Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

BIO 204 > Chapter 3: Cells: The Living Units (pgs. 54-76) > Flashcards

Chapter 3: Cells: The Living Units (pgs. 54-76) Flashcards

You may prefer our related Brainscape-certified flashcards:
Biology 101 flashcards
1
Q

cell theory

A

cell is basic structural and functional unit of living organisms
activity of organism spends on individual and combined activities of cells
principle of complementary structure and function (biochemical activities of cells are dictated by shapes or forms)
cells arise form other cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

generalized or composite cell

A

contains three main parts

  • plasma membrane: outer boundary of the cell that acts as a selectively permeable barrier
  • cytoplasm: intracellular fluid containing organelles
  • nucleus: organelle that controls cellular activities
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

extracellular materials

A

substances contributing to body mass found outside the cell

ex: body/extracellular fluids, cellular secretions, extracellular matrix

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

body/extracellular fluids

A

important transport and dissolving media
ex: interstitial fluid, blood plasma, cerebrospinal fluid
interstitial fluid baths organs in amino acids, sugars, fatty acids, regulatory substances and wastes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

cellular secretions

A

substances that aid in digestion and acts as a lubricant

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

extracellular matrix

A

most abundant extracellular material

molecules secreted by the cell self assemble into an organized mesh where they help hold cells together

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

plasma membrane

A

separates the intracellular fluid from the extracellular fluid
made up of phospholipids, glycolipids and cholesterol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

glycolipids

A

lipids with attached sugar groups
found on outer plasma membrane surface
~5% of membrane lipids
sugar groups make it polar on the outside

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

cholesterol

A

~20% of membrane lipid
wedges platelike hydrocarbon rings between phospholipid tails which stabilize the membrane and decrease mobility and fluidity of membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

integral proteins

A

firmly inserted into the lipid bilayer
most are transmembrane proteins that span the entire membrane and protrude on both sides
have hydrophobic and hydrophilic regions
involved in transport

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

channel proteins

A

transmembrane proteins involved in transport

cluster together to form pores that small, water-soluble molecules or ions can pass through

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

carrier proteins

A

bind to a substance and move it across the membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

peripheral proteins

A

not embedded in lipid bilayer, attached loosely to integral proteins and can be easily removed without disrupting the membrane
include a network of filaments that help support the membrane from the cytoplasmic side
some are enzymes, motor proteins or link cells together

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

glycocalyx

A

glycoproteins and glycolipids that form a sticky carbohydrate rich area on the cell surface
provides highly specific biological markers on different cell types that approaching cells can recognize it by

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

tight junctions

A

series of integral proteins of adjacent cells fuse together to form an impermeable junction that encircles the cell
prevent molecules from passing through extracellular space between cells (ex: stomach lining keeps acid inside)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

desmosomes

A

anchoring junctions
mechanical couplings on the sides of adjacent cells that prevent separation
abundant in tissues subjected to mechanical stress (skin or heart muscle)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

gap junction

A

communication junction between adjacent cells
hollow cylinders call connexons composed of transmembrane proteins connect cell membranes
allow ions, simple sugars and small molecules to pass through water filled channels from one cell to the next
present in electrically excitable tissues (heart and smooth muscle) where ion passage from cell to cell to help synchronize electrical activity and contraction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

connexons

A

transmembrane proteins that make up gap junctions that form hollow cylinders
different kinds vary selectivity for gap junction channel
allow ions, simple sugars and small molecules to pass through the water filled channels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

diffusion

A

tendency of molecules or ions to move from an area where they are in high concentration to an area where they are in low concentration (along concentration gradient)
speed of diffusion is related to molecular size and temperature

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

selectively permeable barrier

A

allow some substances to pass through while excluding others
plasma membrane is a barrier to free diffusion because of its hydrophobic core
allows lipids, small molecules and molecules assisted by carrier proteins through

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

simple diffusion

A

non polar and lipid-soluble substances diffuse directly through the lipid bilayer
es: O2, CO2, fat soluble vitamins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

facilitated diffusion

A

passive transport process where substances that can’t diffuse through the lipid bilayer
substances could either bind to protein carriers in the membrane and be ferried across or move through water-filled protein channels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

carrier-mediated facilitated diffusion

A

transmembrane integral proteins specific for transporting certain polar molecules or classes of molecules (sugars and amino acids) that are too large to pass through membrane channels
alterations in shape of carrier allow it to envelope and release substance so it can pass through the non polar inside of the membrane
moves down its concentration gradient

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

channel-mediated facilitated diffusion

A

transmembrane proteins that transport substances like ions or water through aqueous channels across the membrane
ex: leakage channels, gated channels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

leakage channels

A

channel-mediated facilitated diffusion
always open
allow water or ions to move across concentration gradient

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

grated channels

A

channel-mediated facilitated diffusion
controlled (opened or closed) by chemical or electrical signals
can be inhibited by certain molecules, show saturation and are specific
substances move across their concentration gradient

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

osmosis

A

diffusion of water through plasma membrane
water is highly polar, must pass through transmembrane proteins called aquaporins
occurs when water concentrations differ across a membrane

28
Q

aquaporins

A

allow single-file diffusion of water across the plasma membrane
abundant in red blood cells and kidney tubule cells

29
Q

osmolarity

A

total concentration of all solute particles in a solution

based solely on total solute concentration

30
Q

hydrostatic pressure

A

back pressure exerted by water against the membrane

31
Q

osmotic pressure

A

tendency of water to move into the cell by osmosis

32
Q

tonicity

A

ability of a solution to change the shape or tone of cells by altering the cells’ internal water volume
based on how the solution effects the cell volume which depends on solute concentration and solute permeability

