Cellular Biology

Question 1

Facilitated Diffusion

Answer 1

the net movement of dissolved particles down their concentration gradient through special channels - does not require energy

Question 2

Active Transport

Answer 2

the net movement of dissolved particles against their concentration gradients with the help of transport proteins - requires energy

Question 3

Symporter

Answer 3

moves two or more ions or molecules in the same direction

Question 4

Antiporter

Answer 4

exchange one or more ions for another ion or molecule

Question 5

Pumps

Answer 5

energy-dependent carriers (require ATP)

Question 6

Endocytosis

Answer 6

a process in which the cell membrane invaginates

Question 7

Pinocytosis

Answer 7

the ingestion of fluids or small particles

Question 8

Phagocytosis

Answer 8

the engulfing of large particles

Question 9

Exocytosis

Answer 9

a vesicle within the cell fuses with the cell membrane & releases a large volume of contents to the outside

Question 10

brownian movement

Answer 10

kinetic energy spreads small suspended particles throughout the cytoplasm of the cell

Question 11

cytosis or streaming

Answer 11

the circular motion of cytoplasm around the cell transports

Question 12

endoplasmic reticulum

Answer 12

the ER forms a network of channels throughout the cytoplasm & provides a direct continuous passage from the plasma membrane to the nuclear membrane

Question 13

diffusion

Answer 13

sufficient means of transport for food & oxygen from the environment to the cells

Question 14

circulatory system

Answer 14

includes vessels to transport fluid & a pump to drive the circulation

Question 15

Cell Division

Answer 15

the process by which a cell doubles its organelles & cytoplasm, replicates its DNA & then divides in two

Question 16

Interphase (mitosis)

Answer 16

a period of growth & chromosome replication

a cell spends 90% of its life time in interphase

Question 17

G1 phase

Answer 17

the phase that initiates interphase
the active growth phase & can vary in length
the cell increases in size & synthesizes proteins
the length of the G1 phase determines the length of the entire cycle

Question 18

S phase

Answer 18

the period of DNA synthesis

Question 19

G2 phase

Answer 19

the cell prepares to divide

it grows & synthesizes proteins

Question 20

M phase

Answer 20

the last phase of the cell cycle
this is where mitosis or meiosis occurs
results in 2 or 4 non-identical daughter cells

Question 21

Mitosis

Answer 21

the division & distribution of the cell’s DNA to its two daughter cells such that each cell receives a complete copy of its original genome
takes place in somatic cells

Question 22

Prophase (mitosis)

Answer 22

the chromosomes condense & the centriole pairs separate & move toward the opposite poles of the cell

Question 23

Metaphase (mitosis)

Answer 23

the centriole pairs are now at opposite poles of the cell
the fibers of the spindle apparatus attach to each chromatid & its corresponding kinetochere (protein location)
the spindle fibers align the chromosomes @ the center of the cell, forming the metaphase plate

Question 24

Anaphase (mitosis)

Answer 24

the centrioles split so that each chromatid has its own distinct centrome, allowing sister chromatids to separate
The sister chromatids are pulled toward the opposite poles of the cell by the shortening spindle fibers

Question 25

Cytokinesis (mitosis)

Answer 25

division into two daughter cells each with a complete nucleus & its own set of organelles

Question 26

Meiosis

Answer 26

similar to mitosis, but produces haploid cells (halving the # of chromosomes) involves two divisions of primary sex cells resulting in four haploid cells called gametes

Question 27

Interphase (meiosis)

Answer 27

the parent cell's chromosomes are replicated, resulting in the 2N number of sister chromatid

Question 28

Prophase I (meiosis)

Answer 28

chromatin condenses into chromosomes, spindle forms, & the nucleoli & nuclear membrane disappears

Question 29

synapsis

Answer 29

homologous chromosomes come together & intertwince

Question 30

tetrad

Answer 30

2 sister chromatids - contain 4 chromatids

Question 31

crossing over

Answer 31

when chromosomes exchange equivalent pieces of DNA (cannot occur with sister chromatids)

Question 32

chiasmata

Answer 32

the points of contact between homologous chromosomes where crossing over can occur

Question 33

Metaphase I (meiosis)

Answer 33

homologous pairs align at the equatorial plane & each pair attaches to a separate spindle fiber at the kinetochere

Question 34

Anaphase I (meiosis)

Answer 34

the homologous pairs separate & are pulled to opposite poles of the cell (disjunction) mother chromatid forms a daughter chromatid

Question 35

nondisjunction

Answer 35

occurs when cells do no separate appropriately during meiosis, results in the daughter cells having an incorrect # of chromosomes

Question 36

Telophase I (meiosis)

Answer 36

a nuclear membrane forms around each new nucleus

Question 37

second meiotic division

Answer 37

chromosomes align at the equator, separate & move to opposite poles & are surrounded by a re-formed nuclear membrane