Unit 4

Question 1

What is direct communication?

Answer 1

Communication through cell junction

Question 2

Animals use _____ for direct communication?

Answer 2

Gap junctions

Question 3

Plants use _____ for direct communication?

Answer 3

Plasmodesmata

Question 4

What is local regulation?

Answer 4

Cell releasing chemical message to travel through extracellular fluid

Question 5

What is paracrine signaling?

Answer 5

Secretory cells release regulators through exocytosis to adjacent cells

Question 6

What is synaptic signaling?

Answer 6

Neurons in animal nervous systems secrete neurotransmitters that diffuse across synaptic cleft

Question 7

What is long distance signaling?

Answer 7

Communication using hormones to reach target cells

Question 8

Plants use their _____ to do long distance signaling?

Answer 8

Xylem

Question 9

Animals use their _____ to do long distance signaling?

Answer 9

Endocrine system, which sends hormones into circulatory system

Question 10

What are three stages of cell to cell messaging?

Answer 10

Reception, transduction, and response

Question 11

What happens in reception?

Answer 11

Ligand binds to receptor

Question 12

What happens in transduction?

Answer 12

Signal is converted

Question 13

What happens in response?

Answer 13

Cell process is altered

Question 14

What do plasma membrane receptors bind to?

Answer 14

Large, polar molecules

Question 15

Where are intercellular receptors found?

Answer 15

Cytoplasm or nucleus

Question 16

What does the signal transduction pathway do?

Answer 16

Regulates protein activity

Question 17

What does kinase do?

Answer 17

Phosphorylates by relaying signal inside cell

Question 18

What does phosphatase do?

Answer 18

Dephosphorylates by shutting off pathways

Question 19

What are second messengers?

Answer 19

Small molecules that help relay messages and amplify response (ex: cAMP)

Question 20

Functions of the signal transduction pathway in cells?

Answer 20

Can affect gene expression, cell function, and phenotypes

Question 21

Where is the ligand gated ion channel located?

Answer 21

Plasma membrane

Question 22

What is a stimulus?

Answer 22

Variable that causes a response

Question 23

What is an effector?

Answer 23

Muscle or gland that responds to stimulus

Question 24

What does negative feedback do?

Answer 24

Reduces stimulus effect

Question 25

What does positive feedback do?

Answer 25

Increases stimulus effect

Question 26

How are nucleosomes formed?

Answer 26

DNA wraps around histone protein

Question 27

What is chromatin?

Answer 27

Strings of nucleosomes

Question 28

What are chromosomes?

Answer 28

Condensed chromatin

Question 29

What are sister chromatids?

Answer 29

A pair of duplicated chromosomes?

Question 30

What is the connecting region of sister chromatids?

Answer 30

Centromeres

Question 31

What protein attaches the sisters to spindle fibers?

Answer 31

Kinetochores

Question 32

What is a genome?

Answer 32

All of a cell’s genetic information

Question 33

Which cell has a singular, circle DNA?

Answer 33

Prokaryotes

Question 34

Which cell has multiple, linear DNA?

Answer 34

Eukaryotes

Question 35

What are homologous chromosomes?

Answer 35

One gene from mom and the other from dad

Question 36

What are somatic cells?

Answer 36

Diploid (2n) homologous body chromosomes

Question 37

How do somatic cells divide?

Answer 37

Mitosis

Question 38

2n = 46?

Answer 38

# of human somatic cells

Question 39

What are gametes?

Answer 39

Set of haploid (n) reproductive chromosomes

Question 40

How are gametes divided?

Answer 40

Meiosis

Question 41

n = 23?

Answer 41

# of human gametes

Question 42

What are the stages of mitosis?

Answer 42

G1, S, G2, mitosis, cytokinesis

Question 43

What happens in G1?

Answer 43

Cell grows and functions normally

Question 44

What happens in S?

Answer 44

DNA replication and chromosome duplication

Question 45

What happens in G2

Answer 45

Final growth and prep for mitosis

Question 46

What are the phases of mitosis?

Answer 46

Prophase, prometaphase, metaphase, anaphase, telophase + cytokinesis

Question 47

What happens in prophase?

Answer 47

- chromatin condense - nucleoli disappears - mitotic spindle forms - centrosomes move away from eachother

Question 48

What happens in prometaphase?

Answer 48

- nuclear envelope fragments

Question 49

What happens in metaphase?

Answer 49

- centrosomes are at opposite poles - chromosomes line at metaphase plate - microtubules attach to kinetochores

Question 50

What happens in anaphase?

Answer 50

- sisters separate and move to opposite sides bc of shortened microtubules - cell elongates

Question 51

What happens in telophase?

Answer 51

- two daughter nuclei form - nucleoli reappear - chromosomes uncondense

Question 52

What happens in animal cytokinesis?

Answer 52

Cleavage furrow forms

Question 53

What happens in plant cytokinesis?

Answer 53

Golgi vesicles form a plate in middle of cell

Question 54

What happens in the G1 checkpoint?

Answer 54

Cell size, growth, and DNA damage is checked, then either sent to mitosis or G0

Question 55

What happens in the G0 checkpoint?

Answer 55

Some cells (muscle and nerve) can stay forever or be called back into cycle

Question 56

What happens in G2 checkpoint?

Answer 56

DNA replication and damage is checked for, if it stops there and can’t repair itself, apoptosis happens

Question 57

What happens in the M checkpoint?

Answer 57

Checks for microtubule attachment, if not the cycle will stop until they do

Question 58

What do cyclins and CDK do?

Answer 58

Help internally regulate events in the cell cycle