WEEK 2 - MOVEMENT OF MOLECULES

Question 1

TRUE or FALSE
ECF makes up 40% of the body’s weight in water

Answer 1

FALSE. ICF makes up 40% of the body’s weight in water and ECF makes up 20%

Question 2

Name 2 components of ECF and describe them

Answer 2

Interstitial fluid (IF) and Plasma.
IF - makes up 80% of ECF (12L Volume)
Plasma - makes up 20% of ECF (3L Volume)

Question 3

Name the components of total body of water and mention their percentages

Answer 3

Total body of water 60% of body weight (40L)
ICF - 40% of body weight (25L)
ECF = Interstitial fluid (IF) + Plasma
ECF - 20% of body weight (15L)
IF - 80% of ECF (12L)
Plasma - 20% of ECF (3L)

Question 4

What is WATER’s role in movement of molecules?

Answer 4

UNIVERSAL SOLVENT (what something is dissolved in)

Question 5

SOLUTE

Answer 5

what is dissolved in fluid

Question 6

Osmosis

Answer 6

Movement of water from low solute to high solute concentration

Question 7

Diffusion

Answer 7

Solute travels from area of high concentration to low concentration

Question 8

Describe what would happen to a cell in a hypertonic, isotonic and hypotonic solution if ICF is 300 mOsm

Answer 8

Hypertonic = ~(ECF is 400 mOsm)
water from ICF moves from low solute to high solute concentration, thus moves OUT of the ICF, the cell shrinks = crenation

Isotonic = ~(ECF is 300 mOsm)
No change occurs as ICF and ECF are balanced

Hypotonic = ~(ECF is 200 mOsm)
water from ECF moves from low solute to high solute concentration, thus moving INTO the cell, the cell swells and can burst = lysis

Question 9

ECF vs ICF concentration in body

Answer 9

Na+ = LOWER ICF/ HIGHER ECF
K+ = HIGHER ICF/ LOWER ECF
Cl- = LOWER ICF/ HIGHER ECF
GLUCOSE = LOWER ICF/ HIGHER ECF
PROTEIN = HIGHER ICF/ LOWER ECF

Question 10

VESICULAR TRANSPORT

Answer 10

Transport via vesicles (endocytosis and exocytosis)

Question 11

What is Osmolarity?

Answer 11

The number of osmoles of solute per litre of solution

Question 12

What is an osmole?

Answer 12

A unit of measurement that describes the number of moles of solute particles that are dissolved in water.

Question 13

What is the equation for Osmolarity?

Answer 13

number of particles in solution x concentration = Osmolarity
e.g. 1 x 100mM = 100 mOsm glucose
2 (1 Na +1 Cl) x 100 mM = 200 mOsm NaCl
3 (1Ca + 2 Cl) x 100 mM = 300 mOsm CaCl2