Homeostasis Flashcards
What is homeostasis?
Controlling the internal conditions.
Name the conditions that need to be monitored.
Water levels. Sugar levels. Ion content. Temperature. Sugar control.
What waste products need to be removed from the body?
Urea and carbon Dioxide.
How is carbon dioxide produced?
In every living cell through respiration.
How does the body remove Co2?
Removed through breathing in the lungs.
Where is Urea produced?
When Amino Acids are broken down in the liver.
Where is Urine produced?
The Liver.
What organ removes urea?
The kidneys put it into Urine.
Why does water balance need to be maintained?
If it isn’t then water may move into or out if the cells and damage then.
How does the body respond to too much water?
By sweating and through Urea.
What do the kidneys control?
They control the water and ion content of blood.
What removes urea from the blood?
The kidneys remove Urea from the blood.
What artery supplies the Kidneys with blood?
The renal artery.
What are the steps in a healthy kidney making Urine?
Filtering the blood.
Reabsorbing all the sugar.
Reabsorbing all the ions needed any the body.
Reabsorbing the amount of water the body needs and then releasing urine.
How do the kidneys filter blood?
The blood enters through the renal artery and spreads into capillaries. The liquid leaves into a tubule and leaves behind the cells and large molecules in the blood.
What is the Reabsorbing of sugar and ions like in terms of concentration gradients?
They move against a concentration gradient back into the blood.
What is urine made of?
Excess products like water, ions and Urea.
How can kidney failure be treated?
Dialysis.
Transplants.
How does a dialysis machine work?
It is attached so that the persons blood flows through it. It then flows through partially permeable membranes. The membranes are surrounded by fluid, with the same concentration. This makes the excess ions leave or places some in.
What is the concentration in Dialysis fluid like?
It has the same concentration of useful substances as the blood.
How is having the concentration of dialysis fluid important?
It stops glucose and mineral ions being taken from the blood.
What is the movement of particles in Dialysis called?
Diffusion.
Where does Urea go in Dialysis?
From the blood to the Dialysis fluid.
How do doctors avoid the body rejecting a kidney transplant?
By using a donor with a similar tissue type.
Treating them with drugs that stop White Blood Cells.
What are advantages of Dialysis?
There is no major surgery and waiting lists.
What are the disadvantages of dialysis?
Diet needs to be controlled and restricts normal life because it takes so long.
What are the benefits of Kidney transplants over dialysis?
They can have a relatively normal life and do not need to restrict their diets.
What are the disadvantages if transplants?
Major surgery is dangerous and the body may reject the organ. Immunosuppressant drugs need to be taken for life.
What temperature is best for enzymes in the body?
37 degrees Celsius
Where is body temperature controlled and regulated?
The Thermoregulatory centre in the brain.
How does the Thermoregulatory centre know temperature?
It has receptors that are sensitive to the temperature of the blood flowing through the brain.
How do we know skin temperature?
There are receptors in our skin that send impulses to the brain.
What does the body do if temperature is too high?
The blood vessels in the capillaries dilate near the skin and the body sweats.
How the dilating capillaries change body temperature?
It means more blood flows near the skin, increasing the area that is losing heat from the blood.
How does sweat cool the body?
Evaporation has a cooling effect.
How does the body respond if the temperature is too low?
The bold vessels supplying the skin get narrower and muscles shiver.
How does shivering affect body temperature?
Their contraction needs respiration and it releases some energy as heat.
How does the capillaries getting narrower decrease heat loss?
It means less blood flows through the capillaries.
