Brainscape's Knowledge GenomeTM

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


See full index

Anatomy > Cell stuff > Flashcards

Cell stuff Flashcards

1
Q

Cell

A

the basic structural and functional unit of the body

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

smooth endoplasmic reticulum

A

functions in many metabolic processes
synthesizes lipids, phospholipids, and steroids

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

rough endoplasmic reticulum

A

has ribosomes which make proteins
involved in production, folding, quality control, and dispatch of some proteins

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

lysosome

A

gets rid of waste products
scavenges metabolic building blocks that sustain essential biosynthetic reactions during starvation

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

golgi apparatus

A

receives proteins from the ER and processes and sorts them and sends them to various places in the cell

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

mitochondria

A

generates ATP through oxidative phosphorylation

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

nucleus

A

houses DNA
control center of the cell

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

how many cells are in the body

A

30-40 trillion

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

squamos cells

A

thin, flat cells with a buldge where the nucleus is
covers skin for protection, for gas diffusion (breathing/O2 exchange)

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

cuboidal cells

A

square cells, about as tall as they are wide
found in kidney -> moves ions/secretes and absorbs nutrients from blood
move cilia, operate transport proteins, etc.

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

columnar cells

A

cells that are taller than wide
found in small intestine -> absorbing and reabsorbing nutrients from food
found in respiratory tract -> moves mucus through cilia

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

polygonal cells

A

cells with irregular/angular shapes with at least 4 sides
going through a developmental process or filling space
ex. the middle layer of the epidermis

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

stellate cells

A

cells with multiple extensions
star like shape
ex. nerve cells

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

spheroid cells

A

cells that are round/ovoid
ex. adipose cells which store triglycerides for energy
ex. egg cells

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

discoid cells

A

disc shaped cells that are allowed to bend and squeeze into tiny capillaries in a single line
ex. red blood cells

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

fusiform cells

A

cells that are thick in the middle and tapered towards the end
ex. smooth muscle cells

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

fibrous cells

A

cells with a thread like shape that can contract
ex. skeletal muscle cells

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

plasma membrane

A

membrane at the cell surface that acts as the boundary between extra- and inter- cellular fluids
controls what goes in and out

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

cilia and microvilli are…

A

modifications of the plasma membrane

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

microvilli (sing. microvillus)

A

used for absorption and secretion in plasma membrane
non motile -> no mechanism for movement
increase surface area for increased absorption

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

cilia (sing. cilium)

A

longer folds of the plasma membrane
some are nonmotile but some are motile (ex. in respiratory tract)

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

list the five functions and characteristics of the plasma membrane

A
  1. boundary between the inter and extra cellular matrix
  2. encloses and supports cell contents
  3. controls interactions with other cells (recognition and communication) ex. immune system uses markers on plasma membrane to identify incoming cells
  4. maintains membrane potential
  5. controls the passage of materials in and out of the cell
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

membrane potential

A

in neurons and muscle cells
allowed because of plasma membrane
positive charge outside of cell negative charge inside of cell

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

components of intercellular fluids

A

water, proteins, sugars, fatty acids, etc. (similar to extra)
also DNA and RNA

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

components of the extracellular fluids

A

water, proteins, sugars, fatty acids, vitamins, hormones, neurotransmitters, ions, waste, etc.

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

important components of both the extra and inter cellular fluids

A

water and solutes (includes organelles, DNA, proteins, Na, Ca, and K, etc.

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

how is the plasma membrane permeable to water

A

water moves in and out through osmosis (diffusion) through a concentration gradient

28
Q

concentration gradient

A

water moves from high to low concentration of water

29
Q

what two things control the movement of water

A
  1. diffusion (osmosis)
  2. solute concentration
30
Q

why does water follow solutes

A

water forms hydration spheres by interacting with anions and cations
then there are less freely available water molecules because they are occupied in spheres and more water will move to the area with the spheres

31
Q

why does “water follows solutes” matter

A

water constantly needs to be moving to keep us alive but there is not a mechanism to move water directly
solutes CAN be moved, however, and when the solute concentration changes, the water concentration changes.
therefore water is being moved indirectly

32
Q

what is water movement important for?

