chp 2

Question 1

what do we mean by proteostasis ?

Answer 1

when cells need to make sure that the proteins are the right shape and working properly

Question 2

wdwm by signal transduction ?

Answer 2

the process by which cells receive , interpret and respond to signals

Question 3

what are the four phases of signal transduction ?

Answer 3

reception , transduction , response and termination

Question 4

what happens in the reception ?

Answer 4

a signal molecule (ligand ) binds to a receptor on the cells surface or inside the cell

Question 5

wt happens in transduction ?

Answer 5

when the ligand binds to the receptor , it changed the shape of the receptor this change starts an initial

Question 6

wt happens in the response ?

Answer 6

the signal inside the cell leads to a chain of reactions , they cause chemical changes to proteins

Question 7

in the response phase chemical changes to proteins (like adding or removing phosphate can lead to what ?

Answer 7

changes in activity of enzymes
changes in gene expression
changes in cell movement , shape or growth

Question 8

wt happens in the termination ?

Answer 8

once the signal has done its job it needs to stop

Question 9

neurotransmitters , hormones and cytokines are all considered wt ?

Answer 9

signals

Question 10

wt are neurotransmitters ?

Answer 10

chemicals released by nerve cells to send signals to other cells

Question 11

dopaminne and serotonin are example of wt signal

?

Answer 11

neurotransmitter

Question 12

wt are hormones

Answer 12

chemicals produced by GLANDS that travel through Blood stream to target cells

Question 13

who produces insulin and adrenaline ?

Answer 13

hormones

Question 14

wt are cytokines ?

Answer 14

these are signaling molecules produced by white blood cells that help control the immune response

Question 15

most of the prokaryotes move using ?

Answer 15

flagella

Question 16

wt is the polymer in the cell wall for the prokar ?

Answer 16

peptidoglycan it gives the cell wall strength

Question 17

wt do they do biofilms ?

Answer 17

they can cause infections like in tooth decay or cystic fibrosis

Question 18

is the outermembrane of prokaryotic cells rigid and is it permeable ?

Answer 18

it is not rigid and is permeable meaning small moecules can pass through it

Question 19

how do the small molecules pass through the prokaryotic cell wall ?

Answer 19

through the porins , they are protein coomplexes that form channels in the outer membrane

Question 20

wdym by biofilms ?

Answer 20

when bacteria group together they form a slimey layer on the surfaces

Question 21

where can we find biofilms ?

Answer 21

teeth leading to tooth decay or inside the lungs with cystic fibrosis

Question 22

wt do we have inside the bacterial cytoplasm ?

Answer 22

ribosomes , nucleoid , inclusion bodies and plasmids

Question 23

where can we find pili ?

Answer 23

on the surface of the bacteria

Question 24

wt do the pili do ?

Answer 24

they help the bacteria stick to surfaces or host tissues and we have sex pili that allow bacteria to exchange genetic materialwith other bacteria in a process called conjugation

Question 25

wdym by conjugation ?

Answer 25

how some bacteria can share antibiotic resistance genes

Question 26

wt is the structure of flagella ?

Answer 26

long , flexible , corkscrew-shaped

Question 27

flagella are made from wt ?

Answer 27

protein

Question 28

flagella are used for what ?

Answer 28

locomotion ( movement )

Question 29

wt is the function of plasma membrane in eu cells ?

Answer 29

isolates the cell from its external enviroment

Question 30

wt is the structure of plasma mambrane in eu cells ?

Answer 30

made from lipid bilayer

Question 31

wt plays an important role in cell -cell recognition and adhesion , receptor specificity and self identity ?

Answer 31

carbohydrates

Question 32

who makes and secretes the component of ecm like collagen and elastin ?

Answer 32

fibroblast

Question 33

wt are the functions of ecm ?

Answer 33

supports and protects the cell , regulates cell behavior

Question 34

wt is a membrane skeleton ?

Answer 34

network of proteins located inside the plasma membrane helping the cell keep its shape

Question 35

how does the mebrane skeleton work ?

Answer 35

is it made from actin filaments and other proteins such as spectrin and actin binding proteins these proteins connect to the plasma membrane and help stabilize it they are connected by non covalent bond

Question 36

wt helps the cell keep its shape and resist physical stress

Answer 36

membrane skeleton

Question 37

wt do we call the internal space in ER ?

Answer 37

ER lumen