A&p Ch 3: Cells: The Living Units

Front 1

Phospholipid

Back 1

Front 2

What is charged and what is not? Hydrophilic and hydrophobic

Back 2

Hydrophilic is polar and charged while hydrophobic is non-polar and not charged.

Front 3

A majority of phospholipids are unsaturated and it kinds their tails, what does this do?

Back 3

Increases the space between them and increases membrane fluidity.

Front 4

Glycolipids

Back 4

Lipids with attached sugar groups, found only on the outer plasma membrane. Sugar groups are polar, while tails remain nonpolar.

Front 5

Lipid Rafts

Back 5

Dynamic assemblies o fsaturated phopholipids associtaed with unique lipids called sphingolipids. Can include or exclude specific proteins. Used for receptor molecules or for molecules needed in cell signaling.

Front 6

Proteins make up half the plasma membrane by mass and are responsible for specialized functions. What are the two distinct populations of membrane proteins?

Back 6

Integral proteins and peripheral proteins.

Front 7

Integral proteins

Back 7

Most are transmembrane proteins that span the whole membrane. Have hydrophobic/phylic regions. Some form channels/pores through which small water soluble molecules or ions can move. others act as carriers that bind a substance and move it through the membrane. Others are recepeors for hormones or other chemical messangers. and relay messages t the cell interior (signal transduction)

Front 8

Peripheral proteins

Back 8

Not imbedded in the membrane but can be easily removed with out disrupting the membrane. Include filaments that support the membrane from the cytoplasm. Some are ezymes, others are motor proteins involved in mechanical functions such as muscle cell contractions, others link cells together, some float freely while most are tethered to the cytoskeleton.

Front 9

Glycocalyx

Back 9

Fuzzy, sticky, carbodydrate rich area at the cell suface. Provides biological markers at the surface.

Front 10

CAM proteins

Back 10

Intercellular junctions, that provide temporary binding sites that guide cell migration and other cell-to-cell interactions.

Front 11

What two types of membrane juctions would you expect to find between muscle cells of the heart?

Back 11

Desmosomes (anchoring junctions) to secure cardiac cells together as the heart works and gap junctions (communicating junctions) that allow ions to flow from cell to cell.

Front 12

Desmosomes

Back 12

Anchoring junctions.

Front 13

Tight Junction

Back 13

Impermeable junction

Front 14

Gap Junctions

Back 14

Front 15

What is the energy source for all types of diffusion?

Back 15

Diffusion is driven by the kinetic energy of the molecules.

Front 16

What determines the direction of any diffusion process?

Back 16

the relative concentration of the substance in different areas determines the directio of diffusion. diffusion occurs from high to low.

Front 17

What are the two types of facilitated diffusion and how do they differ?

Back 17

Channel and carrier mediated diffusion.
In channel mediated diffusion the diffusing substances moves through a membrane channel. In carrier mediated diffusion, the diffusing substance attaches to a membran (protein) carrier which moves it across teh membrane.

Front 18

Where is the extracellular fluid called intersitial fluid derived from?

Back 18

The blood. It is a rich soup that includes amino acids, sugars, fatty acids, vitamins, regulatory hormones and neurotransmitters, salts and waste products. Cell must extract what it needs from this mix.

Front 19

What two ways to substances move across membranes?

Back 19

Passive = no energy to happen.
Active = requires energy (ATP)

Front 20

Facilitated transport

Back 20

Front 21

Channels

Back 21

Transmembrane proteins transport ions or water through aqueous channes. Selective due to pore size, and the charges of AA lining the channel. Leakage channels stay open and allow ion and water to flux according to diffusion gradiant.

Front 22

What is more controllable, simple diffusion or facilitated diffusion?

Back 22

Facilitated diffusion because it is easier to control the membrane proteins than the membrane itself.

Front 23

Osmosis

Back 23

Diffusion of a solvent such as water through a selectively permeable membrane. Water is highly polar but is passes via osmosis through the lipid bilayer.

Front 24

Aquaporins (AQP)

Back 24

Water moves freely both ways through these water specific channels. Abundant in RBC's and kidney tubule cells.

Front 25

Is it the type or number of solute paritcles that matters in osmosis?

Back 25

The number because one molecule or one ion of solute displaces one water molecule.

Front 26

Osmolarity

Back 26

Total concentration of all solute particles in a solution.

Front 27

Hydrostatic Pressure

Back 27

Back pressure exerted by water against the membrane. Offsets osmotic pressure when water diffusing into the cell.

Front 28

Osmotic pressure

Back 28

Tendency of water to move into the cell by osmosis.

Front 29

Why doesn't hydrostatic pressure get very high in animal cells?

Back 29

Plasma membrane is flexible and will break.

Front 30

Tonicity

Back 30

the ability of a solution to change the shape or tone of cells by altering their internal water volume is called tonicity.