A

ex.
osmoregulation in kidneys
absorption in large and small intestines
blood pressure -> pressure that is applied to blood vessels from blood

33
Q

composition (%) of plasma membrane

A

98% lipids
2% proteins
<1% carbohydrates

all 3 are very important

34
Q

makeup of plasma membrane lipids and their function

A

75% are phospholipids that function in flexibility
amphiphilic with hydrophobic tails and hydrophilic heads

20% cholesterol that functions in structure
4 ring structure with one long branch

5% glycolipids that function in identification (ex. for identifying things coming in cell by immune cells)
sugar chains

35
Q

fluid mosaic model

A

plasma membrane is neither rigid nor static in structure, instead it is highly flexible and can change its shape and composition throughout time
ex. red blood cells can bend to get into tiny capillaries

36
Q

5 impacts of a flexible plasma membrane

A
  1. flexibility of cells
  2. endo and exocytosis
  3. slight damage can easily be repaired
  4. membranes can easily fuse with each other (ex. to form tissues with adjacent cells)
  5. molecules can be moved around the entire plasma membrane (ex. can move transport proteins around to reach solutes in a different place)
37
Q

what are the two general kinds of membrane proteins

A

transmembrane and peripheral proteins

38
Q

what are transmembrane proteins

A

proteins that span the whole way of the plasma membrane

39
Q

what are peripheral proteins

A

proteins that are located on only one side of the plasma membrane

40
Q

what are some of the many functions of membrane proteins?

A

they can act as receptors, enzymes, passageways, cell-identity markers, and cell-adhesion molecules

41
Q

receptor proteins

A

used in cellular communication
are made up of a transmembrane protein and a peripheral protein attached to it on the intracellular side.
has a receptor site on the outside in which a chemical signal (ex. neurotransmitter, hormones, etc.) can bind with specificity
most are secondary messenger systems

42
Q

what are some examples of secondary messenger systems,, whats a big one thats really important

A

cAMP system, cGMP system, phosphoinositol system, arachidonic acid system, tyrokinase system
big one is G-protein coupled receptors (GCPR) as the peripheral protein

43
Q

what is GPCR

A

G (guanosine nucleoside)-protein coupled receptors
the G protein is the peripheral protein in the secondary messenger system
the body communicates with this
60% of drugs that treat diseases work through GPCRs

44
Q

explain the cAMP messenger system

A
  1. A messenger, such as epinephrine, binds to a receptor in the plasma membrane
  2. The receptor releases a G protein (the peripheral protein attached to the receptor), which then travels freely in the cytoplasm and can go on to have other various effects on the cell
  3. The G protein binds to an enzyme called adenylate cyclase in the plasma membrane. Adenylate cyclase converts ATP to cyclic AMP (cAMP) which is the second messenger
  4. cAMP activates a cytoplasmic enzyme called a kinase (elicits a response in the cell that the 1st messenger (ex. epinephrine) wanted)
  5. Kinases add phosphate groups (Psubi) to other cytoplasmic enzymes. This activates some enzymes and deactivates others, leading to varied metabolic effects in the cell.

**cAMP can either shut down or turn on Adenylate cyclase

45
Q

adenylate cyclase

A

a transmembrane enzyme to which the G-protein binds to
once the G protein binds, it converts ATP to cAMP by cleaving two of the phosphate groups off

46
Q

what is cAMP

A

the secondary messenger that is made by adenylate cyclase once the Gprotein binds
it elicits a response in a cell that the 1st messenger wanted

47
Q

example of why the secondary messenger system is important

A

beta blockers are prescribed to slow down heart rate and lower blood pressure
they block a beta-adronergic receptor (a GPCR)
Norepinephrin raises heart rate by expressing calcium channels through GPCR.
B-blockers block the binding site for Norepinephrin so that the calcium cannot get into the cell and the heart rate lowers.

48
Q

enzymes

A

catalyze chemical reactions
can be inside or outside of cell surface
ex. adenylate cyclase
ex. epithelial cells in the small intestine absorb food and nutrients through contact digestion (in contact with the enzymes on the plasma membrane)

49
Q

how are enzymes related to covid

A

ACE2 (angiotensin converting enzyme 2) is a transmembrane protein that functions as an enzyme.
Angiotensin 2 is a hormone that raises blood pressure
ACE2 breaks down angiotensin 2 and helps lower blood pressure

ACE2 is also the receptor for SARS-CoV2 to enter into the body
ACE2 receptors are highly expressed in nasal cavity (thats why they do the nasal swab for Covid tests)

50
Q

proteins acting as passageways

A

membrane proteins form tiny passageways through the plasma membrane for things like water, ions, and solutes to move through

51
Q

what are the 4 (two main two sub of 1) types of passageway proteins

A
  1. channel proteins
    Under this category there is:
    – leak channel proteins (LCP)
    – gated channel proteins (GCP)
  2. transport proteins
52
Q

leak channel proteins

A

LCPs are always open
specific to any solute and allow for movement of water and ions
based on diffusion
ex. aquaporins are specifically for water
ex. potassium leak channels

53
Q

gated channel proteins

A

allow for movement of ions
4 types –
ligand regulated
voltage regulated
mechanically regulated
photo regulated

