unit 4 ap bio

Question 1

signal transduction pathway

Answer 1

Convert signals on a cell’s surface into cellular responses

Question 2

local regulators

Answer 2

messenger molecules that travel short distances

Question 3

horomones

Answer 3

chemicals that plants and animals use in long distance signaling

Question 4

3 processes that cells who receive signals go through

Answer 4

1) reception
2) transduction
3) response

Question 5

reception

Answer 5

A cell detects a signaling molecule from the outside of the cell

Question 6

transduction

Answer 6

signal sensed by the receptor protein is transmitted to the inside of the cell

Question 7

response

Answer 7

A response is a change in cellular behavior due to the signal

Question 8

ligand

Answer 8

signal molecule

Question 9

G protein-coupled receptor

Answer 9

plasma membrane receptor that works with help of G protein

Question 10

G protein

Answer 10

acts as on/off switch, if GDP is bound to G protein then G protein is inactive

Question 11

receptor tyrosine kinase

Answer 11

membrane receptors that attach phosphates to tyrosines, trigger multiple signal transduction pathways at once

Question 12

ligand gated ion channel

Answer 12

receptor acts as a gate when the receptor changes shape
when signal molecule binds as a ligand to receptor, gate allows specific ions (Na+, Ca2+) through a channel in the receptor

Question 13

protein kinase

Answer 13

transfer phosphates from ATP to protein in a process called phosphorylation

Question 14

protein phosphates

Answer 14

remove phosphates from proteins in a process called dephosphorylation

Question 15

second messengers

Answer 15

small, nonprotein, water soluble molecules or ions that spread throughout a cell by diffusion

Question 16

cyclic AMP or cAMP

Answer 16

most widely used second messenger, activates protein kinase A

Question 17

adenylyl cyclase

Answer 17

enzyme in plasma membrane, converts ATP to cAMP in response to extracellular signal

Question 18

phases of the cell cycle

Answer 18

G1 or G0, S, G2, M

Question 19

what is the purpose of cell cycle

Answer 19

development from fertilized egg
growth
repair
produce two identical daughter cells

Question 20

how does cell cycle contribute to growth and repair

Answer 20

the cycle allows for our body to repair damaged cells and produce new stronger ones so we can stay healthy

Question 21

difference between chromatid and chromatin

Answer 21

Chromatin is the DNA and proteins that make up a chromosome.
Chromatids are identical pieces of DNA held together by a centromere

Question 22

difference between mitosis and cytokinesis in plant and animal cells

Answer 22

mitosis in animals- mitotic spindle is formed w the help of two centrioles
mitosis in plants- mitotic spindle is formed without any help
plant cytokinesis- cytoplasmic division starts at center and moves towards cell wall
animal cytokinesis- cytoplasmic division starts at edges of cell at plasma membrane and moves towards center

Question 23

somatic cell

Answer 23

nonreproductive cell, two sets of chromosomes

Question 24

gametes

Answer 24

reproductive cells; sperm and egg, half as many chromosomes as somatic

Question 25

centromere

Answer 25

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

Question 26

what does meiosis yield

Answer 26

nonidentical daughter cells that have only one set of chromosomes, half as many parent cell

Question 27

centrosome

Answer 27

where the assembly of spindle microtubules begin, “microtubule organizing center”

Question 28

mitotic spindle

Answer 28

apparatus of microtubules that control chromosome movement during mitosis

Question 29

compare mitosis and meiosis

Answer 29

mitosis is division of nucleus and meisosis produces gametes (sex cells)

Question 30

paracrine signaling

Answer 30

allows cells to communicate with each other by releasing signaling molecules that bind to and activate surrounding cells

Question 31

scafolding protein

Answer 31

large relay proteins to which other relay proteins are attached
can increase signal transduction efficiency by grouping together different proteins involved in same pathway

Question 32

apoptosis

Answer 32

programmed or controlled cell suicide
chopped and packed into vesicles that are digested by scavenger cells
prevents enzymes from leaking out of dying cell and damaging neighbor cells

Question 33

phosphorylation cascade

Answer 33

sequence of signaling pathway events where one enzyme phosphorylates another , causing a chain reaction leading to the phosphorylation of thousands of proteins

Question 34

what triggers apoptosis

Answer 34

extracellular death signaling ligand
DNA damage in nucleus
protein misfolding in endoplasmic reticulum