Front 31

Isotonic

Back 31

Same tonicity. 0.9 saline or D5W.

Front 32

Hypertonic solutions will what to a cell?

Back 32

Crenate or shrink it.

Front 33

What will distilled water do to a cell?

Back 33

It will lyse or burt it.

Front 34

Compare tonicity and osmolarity.

Back 34

Osmolarity is based solely on its total solute concentration. In contrast, its tonicity is basedon how the solution affects cell volume, which depends on solute conentration and solute permeability of the plasma membrane.

Front 35

Units of osmolarity

Back 35

osmol/L where 1 osmol is equal to 1 mole of nonionizing molecules.

Front 36

Why is a penetrating solute dangerous to a cell?

Back 36

It will penetrate the cell and bring water with it and burst the cell.

Front 37

In the capillaries...

Back 37

Hyrdostatic pressure pushes the water out, but large solutes pulls it back in again later.

Front 38

What is more selective, simple or facilitated diffusion?

Back 38

Facilitated diffusion.

Front 39

What is the energy source for simple diffusion, facilitated diffusion and osmosis?

Back 39

Kinetic energy.

Front 40

Primary active Transport

Back 40

ATP hydrolysis
Against concentration or electrochemical gradient. Across membrane by solute pump.
Ions (Na, K, Ca and others)

Front 41

Secondary active transport

Back 41

ATP maintained concentration gradient.
Cotransport. energy supplied indirectly by ion gradient created by primary active transport. SYMPORTERS move substances in same direction; ANTIPORTERS move substances in opposite directions. Movement of polar or charged solutes: AA (symporter into cell) Ca, H (out of cell by antiporter)

Front 42

Ratio of Na to K transport

Back 42

3 Na for 2K

Front 43

Carrier enzyme for Na K pump

Back 43

Na K ATPase

Front 44

Vesicular transport (requires ATP or in some cases GTP)

Back 44

Exocytosis
Endocytosis
Intracellular vesicular trafficking.

Front 45

Exocytosis

Back 45

Interior to exterior

Front 46

Endocytosis

Back 46

Exterior to interior.

Front 47

Transcytosis

Back 47

Into, across and then out of the cell.

Front 48

Vesicular trafficking

Back 48

moving substances from one area or organelle in the cell to another.

Front 49

Clathrin

Back 49

Protein found on the infolding portion of the plasma membrane in endocytosis.

Front 50

Endosome

Back 50

sorting vesicle

Front 51

Pinocytosis-fluid phase endocytosis or cell drinking.

Back 51

Nonselective way of an infolding palasma membrane to wurround small volume of fluid. Fuses with an endosome. Unlike phagocytosis, pinocytosis is a routine function.

Front 52

Receptor mediated endocytosis.

Back 52

Very selective endocytosis and transcytosis. External substance binds to membrane receptors. Intake of some hormones (insulin), cholesterol and iron. Diptheria and chlolera attach via this method.

Front 53

Potosis

Back 53

Specific to molecules using Caveolae "little caves". Smaller than the clathrin coated vesicles and use a different protein called aveolin.

Front 54

What are Caveolae associated with?

Back 54

Lipid rafts that are platofrms for G proteins. Involved in some form of cell signalling.

Front 55

Intracellular vesicular trafficking

Back 55

ATP is used. via coatomer coated vesicles. Vesicles pinch off from organelles and travel to other organelles almost all traffic between ER and Golgi.

Front 56

Exocytosis with v-SNARE and t-SNARE proteins.

Back 56

Front 57

What happens when the Na-K pump is phosphorylated? When K binds to the pump protein?

Back 57

Phosphorylation of the Na-K pump causes the pump protein to change shape and pump Na across the membrane. K binding to the pump protein triggers the release of phosphate and the pump returns to its original shape.

Front 58

As a cell grows, its plasma membrane expands. Does this membrane expansion involve endocytosis or exocytosis?

Back 58

The plasma membrane expands as a result of exocytosis.

Front 59

Phagocytic cells gather in the lungs, particularly in the lungs of smokers. What is the connection?

Back 59

Phagocytic cells engulf debris and a smoker's lungs would be laden with caron particles and other debris from smoke inhalation.

Front 60

What vesicular transport process allows a cell to take in cholesterol from the extracellular fluid?

Back 60

Cholesterol is taken in by receptor mediated endocytosis.

Front 61

Membrane potential.

Back 61

Voltage across a membrane.

Front 62

Voltage

Back 62

electrical PE resulting rom the separation of oppositely charged particles. In cells th ethe oppositel charged particles are ions and the barier that keeps them apart is the plasma membrane.

Front 63

What does the negative sign mean in the resting membrane potential -70mV?

Back 63

It means the inside fo the cell is negative compared to the outside. This voltage (or charge separation) exists only at the membrane. Total charge across the cell is neutral.

Front 64

Polarized

Back 64

State of plasma membrane of an unstimulated neuron or muscle cell in which the inside of the cell is relatively negative when compared to the outside.

Front 65

What ion mainly determines RMP?

Back 65

Gradient and differential permeability of K.

Front 66

Membrane is more permeable to Na or K?

Back 66

K.

Front 67

What is the cell RMP voltage?

Back 67

-70 mV.

Front 68

Without active transport what is the net flow of Na and K?

Back 68

K out and Na in.

Front 69

What event or process established the resting membrane potential?

Back 69

diffusion of ions, mainly K from the cell through leakage channels, established the RMP.

Front 70

The inside of the polarized plasma membrane is negative or positive relative to the outside?

Back 70

Negative

Front 71

Cell adhesion molecules (CAM) found on every cell. These sticky glycoprotis (cadherins and intergrins) act as:

Back 71

1] molecular velcro.
2]arms to haul themselves past one another.
3]SOS signals
4]Mechanical sensors of tension and stimulate sytnehsis or degradation of adhesive membrane junctions.
5] transmitters of intracellular signals that direct cell migrationn, proliferation and specialization.

Front 72

Membrane receptors: integral proteins and glycoproteins that serve as binding sites. Their functions are:

Back 72

CONTACT SIGNALING: touching for recognition.
CHEMICAL SIGNALING:use ligands on membrane receptors ie neurotransmitters.
G-protein-linked receptors.

Front 73

What is a common similarity to ligand binding when reactions to the binding is so different in various cell?

Back 73

When a ligan binds to a membrane receptor, the receptors structure changes and cell proeins are altered in some way.

Front 74

G-linked protein receptors

Back 74

Exert their effect indirectly throug a G protein with is a middleman to acitvation. Promotes formation of second messengers.

Front 75

What term is used to indicate signaling chemicals that bind to membrane receptors? Which type of membrane receptor is most important in driecting intracellular events by prmoting formation of second messengers?

Back 75

Ligands. g protein linked receptros direc intracelluar events by promoting formation of second messengers.

Front 76

where might you commonly find voltage gated channels?

Back 76

Neural and muscle tissues.

Front 77

What is the sequence of events in a G protein?

Back 77

Ligand (1st messanger)
receptor
G protein
Enzyme
2nd messanger (cAMP, iCa)

Front 78

Cytosol

Back 78

Vscous semitrasparent fluid in which th eother cytoplamic elements are suspended.

Front 79

Cytoplasmic organelles

Back 79

metabolic machiner of the cell. Each type carries out a specific function.

Front 80

Inclusions

Back 80

Chemical substance stham may or may not be present, depending on cell type. Glycogen granules in liver and muscle cells.

Front 81

Nonmembranous organelles

Back 81

Lack membranes such as cytoskeleton, centrioles and ribosomes.

Front 82

Mitochondria

Back 82

Twomembranes. Outer and inner. Inner has shelflike cristae. Performs cellular respiration to attach phosphate to ADP molecule have their own DNA, RNA and ribosomes and can reproduce themselves.

Front 83

Ribosomes

Back 83

Has two globular subunts that fit together like a body and cap of acorn. Site of protein synthesis. Ribosomal RNA.

Front 84

What are the two populations of ribosomes?

Back 84

Float free in cytoplasm
Attached to membranes forming rough endoplamic reticulum.

Front 85

How do the two populations of ribosomes split protein sythesis?

Back 85

Fee: soluble proteins that function in the cytosols as well as those for mitochondria and other organelles.
Membrane: sythesize proteins for incorporation into cell membranes of for export from the cell.

Front 86

Can ribosomes switch back between free and bound?

Back 86

Yes depending on the protein they are making.

Front 87

Endosplasmic Reticulum

Back 87

Continuous with the nuclear membrane and accounts for half of the cell's membrane. Sytem of interconnected tubes and parallel membranes enclosing fluid filled cisternae. Two varieties rough and smooth ER.

Front 88

Rough ER

Back 88

Makes proteins that are coated in coatomer coated vesicles for journey to Golgi. teh membrane factory

Front 89

Smooth ER

Back 89

Not involved in protein sythesis intstead:
Lipid metabolism, cholesterol sythesis,..
Synthesis of steroid based hromones
Absorption , synthesis of ffats
Detox of drugs
Breakdown of glycogen to form free glucose.

Front 90

What is the smooth ER called in muscle cells?

Back 90

Sarcoplasmic reticulum an it plays a role in clacium ion storage and release during muscle contraction.

Front 91

What organelle is the major site of ATP synthesis?

Back 91

Mitochondria

Front 92

What are three organelles involved in protein synthesis and how do these organelles interact in that process?

Back 92

Ribosomes are the sites of protein synthesis. Roug ER proides a site for ribosome attachment and its cisternae package in vesicles the proteins made on the ribosomes for transort to the Golgi apparatus. Golgi modifies and packages the prorteins it receive for various destinatoins in or out of the cell.

Front 93

How does the function of lysosomes compar to that of peroxisomes?

Back 93

Lysosomes digest foreign substances, deteriorating organelles or even the cell to prevent buildup of cellular debris. Peroxisomes detox harmful chemicals and neutralize free radicals.

Front 94

How are Microtubules and microfilaments related functionally?

Back 94

Both are involved in organelle movements within the cell and or movements of the cell as a whole.

Front 95

Of microfilaments, microtubules, or intermediate filaments, which is most importan in maintianing cell shape?

Back 95

Intermediate filaments are most important in cell shape.

Front 96

The major function of cilia is to move substances across the free cell surface. What is the major role of microvilli?

Back 96

Microvilli increase the cell's surface area ofr absorption or filtration.

Front 97

If a cell ejects or loses its nucleus, what is its fate and why?

Back 97

It will die because it will be unable to make proteins, and enzymes needed for reactions.

Front 98

What is the role of nucleoli?

Back 98

site of ribosome subunit manufacture.

Front 99

What is the importance of the histone proteins present in the nucleus?

Back 99

Allow DNA to be packed i a compact orderly way and play a role in gene regulation.

Front 100

If one of the strands of DA being replicated reads CGAATG, what will be the base sequenc of the corresponding DNA strand?

Back 100

GCTTAC

Front 101

During what phase of the cell cycle is DNA synthesized

Back 101

During the S phase

Front 102

29] Codons and anitcodons are both three base sequences. How do they differ?

Back 102

Codons are three base sequences in mRNA each of which specifies an amino acid. Anticodons are three base sequences in tRNA that are complementary to the codons specifiying the amino acid they transport to the ribosome during protein sythesis.

Front 103

30] How do the A, P, and E ribosomal sites differ functionally during protein synthesis?

Back 103

A site = entry site for tRNA at the ribosome.
P site = site where peptide bonds form between delivered amino acids.
E site = the tRNA exit site from the ribosome.

Front 104

31] What is the role of DNA in transcription?

Back 104

DNA provides the coded instructions (the template) for protein synthesis via mRNA synthesized on it.

Front 105

32] What is importance of ubiquitin in the life of a cell?

Back 105

Ubiquitin attaches to misfolded, damaged, or unneeded proteins, tagging them for destruction by proteasomes.

Front 106

33] What are two body fluids that inhabit the extracellular space and what role does each play in the body?

Back 106

Blood plasma is extracellular flulid that transports nutrients, gases, hormones, and other substanaces throughout the body.
Interstitial fluid is an important transport and dissolving medium.

Front 107

34] What is apoptosis and what is its importance in the body?

Back 107

Apoptosis is aprocess of programmed cell death which rids the body of cells that are stressed, damaged, old, or no longer needed.

Front 108

35] What is the wear and tear theory of aging?

Back 108

the wear and tear theory of Tging attributes aging to little chemical insults and free radicals which have cumulative detrimental effects.

Front 109

ANAPLASIA

Back 109

Abnomalities in cell structure and loss of differentiation; for example, cancer cells typically lose the appearance of parent cells and come to rsemble undifferenctiated or embryonic cells.

Front 110

DYSPLASIA

Back 110

A change in cell size, shape, or arrangement due to chronic irritation or inflammation (infections, etc.)

Front 111

HYPERTROPHY

Back 111

Growth of an organ or tissue due to an increase in the size of its cells. hpertrophy is a normal response of skeletal muscle cells when they are challenged to lift excessive weight; differes from hyperplasia, which is an increase in size due to an increase in cell number.

Front 112

LIPOSOMES

Back 112

Hollow microscopic sacs formed of phospholipids that can be filled with a variety of drugs. Serve as multipurpose vehicles for drugs, genetic material, and cosmetics.

Front 113

MUTATION

Back 113

A change in DNA base sequence that may lead to incorporation of incorrect amino acids in particular positions in the resulting protein; the affected protein may remain unimpaired or many function abnormally or not at all, leading to disease.

Front 114

NECROSIS

Back 114

Death of a cell or group of cells due to injury of disase. Acute injury causes the cells to swell and burst, and induces the inflammatory response. (This is uncontrolled cell death, in contrast to apoptosis or planned cell death).

Front 115

Golgi Apparatus

Back 115

Looks like hollow dinner plates stacked.
MAJOR FUNCTION: modify, concentrate, and package proteins and lipids made in the rough ER. Cis face (convex receiving side) trans face (concave shipping side) also packages enzymes into memgranous lysosomes that remain in the cell.