Week 6: Body Water Balance and Hydration Flashcards

1
Q

How much of our body is made up of water?

A

60-70%

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

What is our typical survival time without drinking water?

A

100 hours

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

What is the typical rate of sweat during exercise per hour?

A

1-2 litres per hour

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

What does total body water include?

A

Fluid that occupies intra-cellular and extra-cellular space roughly equals 60% of body mass

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

What does intra-cellular fluid volume include?

A

Fluid within tissue cells roughly equals 40% of body mass

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

Which enzyme electrolyte has the greatest concentration in plasma?

A

Sodium

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

Name the two main hormones that help regulate plasma osmolatity

A

Antidiuretic hormone

Aldosterone

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

What plasma osmolality reading is classified as euhydration?

A

285-290 mOsmol per kg

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

What are the organic substances that make up body fluids?

A
Glucose
Amino acids
Fatty acids
Hormones
Enzymes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the inorganic substances that make up body fluids?

A
Sodium
Potassium
Calcium
Magnesium
Chloride
Phosphate
Sulphate
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What effect the distribution of body water?

A

The relative concentration of the solutes within the blood

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

What is body water balance?

A

When the volume of water intake is equal to the volume that is lost

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

How do we intake water?

A

Food
Fluids
Metabolism

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

How is water lost?

A

Urine
Faeces
Skin
Lungs

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

What is total body water (TBW)?

A

Fluid that occupies intra-cellular and extra spaces

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

What is intra cellular fluid volume (ICFV)?

A

Fluid within tissue cells

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

What is extra cellular volume (ECV)?

A

All fluids outside of cells

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

What is interstitial fluid volume (IFV)?

A

Located spaces between tissue cells

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

What is plasma volume (PV)?

A

Liquid portion of blood

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

What separates the intracellular fluid and the interstitial fluid?

A

Plasma membrane

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

What type of membrane is the plasma membrane?

A

Semi-permeable

22
Q

What separates the interstitial fluid and the plasma?

A

The vascular wall

23
Q

What type of membrane is the vascular wall?

A

Semi-permeable

24
Q

How does water travel across the semi-permeable membrane?

A

Via osmosis

25
What happens in euhydration?
Normal body water level | The osmolarity of the intracellular and extracellular fluids are the same
26
What happens in hypohydration?
The fluid around the cell has a higher solute concentration, causing water to diffuse out of the cell
27
What happens in hyperhydration?
The fluid around the cell has a lower solute concentration therefore water diffuses into the cell
28
What are the four general functions of electrolytes?
Control osmosis between body fluid compartments Help maintain the acid-base balance Carry electrical current Serve as cofactors
29
What is the most abundant ion in the extracellular fluid?
Sodium
30
What does sodium help control?
Our body water status
31
What is fluid balance critical for?
Metabolic, cardiac and thermoregulatory funciton
32
How is fluid balance controlled?
The endocrine system
33
What are the two primary hormones that regulate water balance?
``` Antidiuretic hormone (ADH)/ arginine vasopressin Aldosterone ```
34
Where is the antidiuretic hormone (ADH) released?
The posterior pituitary glands
35
What stimulates secretion of antidiuetic hormone?
Haemoconcentraction (too much salt) Increase in plasma osmolality Decrease in plasma volume
36
What does antidiuretic hormone (ADH) do and why?
Promotes water retention in the kidney in an effect to dilute plasma electrolyte concentration back to normal
37
Where is aldosterone released from?
The adrenal cortex
38
What stimulates aldosterone secretion?
Decrease in plasma sodium Decrease in blood volume Decrease in pressure Increase in plasma potassium concentration
39
What type of hormone is aldosterone?
A mineralcorticoid hormone
40
What does aldosterone do and why?
Promotes renal reabsorption of sodium causing increased fluid retention
41
When is atrial natriuretic peptide (ANP) released?
Atrial distension Endothelin Sympathetic stimulation
42
What does atrial natriuretic peptide (ANP) do?
Reduces blood pressure Reduces blood volume Causes vasodilation
43
Which electrolyte has the greatest conc in plasma?
Sodium
44
Name the two main hormones that help regulate plasma osmolality?
Antidiuretic hormone | Aldosterone
45
What plasma osmolality reading is classified as euhydrated, including units?
295 mOsmol/kg
46
What are the cellular consequences of dehydration?
Loss of solutes/reduced blood volume Causes change in osmotic pressure Cells lose water and shrink due to osmosis
47
How does sweating effect blood volume and therefore plasma volume?
Decreases blood volume due to a decreased plasma volume
48
What are the cardiovascular consequences of dehydration?
Decreased stroke volume Decreased cardiac output (less blood pumped) Decreased blood pressure (less muscle blood flow)
49
Why do we become dehydrated during exercise?
Sweating
50
Why does dehydration impair endurance exercise performance?
``` Decreased: Plasma volume Blood volume End diastolic volume Stroke volume Cardiac output Vo2 max Increased anaerobic metabolism ```
51
Why does dehydration impair game performance?
Endurance performance impairments plus motor and cognitive impairments