Cells

Question 1

Water distribution: how much water is there in:

a) the ECF (extracellular fluid)?
b) the ICF (intracellular fluid)?

Answer 1

a) 14L [1/3 body water]
b) 28L [2/3 body water]

Question 2

Water distribution: how much water is there in the (ECF):

a) interstitial fluid
b) plasma

Answer 2

a) interstitial - 11L
b) plasma - 3L

Question 3

What is the predominant electrolyte(s) in the ICF?

Answer 3

K+

Question 4

What is the predominant electrolyte(s) in the ECF?

Answer 4

Na+, Cl-, HCO3-

Question 5

What is the definition of osmosis?

Answer 5

Movement of H2O across a partially permeable membrane from an area of high water potential to an area of low water potential.

Question 6

What is the definition of osmolarity?

Answer 6

The number of solute particles per L of fluid. (A high osmolarity has more solute particles per L).

Question 7

What is the definition of osmotic pressure?

Answer 7

The pressure that must be applied to a solution to prevent inward osmosis through a partially permeable membrane.

Question 8

What is the definition of oncotic pressure?

Answer 8

A form of osmotic pressure exerted by proteins, notably albumin, that tends to pull fluid into its solution.

Question 9

What is the function of rough ER?

Answer 9

Protein synthesis

Question 10

What is the function of smooth ER?

Answer 10

Lipid synthesis

Question 11

What is the function of the golgi apparatus?

Answer 11

Processes and modifies ER products.

Question 12

What is the cis face of the golgi apparatus?

Answer 12

The cis face is nearest the nucleus and receives ER vesicles.

Question 13

What does the medial Golgi do?

Answer 13

It modifies products by adding sugars forming oligosaccharides

Question 14

What does the trans face of the golgi do?

Answer 14

It sorts molecules into vesicles.

Question 15

What are the functions of vesicles?

Answer 15

Transports and stores materials. These are membrane bound organelles.

Question 16

What are desmosomes?

Answer 16

Intracellular junctions
Attach cells via the intermediate filaments.

Question 17

What are tight junctions?

Answer 17

Binds cells together to prevent leakage of molecules in between them.

Question 18

What is the function of gap junctions?

Answer 18

Conduct electrical signals.

Question 19

Name 4 molecules you’d find in a plasma membrane.

Answer 19

1. Cholesterol
2. Glycoproteins
3. Glycolipids
4. Integral proteins

Question 20

List 4 functions of a plasma membrane.

Answer 20

1. Physical boundary for the cell.
2. Regulates the movement of substances.
3. Has receptors for cell to cell signalling.
4. Attaches the cell to the external environment.

Question 21

What is type 1 collagen and example?

Answer 21

Makes up 90% of the bodies collagen
Eg: Bone, skin and teeth.

Question 22

What is type 2 collagen and example?

Answer 22

This type is found in elastic cartilage, which provides joint support
Eg: cartilage

Question 23

What is type 3 collagen and example?

Answer 23

This type is found in muscles, arteries and organs.
Eg: Arteries, liver, kidneys, spleen, uterus

Question 24

What is type 4 collagen and example?

Answer 24

This type is found in the layers of your skin.
Eg: Basement membranes

Question 25

What is an example of type 5 collagen?

Answer 25

Placenta

Question 26

Name 3 mechanisms by which a molecule can move across a plasma membrane.

Answer 26

1. Diffusion - movement down a concentration gradient. 2. Facilitated diffusion. 3. Active transport - uses ATP, against concentration gradient.

Question 27

Name 3 types of cell receptors.

Answer 27

1. Ion channel receptors. 2. G-protein coupled receptors. 3. Enzyme linked receptors.

Question 28

Name 3 ways in which we intake fluids.

Answer 28

1. Drink. 2. Food. 3. IV Fluids.

Question 29

Name 3 hormones involved in water homeostasis.

Answer 29

1. Aldosterone. 2. ADH - antidiuretic hormone. 3. ANP - atrial natriuretic peptide.

Question 30

What is oedema?

Answer 30

Excess H2O in the interstitial fluid.

Question 31

Name the 4 types of oedema.

Answer 31

1. Lymphatic. 2. Venous. 3. Hypoalbuminaemic. 4. Inflammatory.

Question 32

What is serous effusion?

Answer 32

Excess H2O in a body cavity.

Question 33

If a patient has diabetes insipidus and is not producing any ADH what is her blood and urine osmolality after 3 hours of water deprivation going to look like?

Answer 33

Blood osmolality would be high.

Question 34

Why is sodium doubled in the plasma osmolality equation?

Answer 34

To account for negatively charged ions.

Question 35

Give 3 examples of endocytosis.

Answer 35

1. Phagocytosis. 2. Pinocytosis. 3. Receptor mediated.

Question 36

What is hyponatremia?

Answer 36

Lower than normal level of sodium in the bloodstream.

Question 37

Electrolyte homeostasis: What is the cause(s) of hyponatremia and what are its risks?

Answer 37

Causes: Excess water due to IV fluids, diuretics. Risks: Over hydration - headache, confusion.

Question 38

What is hypernatremia?

Answer 38

Too high levels of sodium in the bloodstream.

Question 39

Electrolyte homeostasis: what is the cause(s) of hypernatremia? And what are the risks?

Answer 39

Cause - water deficit (poor intake, diabetes insipidus etc). Risks - Dehydration. (High sodium = low H2O which dehydrates the brain).

Question 40

What is hyperkalemia?

Answer 40

Too high potassium in the bloodstream.

Question 41

Electrolyte homeostasis: What is the cause(s) of hyperkalemia and what are its risks?

Answer 41

Causes: renal failure, acidosis, diuretic inhibitors. Risks: Cardiac arrest.

Question 42

What is hypokalemia?

Answer 42

Too low potassium in the bloodstream.

Question 43

Electrolyte homeostasis: What is the cause(s) of hypokalemia and what are its risks?

Answer 43

Causes: D+V, alkalosis, diuretics. Risks: weakness and dysrhythmia.

Question 44

What is hypercalcemia?

Answer 44

When calcium is too high in the bloodstream.

Question 45

Electrolyte homeostasis: What is the cause(s) of hypercalcemia and what are its risks?

Answer 45

Causes: hyperparathyroidism, Vit D toxicity, malignancy. Risks: renal stones and metastatic calcification.