Anatomy And Physiology 4 - Part 2

Front 1

What is fluid balance?

Back 1

The homeostasis of fluids. It ensures the total amount of fluid in the body is normal and it remains constant.

Front 2

What is electrolyte balance?

Back 2

Usually refers to the salt balance in the body.

Front 3

What is body fluid balance?

Back 3

Water makes up 50%-60% of adult body weight. Water occupies 3 main locations in the body called fluid compartments.

Front 4

What are the 3 fluid compartments water occupies?

Back 4

- Intracellular Fluid

- Interstitial Fluid (extracellular fluid)

- Plasma Extracellular Fluid

Front 5

Where is intracellular fluid?

Back 5

Lies inside cells (largest volume of water is held here.)

Front 6

Where is interstitial fluid located?

Back 6

In the microscopic spaces between cells.

Front 7

Where is plasma extracellular fluid located?

Back 7

It's the liquid in the blood.

Front 8

Who has lower water content and why, fat or skinny people?

Back 8

Fat because fat is almost water free.

Front 9

In newborns, water accounts for what percentage of total body weight?

Back 9

75%. The high level accounts for their dewy skin.

Front 10

The average adult male, how much of their body weight is water? Average female?

Back 10

Male: 60%

Female: 50%

The difference has to do with the percentage of body fat.

Front 11

As long as input and output are the same, total amount of water in the body shouldn't change. At what ratio do we recieve liquids from drinks, food and cellular metabolism?

Back 11

Liquids: 60%

Food: 30%

Cellular metabolism: 10%

Front 12

Vital Property of Water: High heat capacity

Back 12

Water can absorb and release large amounts of heat before its temperature will change appreciable. Therefore the water content in the body helps to maintain temperatures no matter the temperature outside the body.

Front 13

Vital Property of Water: Polarity/solvent properties

Back 13

Because of water's polarity, water is an excellent solvent. All chemical reactions that occur in the body depend on the water's solvent properties. Nutrients, respiratory gases and waste can dissolve in water; water can act as a transport and exchange medium in the body. Specialized molecules that lubricate the body also use water as their solvent. ex: mucus and saliva.

Front 14

Vital Property of Water: Chemical reactivity

Back 14

Water is important in some types of chemical reactions - hydrolysis reactions.

Front 15

Vital Property of Water: Cushioning

Back 15

Water has a protective function. CSF water forms a cushion around the brain and spinal cord. Also amniotic fluid is a cushion.

Front 16

What causes dry mouth?

Back 16

There is a rise in osmotic pressure which causes less fluid to leave the blood stream. Because salivary glands obtain water they require from the bloodstream, less saliva is produced.

Front 17

How does the damping of thirst begin?

Back 17

The mucosa in the mouth and throat are moistened which signals that inhibit the thirst centre.

Front 18

The regulation of water output is conducted by which 4 organs?

Back 18

- Kidney

- Lungs (Water exits the lungs in expired air)

- Skin (Perspiration)

- Intestine (Feces)

Front 19

How do the kidneys regulate water output?

Back 19

The kidneys are the organs that affect the output of fluid the most. They control fluid balance by changing the volume of urine excreted to match changes in the volume of fluid intake. The more fluid we drink, the more urine one excretes.

Front 20

There are 4 major roles the kidney have in the body:

Back 20

1) Excretion of nitrogen containing waste.

2) Maintaing water balance in blood.

3) Maintaining electrolytes balance of blood.

4) Ensuring proper pH balance in blood.

Front 21

Dehydration:

Back 21

When intestinal fluid volume decreases, intracellular fluid and plasma volume decrease below normal levels. This can result form too little fluid intake or too much fluid output.

Front 22

Over Hydration:

Back 22

When total body fluid volume is larger than normal, the intestinal fluid volume increases, then the intracellular fluid increases and plasma volume volume increases. This can result in extra stress on the heart and can deprive the body of essential electrolytes.

Front 23

Capillary B/P is a water pushing force. Where does it push fluid?

Back 23

Out of the capillaries and into interstitial fluid space (called hydrostatic pressure.)

Front 24

The concentration of what in blood plasma, decides how much water moves into blood from interstitial fluid (called Osmotic Pressure?)

Back 24

Proteins present

Front 25

___________ acts as a water-pulling or water-holding force.

Back 25

Plasma Proteins

Front 26

What can hold water in the blood and also pull water into the blood from the interstitial fluid?

Back 26

Blood Proteins

Front 27

Non-electrolytes:

Back 27

Compounds that do not break up in water solution. These are mostly organic molecules like glucose, lipids, creatine and urea.

Front 28

Electrolytes:

Back 28

Compounds that break up in water solution into separate particles (ions.) They can conduct an electrical current. These include inorganic salts, proteins and inorganic and organic acids and bases.

Front 29

Electrolytes have an important nutrient and regulatory role in the body.

Back 29

- Hemoglobin production

- Synthesis of Thyroid

- Nerve conduction

- Muscle contraction

Front 30

Each fluid compartment has a distinctive pattern of electrolytes - For interstitial fluid:

Back 30

Mostly contains high levels of sodium and chloride and small amounts of potassium.

Front 31

Each fluid compartment has a distinctive pattern of electrolytes - For blood plasma:

Back 31

Has high protein content. It also contains lots of sodium. Chloride is present but there is less chloride in plasma than interstitial fluid.

Front 32

Each fluid compartment has a distinctive pattern of electrolytes - For intracellular fluid:

Back 32

Has small amounts of sodium and chloride but lots of potassium phosphate and some magnesium.

Front 33

What is the mixing of body fluids regulated by?

Back 33

Osmotic and/or hydrostatic pressure.

Watermoves freely between compartments along osmotic gradients but solutes depend on active transport to move between compartments.

Front 34

Exchange between plasma and interstitial fluid occurs where?

Back 34

Across the capillary membranes.

Nearly protein-free plasma is forced out of the bloodstream into the interstitial space by hydrostatic pressure of blood. This filtered fluid is almost completely reabsorbed into the bloodstream in response to the osmotic pressure of plasma proteins.

Front 35

Any small leakage of this filtered fluid in the capillary membrane is picked up by the _______________ and reabsorbed back into the bloodstream.

Back 35

lymphatic vessel

Front 36

What is more selective, capillary membranes or cellular membranes.

Back 36

Cellular membranes

Front 37

Summarize the movement of fluids among compartments:

Back 37

Movement of nutrients, respiration gases and waste are typically unidirectional. Ex: Glucose and oxygen move into cell and metabolic waste moves out of the cell into interstitial fluid space, then into the blood capillary.

Front 38

Of all fluids, which circulates throughout the body and links the external and internal environment?

Back 38

Plasma

Front 39

Where do plasma exchanges occur?

Back 39

The lungs, GI tract and kidneys. These exchanges can alter plasma composition, therefore altering the other two fluid compartments, restoring balance.