Homeostasis of the body

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Slide 22

Time

Glucose

Concentration

Meal eaten

Insulin is produced and glucose levels fall to normal again.

Glucose levels rise after a meal.

Normal

Slide 23

Time

Glucose

Concentration

Meal eaten

Insulin is not produced so glucose levels stay high

Glucose levels rise after a meal.

Diabetic

Slide 24

The glucose in the blood increases.

Glycogen

Insulin

Glucose in the blood

But there is no insulin to convert it into glycogen.

Glucose concentration rises to dangerous levels.

Slide 25

Controlling water levels

The control of water levels is carried out by the KIDNEYS.

It is closely linked to the excretion of urea.

Urea is a waste product that is made when the LIVER breaks down proteins that are not needed by the body.

Urea contains the element Nitrogen.

Slide 26

The kidneys

The kidneys “clean” the blood of waste products and control how much water is kept in the body. The waste products and water make up urine which is excreted via the ureter.

“Dirty” blood enters the kidney through the renal artery. Then, several things happen to clean the blood .

Slide 27

Blood enters the tubule area in a capillary.

The capillary forms a small “knot” near the kidney tubule.

The blood is filtered so all the small particles go into the tubule.

The capillary then carries on to run next to the tubule.

1. Filtration

Slide 28

The kidney tubule now contains lots of blood components including:

Glucose:

Ions:

Water:

Urea:

Slide 29

2. Reabsorb sugar

The body needs to have sugar in the blood for cells to use in respiration. So all the sugar is reabsorbed back into the capillary.

Slide 30

2. Reabsorb sugar

The body needs to have sugar in the blood for cells to use in respiration. So all the sugar is reabsorbed back into the capillary.

Slide 31

3. Reabsorb water

Water and ions are the next to be absorbed. It depends on how much is needed by the body.

Slide 32