54
Q

explain the four types of gated channel proteins

A
  1. ligand regulated - chemical signals
    ex. a sodium needs a sodium channel to open through various solutes
  2. voltage regulated - responds to change in membrane potential
    voltage change - uses electricity to communicate
  3. mechanically regulated - physical stress
    requires some force to physically open it
  4. photo regulated - light signals
    ex. the ability to see -> sodium has to stop flowing to our rods and cones
    light closes the sodium channels
55
Q

transport proteins

A

facilitate transport (also called carriers)
physically transport ions and larger solutes (ex. glucose, AA)
two types of transport - active and passive
three types of proteins - uniports, symports, and antiports

56
Q

difference between active and passive transport

A

passive - no energy required
active - energy required, proteins used are called pumps

57
Q

explain the three types of transport proteins

A
  1. uniports - transport one solute at a time in one direction
    ex. calcium pumps in most cells (dont want crystalization of calcium to form bone in cells bc that happens pretty easily)
    uses active transport
  2. symports - transport two or more solutes in the same direction at the same time
    process is called cotransport
    ex. sodium-glucose transporter
    uses passive transport
  3. antiports - transports two or more solutes in opposite directions at the same time
    process is called countertransport
    ex. sodium potassium pump (3 Na out, 2 K in)
    uses active transport
58
Q

explain how the sodium potassium pump works
what are the functions of the pump
how is it related to the Na-glucose symport

A

the transmembrane potassium pump uses ATP to bring 2 K into the cell and 3 Na out of the cell
functions:
1. establishes an electrochemical gradient - there is more sodium outside of the cell and more potassium inside of the cell
2. maintains water balance in cell - water follows solutes
3. generates heat - maintains internal body temperature, breaks down ATP to form heat
4. secondary active transport
- there is a high concentration of Na outside of the cell.
- Na-glucose move inside through the passive symport (the cells want glucose constantly bc it can store it for later, and it doesnt want the flow of glucose into the cell to stop. so they attach the glucose to Na, which is in high concentration outside of the cell, so that glucose can keep going in)

59
Q

attachment proteins

A

cell adhesion molecules (CAMs)
can be cells to other cells (desmosomes and tight junctions)
can be cells to extracellular matrix

60
Q

explain CAMs that adhere cells to other cells

A
  1. tight junctions
    -hold cells together tightly and closely
    -typically epithelial cells which prevent things from getting between cells
    ex. we dont want stomach acid to get through the epithelial cells, so tight junctions prevent that
  2. desmosomes
    -if you pull on cells, they will not tear apart.
    -hold cells tightly together
    ex. cardiac muscle -> cardiocytes contract but they are connected and do not pull apart from each other in the process because of desmosomes.
61
Q

explain CAMs that adhere cells to the extracellular material

A

required for most cells (exception: red blood cells and white blood cells can move freely and dont need CAMs)
cells need to be physically bound
ex. collagin fibers in dermis give skin flexibility but the cells in the skin are physically attached through PM proteins

62
Q

vesicular transport

A

the movement of large particles or numerous molecules through the plasma membrane
includes endocytosis, exocytosis, and transcytosis
involves vesicles (bubble like structure that is similar to the plasma membrane (bc it is the plasma membrane)

63
Q

endocytosis

A

enables cells to uptake specific molecules, receptor mediated
involves transmembrane and peripheral proteins
vesicles formed from the plasma membrane
steps:
1. extracellular molecules bind to receptors on the plasma membrane, the receptors cluster together
2. the plasma membrane sinks inward (invaginates) and forms a clathrin coated pit.
3. the pit separates from the plasma membrane, forms clathrin-coated vesicle containing concentrated molecules from the extracellular fluid

(clathrin directs the vesicle to where it goes in the cell)

64
Q

exocytosis

A

enables cells to release specific molecules
vesicles migrate to the plasma membrane
attach to peripheral proteins called linking proteins
steps:
1. a secretory vesicle approaches the plasma membrane and docks on it by means of linking proteins. The PM caves in at that point to meet the vesicle
2. The PM and the vesicle unite to form a fusion pore (basically a hole in the PM) through which the vesicle contents are released.

65
Q

transcytosis

A

transport of materials across a cell (endocytosis on one side, transport of vesicle across the cell, and exocytosis on the other side).
ex. insulin in blood stream needs to cross over the walls of the blood vessel to reach a single layer of cells right on the outside of it. so it uses transcytosis to get across the walls of the blood vessel and enters (say, a muscle cell) by binding to protein channels (insulin receptors)

66
Q

membrane proteins make up ____% of the PM weight

A

<50%

Anatomy (11 decks)

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