33
Q

isotonic solution

A

have the same concentration of non penetrating solutes inside and outside of the cell
retain normal shape
no net loss or gain of water

34
Q

hypertonic solution

A

have a higher concentration of non penetrating solutes than the inside of the cell
cells lose water and shrink

35
Q

hypotonic solution

A

more dilute than the cells

cells gain water rapidly and will lyse

36
Q

active transport

A

requires carrier proteins that combine specifically and reversibly with the transported substances
move solutes against a concentration gradient using energy

37
Q

primary active transport

A

energy comes directly from hydrolysis of ATP

ex: calcium and hydrogen pumps, sodium-potassium pump

38
Q

secondary active transport

A

energy is tired in concentration gradients of ions created by primary active transport pumps
coupled systems that move more than one substance at a time
ex: in Na+-K+ pump a Na+-glucose symport transporter loads glucose from outside the cell and transports both inside the cell

39
Q

symport

A

two transported substances move in the same direction

40
Q

antiport

A

substances are transported across the membrane in opposite directions

41
Q

Na+-K+ ATPase

A

enzyme that functions in the sodium-potassium pump

42
Q

vesicular transport

A

fluids containing large particles and macromolecules are transported across the membrane inside membranous sacs called vesicles

43
Q

endocytosis

A

vesicular transport moves substances into cell

44
Q

exocytosis

A

vesicular transport moves substances out of the cell
typically stimulated by a cell-surface signal like binding of a hormone or change in membrane voltage
ex: hormone secretion, neurotransmitter release, mucus secretion and waste secretion

45
Q

transcytosis

A

combination processes that move substances into, across, and then out of the cell

46
Q

vesicular trafficking

A

moving substances from one area (membranous organelle) in the cell to another

47
Q

coated pit

A

vesicles have a coating found on their face

acts to select the cargo in the vesicle and deforming the membrane to produce the vesicle

48
Q

lysosome

A

specialized cell structure containing digestive enzymes where ingested substances is degraded or released

49
Q

phagocytosis

A

type of endocytosis
cell engulfs relatively large or solid material (ex: clump of bacteria, cell debris etc.)
particles bind to receptors on the cells surface and cytoplasmic extensions called pseudopods form and flow around the particle to form a phagosome

50
Q

amoeboid motion

A

how phagocytes move

cytoplasm flows into temporary extensions

51
Q

pinocytosis

A

“cell drinking” or fluid-phase endocytosis
infolding plasma membrane surrounds a small volume of extracellular fluid containing dissolved molecules and enters the cell and fuses with an endosome
routine activity of most cells
how cells absorb nutrients
membranes are recycled back to the plasma membrane by exocytosis

52
Q

receptor-mediated endocytosis

A

specific endocytosis and transcytosis
cells can take in materials from outside the cell that are in small concentrations
receptor and molecule are internalized in a clathrin-coated pit
ex: enzymes, insulin, low density lipoproteins and iron

53
Q

v-SNAREs

A

v = vesicle
transmembrane protein on a vesicle that recognizes certain plasma membrane proteins and bind with them to fuse the vesicle and membrane

54
Q

t-SNAREs

A

t = target

plasma membrane protein that v-SNAREs bind to to fuse vesicle with membrane

55
Q

membrane potential

A

voltage across a membrane

56
Q

voltage

A

electrical potential energy resulting from the separation of oppositely charge particles

57
Q

resting membrane potential

A

-50 to -100 mV for an average cell depending on type
cells are polarized because the inside of the cell is negative compared to the outside
voltage exists only at the membrane

58
Q

maintaining resting potential

A

K+ diffuses out of the cell through K+ leakage channels and negatively charged proteins are too large to follow and the membrane interior becomes negative
K+ will be attracted back into the cell by the - charge
at -90 mV K+ concentration gradient is balanced by the electrical gradient

59
Q

cell adhesion molecules (CAMs)

A

play a key role in embryonic development, wound repair and immunity
sticky glycoproteins that act to
- anchor cells to the extracellular space and each other
- haul migrating cells past one another
- SOS signals to recruit white blood cells to an infected or injured area
- mechanical sensors to respond to changes in local tension or fluid movement at cell surface by stimulating synthesis or degradation of tight junctions
-transmitters of intracellular signals that direct cell migration, proliferation, and specialization

60
Q

membrane receptors

A

integral proteins and glycoproteins that serve as binding sites

61
Q

contact signaling

A

cells come together and touch
how cells recognize one another
important for normal development and immunity

62
Q

ligands

A

chemicals that bind specifically to plasma membrane receptors
ex: most neurotransmitters, hormones and paracrines

63
Q

G protein-linked receptors

A

exert effect indirectly through a G protein which generate one or more intracellular chemical signals that connect plasma membrane events to internal metabolic machinery of the cell

64
Q

G protein

A

regulatory molecule that acts as a middleman or relay to activate or inactivate a membrane-bound enzyme or ion channel

65
Q

second messengers

A

intracellular chemical signals that connect the plasma membrane to cell machinery
ex: cyclic AMP, ionic calcium

66
Q

cyclic AMP

A

typically activate protein kinase enzymes that transfer Pi from ATP to other proteins, activating a series of enzymes that bring about the desired cellular activity

67
Q

protein kinase enzymes

A

transfer Pi from ATP to other proteins, activating a series of enzymes that bring about the desired cellular activity

BIO 204 (5 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions