CH 1 & 3

Question 1

Define autophagy

Answer 1

Self eating

Question 2

What is Tay-Sachs and why does it occur?

Answer 2

Lipids build up in neurons due to an enzyme deficiency (not enough enzymes). This leads to disruption of neuron function.

Question 3

What is gout and why does it occur?

Answer 3

Urid acid accumulation destroys lysosomal membranes causing enzymes to leak out leading to inflammation. (Caused by too many enzymes)

Question 4

What are Peroxisomes

Answer 4

Vesicles filled with oxidative enzymes

Peroxisomes contain hydrogen peroxide (H2O2) that is used to detoxify compounds and fatty acids

Question 5

What is oxidation

Answer 5

A process that uses oxygen to remove hydrogen from a substrate

Question 6

What is catalase?

Answer 6

An enzyme that catalyzes peroxidative reactions to protect against excess hydrogen peroxide. (Turns 2H2O2 -> 2H2O + O2)

These are important b/c too much H2O2 in a cell would end up breaking down the cell itself

Question 7

Roles of microtubules and microfilaments

Answer 7

Structural support

Intracellular transport

Cell movement

Question 8

What is mechanotransduction and what part of the cell carry’s out mechanotransduction?

Answer 8

It is cellular processes that translate mechanical stimuli into biochemical signals.

It allows a cell to adapt to surroundings.

The cytoskeleton (microtubules and microfilaments) carry’s out mechanotransduction

Question 9

Where does translation occur?

Answer 9

At ribosomes … RNA code is translated to amino acids that ar ethen formed into proteins

Question 10

What does the golgi apparatus do?

Answer 10

Finishes proteins to pre-/pro- or active form

Proteins can then be used within the cell or transported to cell membrane for excretion by vesicles

Question 11

What allows for fluidity of the phospholipid belayer cell membrane?

Answer 11

The non polar hydrophobic center region because they are attracted to one another, but not bonded

This allows for damage repair

It also prevents free flow of charged ions/molecules through the membrane

Question 12

How does water pass through the plasma membrane?

Answer 12

Aquaporin channels

Question 13

What is an example of a disease caused by misfolding of membrane proteins?

Answer 13

Alzheimer’s disease - forms neurofibrillary tangles and plaques that results in changes in the membrane

Question 14

What is the role of CAM ( cell adhesion molecules )?

Answer 14

Keeps cells where they are supposed to be.
They attach to extra cellular matrix and also contribute to cell shape
They are essential to immunity as immunoglobulin superfamily CAMs

Question 15

What is a cytokine?

Answer 15

A regulatory protein that acts as a messenger molecule (cell-cell communication) and as growth factors

Question 16

What is a mitogen?

Answer 16

A regulatory protein. It is a molecule that stimulates mitosis by activating cytokines and cyclin dependent kinases

Question 17

Phases of mitosis

Answer 17

Prophase: chromosomes condense and are perceptible

Metaphase: chromosomes lines up in the middle

Anaphase: sister chromatids of each chromosome pull apart

Telophase: two nuclei form (each has the same number of chromosomes as the original cell)

Cytokinesis: pinching in of the cell membrane to form two different cells

Question 18

What are Cdks?

Answer 18

Cyclin dependent kinases

That are protein kinases (enzymes)

They regulate phosphorylation of intracellular proteins to manage timing within the cell cycle

Question 19

What occurs during oxidative phosphorylation?

Answer 19

ADP is converted into ATP using energy carried from GLUCOSE via NADH and FADH2.

Oxygen is used to neutralize the released H to form H2O to regulate pH in the mitochondria.

This is the main means of ATP production in eukaryotic cells

Question 20

Anabolism

Answer 20

Building

Using simple molecules to build complex ones

Requires the input of energy

Question 21

Catabolism

Answer 21

Breaking down

Breaking complex molecules into simpler ones

Releases energy as chemical bonds are broken

Question 22

How is energy stored?

Answer 22

Energy is stored as fat and glycogen.

ATP is constantly made as needed from food by metabolism. Energy is NOT stored as ATP

Question 23

Is cellular respiration catabolism or anabolism? And what is is?

Answer 23

Catabolism

Cellular respiration Breaks down molecules such as protein, fats and carbohydrates into amino acids, fatty acids and glucose

Is occurs mainly in the GI system and is absorbed from there into the blood

Question 24

Cations vs anions

Answer 24

Cations are positive;y charged ions

Anions are negatively charged ions

Ex: K+ Na+ Cl-

Question 25

Describe diffusion and its types

Answer 25

Movement of ions down a concentration gradient from greater to leaser concentration

Passive, does not require energy

Small and or lipid soluble ions diffuse more rapidly

Types: simple - moving directly across a membrane
Facilitated - moves through a pore or channel (sodium/potassium)

Question 26

Direction of osmosis

Answer 26

From high water (low solute) to low water (high solute)

Question 27

Osmolarity vs osmolality

Answer 27

Osmolarity = osmoles of solute/L of water
Used when fluid is outside of body

Osmolality = osmoles of solute/kg of water
Used when discussing fluid inside the body

Osmolality > Osmolarity in cells because the weight includes things other than water

Question 28

Endocytosis vs exocytosis

Answer 28

Endocytosis: movement into the cell
Activated by ligand binding to specific receptors
Phagocytosis = Endocytosis of large quantities
Pinocytosis = Endocytosis of small quantities

Exocytosis: movement out of the cell
Returns vesicle membrane to the cell membrane

Question 29

Endosomes

Answer 29

Vesicles that regulate ligand distribution and treatment throughout the cell

Question 30

Exosomes

Answer 30

Area of active research

Important in cell signaling, immune system activation, facilitation of cancer metastasis

Question 31

BHP & BCOP

Answer 31

Blood hydrostatic pressure = BHP
Pushes fluid out of blood into capillaries (higher at arterial end of capillary)

Blood colloid osmotic pressure = BCOP
Draws fluid out of tissues back into blood (higher at venous end of capillaries)

NFP = BHP - BCOP

Question 32

Edema

Answer 32

Excessive accumulation of fluid within tissue interstitial spaces

Edema within a body cavity may be called an effusion

Typically due to unequal fluid distribution rather than total body water excess

Results from capillary membrane damage resulting in altered permeability

Question 33

Hypertonicity vs hypotonicity

Answer 33

Hypertonicity- when ECF osmolality increases above ICF osmolality
Draws water out of cells

Hyoptonicity- when ECF decreases below ICF osmolality
Release water into cells (generate more hydrostatic pressure)

Question 34

Hypervolemia

Answer 34

Excess blood volume

It increases capillary hydrostatic pressure
It decreases blood on optic pressure due to protein dilution in expanded volume

Can be hypotonic or hypertonic (if extra blood volume is in ECF or ICF