chromatid cohesion proteins cleaves, chromatids separated each chromatid -> independent kinetochore spindle fibers begin to shorten and pull chromatids apart completely toward nonkinetochore fibers lengthen cell ends with each pole w same number of chromosomes

Question 29

Telophase

Answer 29

Daughter nuclei form, new nuclear envelop develops, nucleoli reappears chromosomes diffuse (non visible again) microtubules broken down mitosis is technically complete

Question 30

Cytokinesis

Answer 30

Separate process from mitosis separation of cytoplasm and PM cleavage furrow (animal) cell plate (plant) contractile ring draws tight and pinches apart(animal) golgi vesicles (plant) cell visibly splits

Question 31

Mitosis in plants

Answer 31

same steps but easier to identify same sequence no centrosomes yes spindle fibers cytokinesis cell plate ; builds a wall

Question 32

Prokaryotic cell division

Answer 32

Asexual reproduction 1 parent -> 2 offspring Binary fission 1. replication 2. elongation 3. chromosome pole migration 4. septum formation (PM pinches in) 5. 2 daughter cells produced

Question 33

Control of the cell cycle

Answer 33

Checkpoints; Go/No go system

Question 34

G1 control

Answer 34

most important go -> completes cell division no go -> enters G0

Question 35

G2 control

Answer 35

Go -> DNA not damaged no go -> DNA is damaged and goes to G0 to try to fix

Question 36

M control

Answer 36

3rd checkpoint Go -> chromosomes attached and aligned correctly no go -> not all attached/aligned

Question 37

Cell cycle depends on

Answer 37

cell type

Question 38

Cyclins

Answer 38

Proteins that regulate cell cycle by binding to CDKs (Cyclin dependent kinases) different cyclins regulate checkpoints

Question 39

Cyclin dependent kinases

Answer 39

CDK's activate with cyclins phosphorylation, activate proteins, stimulate cells into mitosis; used to fragment nuclear envelope; deactivates during anaphase cyclin breaks down -> only CDK

Question 40

Growth factors

Answer 40

affected by powerful signaling, stimulates growth

Question 41

Density dependent inhibition

Answer 41

overcrowding stops division; cell surface proteins interact

Question 42

Anchorage dependence

Answer 42

cell division requires attachment

Question 43

Programmed cell death process

Answer 43

1. Caspases (enzyme sends signal) 2. cell rounding 3. nucellus fragments 4. PM blisters (blebs) 5. Cell fragments 6. engulfed by microphages.

Question 44

Proto-oncogenes

Answer 44

"gas pedal" stimulatory (prevents apoptosis and promotes cell cycle) growth factors

Question 45

Tumor suppressor genes

Answer 45

Inhibitory (slow/inhibit cell cycle) the "breaks"

Question 46

Cancer

Answer 46

uncontrolled cell division

Question 47

Tumors

Answer 47

swelling in body caused by abnormal cell growth benign vs. malignant

Question 48

Characteristics of cancer cells

Answer 48

Lack differentiation, abnormal nuclei, do not undergo apoptosis, form tumors, and undergo metastasis (spread cancerous cells) and angiogenesis (new arteries and blood bring nutrients)