Genbio w3 (cell cycle and mitosis)

Question 1

An integral part of the cell cycle

Answer 1

Cell division

Question 2

Key roles of cell division

Answer 2

-The ability of organisms to reproduce distinguishes living things from nonliving matter
-continuity of life is based on reproduction of cells or cell division

Question 3

In unicellular organisms, division of one cell reproduces the entire organism. Multicellular organisms depend on cell division for:

Answer 3

-development from a fertilized cell
-growth
-repair

Question 4

DNA molecules in a cell are packaged into what

Answer 4

chromosomes

Question 5

Every eukaryotic species has a certain number of chromosomes in each nucleus. Humans have how many chromosomes

Answer 5

46 (23 pairs)

Question 6

nonreproductive cells that have 2 sets of chromosomes.
i.e. body cells

Answer 6

Somatic cells

Question 7

Reproductive cells (sperm and eggs) have half as many chromosomes as somatic cells

Answer 7

Gametes

Question 8

Eukaryotic chromosomes consist of ______, a complex of DNA and protein that condenses during cell division

Answer 8

chromatin

Question 9

Half a number of chromosomes

Answer 9

Haploid

Question 10

Complete set of chromosomes

Answer 10

Diploid

Question 11

Genetic information

Answer 11

DNA (Deoxyribonucleic Acid)

Question 12

DNA + Histones (proteins)

Answer 12

chromatin

Question 13

coiled chromatin fibers

Answer 13

chromosome

Question 14

one of the duplicated chromosome

Answer 14

chromatid

Question 15

most cell division results in daughter cells with identical genetic information. DNA

(basa lang)

Answer 15

-

Question 16

-All the DNA in a cell constitutes the cell’s _______
-consist of a single DNA molecules (common in prokaryotic cells) or a number of DNA molecules (common in eukaryotic cells)
-entirety of DNA identity

Answer 16

Genome

Question 17

The narrow “waist” of the duplicated chromosome, where the two chromatids are most closely attached

Answer 17

centromere

Question 18

-The division of nucleus
-for cell regeneration, growth and development

Answer 18

Mitosis

Question 19

The division of cytoplasm

Answer 19

Cytokinesis

Question 20

Yields nonidentical daughter cells that have only one set of chromosomes, half as many as the parent cell (gametes, sperm cell and egg cell)

Answer 20

Meiosis

Question 21

About 90% of the cell cycle

Answer 21

Interphase

Question 22

Subphases of interphase

Answer 22

G1 phase (“first gap”)
S phase (synthesis)
G2 phase (second gap)

Question 23

What happens in G1 phase

Answer 23

-RNA and protein synthesis
-cell size increases for the preparation for cell division
- other terms are post-mitotic phase or pre synthetic phase
-longest phase

Question 24

What happens in S phase

Answer 24

DNA synthesis/duplication

Question 25

What happens in g2 phase

Answer 25

Duplication of organelles for the duplicated cell to function

Question 26

Cetain cells cannot reporduce like the nerve cells because they do not go through the normal interphase process (G0). What happens in gap 0 phase.

Answer 26

-also referred to as the Quiescent phase (meaning inactivity or dormancy)
-cells don’t grow or differentiate
-cell cycle arrest

cells can re-enter normal cell cycle if there’s stimulation of mitogens

Question 27

Characteristics/events in interphase

Answer 27

-Formation of centrosomes (with centriole pairs)
-nuclear envelope is still present
-chromatin (duplicated) but not yet condensed

Question 28

Characteristics/events in prophase

Answer 28

-appearance of early mitotic spindle fibers
-things start to move inside
-stretching of microtubules emerged from centrosome
-degration of nuclear envelope to give way for chromosome condensation
-condensation of chromatin into becoming a chromosome (and these duplicated chromosome appear as sister chromatids)

Question 29

Characteristics/events of prometaphase

Answer 29

-microtubules elongate
-has kinetochore and nonkinetochore microtubules
-greated condensation of chromosomes (distinct x shape of chromosomes are observed)
-fragments of nuclear envelope are still left/almost completely dissolved

Question 30

Difference of kinetochore and nonkinetochore

Answer 30

the kinetochore microtubules attach to chromosomes and move them towards poles.
nonkinetochore microtubules are responsible for elongating the cell during anaphase.

Question 31

Characteristics/events of metaphase

Answer 31

-centrosome pairs moved to opposite poles of the side
-microtubules aligned your sister chromatids in the center of the cell after the tug-of-war situation (metaphase plate)
-full blown spindle fibers

Question 32

Characteristics/events of anaphase

Answer 32

-shortest stage of mitosis
-sister chromatids separate (after separate, they are now called chromosomes)
-kinetochore microtubules pull chromosomes to the respective centrosomes
-nonkinetochore elongate the cell

Question 33

Characteristics/events of telophase and cytokinesis

Answer 33

-cytoplasm simultaneously divides (cytokinesis)
-reformation of nucleolus
-nuclear envelop reforms
-chromosome become less condensed
-microtubules depolymerize (or shrink)
-tightening in the middle (cleavage furrow)

instead of a cleavage furrow, plants have cell plate

Question 34

Do plant cells have centrosome?

Answer 34

no, they instead have spindle microtubules organizing center

*vesicles form cell plate derived from the Golgi apparatus

Question 35

What is the asexual reproduction of new organisms

Answer 35

Binary fission