The Cell Part V

Question 1

special form of cell division

Answer 1

MEIOSIS

Question 2

sex cells divide this type

Answer 2

MEIOSIS

Question 3

chromosome number is reduced from diploid (2n) to haploid (n)

Answer 3

MEIOSIS

Question 4

occurs in developing germ cells (spermatozoa and oocytes), fertilization results in diploid zygotes

Answer 4

MEIOSIS

Question 5

doubling of DNA content in S phase

Answer 5

MEIOSIS

Question 6

Affected by 2 successive cell divisions that give rise to 4 haploid cells
- accompanied by recombination of maternal and paternal genes by crossing over and random assortment.

Answer 6

MEIOSIS

Question 7

2 STAGES OF MEIOSIS:

Answer 7

A. REDUCTIONAL DIVISION (MEIOSIS I)
B. EQUATORIAL DIVISION (MEIOSIS II)

Question 8

occurs following the interphase during which 46 chromosomes are duplicated giving the cell a 4 CDNA content (total DNA content of the cell).

Answer 8

REDUCTIONAL DIVISION (MEIOSIS I)

Question 9

5 stages of Prophase I:

Answer 9

a) LEPTOTENE
b) ZYGOTENE
c) PACHYTENE
d) DIPLOTENE
e) DIAKINESIS

Question 10

chromatin condenses into visible chromosomes

Answer 10

LEPTOTENE

Question 11

each contains 2 chromatids joined at the centromere.

Answer 11

LEPTOTENE

Question 12

homologous maternal and paternal chromosomes pair and make physical contact (synapsis) via the synaptonemal complex, forming a tetra

Answer 12

ZYGOTENE

Question 13

chiasmata are formed

Answer 13

PACHYTENE

Question 14

crossing over occurs

Answer 14

PACHYTENE

Question 15

random exchange of genes between segments of homologous chromosomes

Answer 15

PACHYTENE

Question 16

increasing genetic diversity

Answer 16

PACHYTENE

Question 17

chromosomes continue to condense

Answer 17

DIPLOTENE

Question 18

chiasmata can be observed indicating sites where crossing over has taken place

Answer 18

DIPLOTENE

Question 19

nucleolus disappear

Answer 19

DIAKINESIS

Question 20

Chromosomes are condensed maximally

Answer 20

DIAKINESIS

Question 21

nuclear envelope disappears

Answer 21

DIAKINESIS

Question 22

begins soon after completion of meiosis I, following a brief interphase without DNA replication

Answer 22

EQUATORIAL DIVISION (MEIOSIS II)

Question 23

separation of sister chromatids and distribution into 4 daughter cells (gametes) each containing the haploid number of chromosomes

Answer 23

EQUATORIAL DIVISION (MEIOSIS II)

Question 24

Structure:

Phospholipid bilayer containing cholesterol and proteins (integral and peripheral) and some carbohydrates (externally)

Answer 24

Plasma Membrane

Question 25

Structure: forms a selectively permeable boundary of the cell.

Answer 25

Plasma Membrane

Question 26

acts as a physical barrier to enclose cell contents

Answer 26

Plasma Membrane

Question 27

regulates material movement into and out of the cell

Answer 27

Plasma Membrane

Question 28

establishes and maintains an electrical charge difference across the plasma membrane

Answer 28

Plasma Membrane

Question 29

functions in cell communication

Answer 29

Plasma Membrane

Question 30

Short, numerous (many) membrane extensions supported by microtubules which occur on exposed membrane surfaces of some cells

Answer 30

Cilia

Question 31

which occur on exposed membrane surfaces of some cells

Answer 31

Cilia

Question 32

Long, singular (only one) membrane extension supported by microtubules

Answer 32

Flagellum

Question 33

present in sperm cells

Answer 33

Flagellum

Question 34

propels sperm

Answer 34

Flagellum

Question 35

Numerous thin membrane folds projecting from the free cell surface;

Answer 35

Microvilli

Question 36

supported by microfilaments

Answer 36

Microvilli

Question 37

Large structure enclosed within a double membrane;

Answer 37

Nucleus

Question 38

contains chromatin, nucleolus, and neoplasm

Answer 38

Nucleus

Question 39

houses the DNA that serves as the genetic material for directing protein synthesis.

Answer 39

Nucleus

Question 40

double membrane boundary between cytoplasm and nuclear contents

Answer 40

Nuclear Envelope

Question 41

continuous with rough endoplasmic reticulum

Answer 41

Nuclear Envelope

Question 42

separates nucleus from cytoplasm

Answer 42

Nuclear Envelope

Question 43

openings through the nuclear envelope

Answer 43

Nuclear Pores

Question 44

allow passage of materials between the cytoplasm and nucleoplasm, including ribonucleic acid (RNA), protein, ions, and small water-soluble molecules.

Answer 44

Nuclear Pores

Question 45

large, prominent structure within the nucleus

Answer 45

Nucleolus

Question 46

functions in synthesis of ribosomes

Answer 46

Nucleolus

Question 47

contents of cells between the plasma membrane and nuclear envelope

Answer 47

Cytoplasm

Question 48

responsible for many cellular processes

Answer 48

Cytoplasm

Question 49

viscous fluid medium with dissolved solutes (e.g., ions, proteins, carbohydrates, lipids)

Answer 49

Cytosol

Question 50

provides support for organelles

Answer 50

Cytosol

Question 51

serves as the viscous fluid medium through which diffusion occurs

Answer 51

Cytosol