Cell membranes

Question 1

what penetrates the hydrophobic core of the lipid bilayer and the hydrophobic regions of an integral protein consist of one or more stretches of non polar amino acids

Answer 1

integeral proteins

Question 2

these are not embedded in the lipid bilayer at all, they are appendages loosely bound to the surfaece of the membrane

Answer 2

peripheral proteins

Question 3

what is it called when membrane proteins of adjacent cells hook toghether in various junctions, such as gap junctions or tight junctions

Answer 3

intracellular joining

Question 4

whats function is by having a hydrophobic channel that certain molecules or atomic ions use as a tunnel through the membrane

Answer 4

channel proteins

Question 5

the passage of water molecules through the membrane in certain cells is generally facilitated by channel proteins known as ______

Answer 5

aquaporins

Question 6

the diffusion oa a substance across a biological membrane is called ______ _______ because the cell does not have to expend energy to make it happen

Answer 6

passive transport

Question 7

is a cell with out a wall is immersed in an environment that is _____ to the cell and there will be no net movement of water across the plasma membrane

Answer 7

isotonic

Question 8

if a solution is _______ to the cell the solution has more solutes than the cell and the cell will lose water to its environment and shrivel and die

Answer 8

hypertonic

Question 9

is a solution is ___ to the cell the solution has a lower solute concentration than the cell so therefor water will enter the cell and cause it to swell and potentially burst. lysis

Answer 9

hypotonic

Question 10

what is the name given to the control of water balance

Answer 10

osmoregulation

Question 11

another group of channes are called _____ channels and many of these function as gated channels, a stimulus causes them to open or close

Answer 11

ion

Question 12

____ ____ is when the cell must expend energy because the molecule is being pumped across the membrane down against the concentration gradient.

Answer 12

active transport

Question 13

____ ____ is the charge difference between a cells cytoplasm and the extracellular fluid, due to the differential distribution of ions.

Answer 13

membrane potential

Question 14

a transport protein that generates voltage across a membrane is called a _____ _____

Answer 14

electrogenic pump

Question 15

a single ATP powered pump that transports a specific solute can directly drive the active transport of several other solutes in a mechanism called ______

Answer 15

co-transport

Question 16

_______ is when the cell secreted macromolecules by the fusion of vesicles with the plasma membrane

Answer 16

exocytosis

Question 17

in _____ the cell takes in macromolecules and particular matter by forming new vesicles from the plasma membrane

Answer 17

endocytosis

Question 18

a ____ is the general term for any specific molecule that binds specifically to a receptor site of another molecule

Answer 18

lingand

Question 19

what is the function of the cell membrane

Answer 19

seperates the cell from the outside environment and controls what enters and leaves the cell.

Question 20

what causes the cell membrane to be partially permeable

Answer 20

the phospholipid bilayer and its components

Question 21

what do proteins and fats do in the cell membrane

Answer 21

allow receptors to bind and provide structural integrity

Question 22

what is the function of the cytoplasm

Answer 22

holds everything inside the cell and outside the nucleus. maunly mase up of fluids. keeps everything in the cell in place.

Question 23

what is the function of the nucleus

Answer 23

controlls everything that happens in the cell
regulates DNA and RNA actions
it is a membrane bound organelle that protects the DNA

Question 24

what is the function of the nuclear envelope that surrounds the nucleus

Answer 24

protects the nucleus. there are ribosomes present to help with protein synthesis.
the envelope has nuclear pores that help to control what can enter or leave the nucleus.
it is made with a double layer of lipids which make it semi-permeable

Question 25

what is the fucntion of the nucleolus

Answer 25

this is where ribosomal RNA is made

Question 26

what is the fucntion of the rough endoplasmic recticulum

Answer 26

contains ribosomes and helps with protein synthesis. processes and folds proteins

Question 27

what is the function of the smooth endoplasmic recticulum

Answer 27

synthesis and processing of lipids, prominent in drug metabolism . more tubular than RER

Question 28

what is the fucntion of lysozomes

Answer 28

its a vesicle containing digestive enzymes ot breakdown worn out cells or foreign objects. it is a membrane bound organelle

Question 29

what is the fucntion of the mitochondria

Answer 29

membrane bound organelle used for aerobic respiration. involves in the synthesis of ATP. contains DNA, and the folding of the internal membrane increases the surface area for respiration to occur

Question 30

what is the fucntion of the golgi apparatus

Answer 30

sorts and processes molecules that need to be transported out of the cell and around the body It can change a protein . addition of other molecules to change the shape and the function. Processes proteins, cleavage of peptides to produce activated proteins Sorting and isolation of proteins.

Question 31

what is the structure of the nucleus entail

Answer 31

. Nucleolus. Chromatins, nuclear envelope. Nuclear lamina (part of the nuclear envelope), nucleoplasm, Nucleoplasm is the amorphous fluid (no distinct shape). Contains components such as proteins, rna ribonucleoproteins and small molecules. Plus fibrous chromatin (50% protein and 50% dna) which occupies about 80-90% of the nuclear volume.

Question 32

what is the overall function of the SER and the RER

Answer 32

detoxification of drugs translocation of proteins glycosylation of proteins- adding sugars to other molecules and proteins assembly of lipid bi-layers

Question 33

what is cellular digestion?

Answer 33

lysosomes fuse with the food vacuole, polymers are digested into monomers. this is passed to the cytosol to become the nutrients of the cell.