Biological Control and Homeostasis Flashcards
Symptoms
What happens if there is a change in our environment?
- Pain
- Discomfort
- disease/sickness
- damage injury
- death
What percentage of the human body is water?
60%
What are the two types of fluid that make up the water in the human body?
think cells
think fluid
Extra Cellular and Intracellular Fluid
What percentage + litres of water is made up of extra cellular fluid?
35%= 14litres
think salt and sweat
How is the volume of extracellular fluid determined?
The volume of extracellular fluid is determined by:
The BALANCE of sodium intake + renal excretion of sodium
fluid. two types.
What is the environment that all cells live in within the body?
All cells live in the extracellular fluid (ECF) environment.
What factor primarily influences changes in extracellular fluid volume under NORMAL conditions?
Variations in salt (sodium) intake
Explain the relationship between salt intake and renal salt excretion in maintaining Extracellular Fluid volume
Under NORMAL conditions:
An increase in salt intake leads to an increase in renal salt excretion, maintaining the ECF volume within NARROW limits.
A decrease in salt intake leads to a reduction in renal excretion to maintain balance.
Why is it important for the body to maintain the ECF volume within NARROW limits?
Crucial for ensuring homeostasis, as it affects the fluid balance, blood pressure, and overall functioning of cells and tissues.
What role does the kidney play in regulating the ECF volume when there is an INCREASE in salt intake?
kidneys excrete more sodium through urine, helping to prevent excessive accumulation of fluid and maintain ECF volume
What happens to ECF volume when renal excretion of sodium is reduced, assuming salt intake remains constant?
ECF volume will increase, potentially leading to fluid retention and associated issues like high blood pressure.
What separates the intracellular fluid (ICF) from the extracellular fluid (ECF)?
The cell membrane, which is semipermeable
What are the main components of the intracellular fluid (ICF)?
there are 3 answers
- Water
- Electrolytes
- Proteins
P-P-M
List the most common electrolytes found within the intracellular fluid (ICF).
there are 3 answers
- Potassium
- Phosphate
- Magnesium
What is the role of the cell membrane in relation to the movement of substances between the ICF and ECF?
The cell membrane is semi-permeable
The semipermeable cell membrane controls the movement of substances between the ICF and ECF allowing selective passage of certain ions and water to maintain balance
ossy osbourne
Why is the concentration of electrolytes important for maintaining water balance within the cell?
The concentration of electrolytes influences osmotic pressure - regulates the movement of water into and out of the cell - helping to maintain proper cell volume and function.
How does the concentration of electrolytes in the intracellular fluid affect water volume?
Changes in electrolyte concentration can alter osmotic gradients = water to move into or out of the cell= affecting the volume of water within the cell.
ossy osbourne
What is an example of a homeostatic mechanism involving the concentration of electrolytes and water volume?
osmosis
where the body regulates the concentration of electrolytes to maintain proper water balance within cells, ensuring stable cell function and volume.
What is homeostasis?
The tendency to resist change in order to maintain a stable, relatively constant internal environment
individual ‘set’ points change day to day
Which syststem IS NOT involved in homeostasis?
reproductive system
What does the integumentary system consist of?
consisting primarily of the skin
also:
* hair, nails, glands (e.g., sweat and oil glands)
* sensory receptors
4 points
How does the integumentary system contribute to homeostasis?
- PROTECTS body by acting as barrier from external threats such as pathogens, UV radiation, chemicals, and physical injuries.
- REGULATES body temperature through sweating and blood vessel dilation or constriction
- EXCRETION of waste products like salt, water, and urea.
- KEY SENSOR of external stimuli
How does the muscular system contribute to homeostasis?
- ALLOWS MOVEMENT through skeletal muscles, smooth muscles in blood vessels help regulate blood flow and blood pressure by vasoconstriction or vasodilation and cardiac muscles pump blood to deliver oxygen and remove waste products.
- HEAT GENERATION through muscle contractions essential for maintaining body temperature. E.g. shivering (involuntary muscle contractions) to generate heat and maintain a stable core temperature.
- RESPIRATION through skeletal muscles, such as the diaphragm and intercostal muscles, are essential for breathing= adequate oxygen intake and carbon dioxide removal crucial for maintaining the body’s pH balance.
What are the two major control systems of homeostasis?
Nervous and Endocrine system
