The kidneys

What are the 3 jobs for the kidneys?

Remove waste product, regulate ion levels, regulate h2O conc in blood.

Where is urea made?

liver

what is urea

A waste product formed in the liver. The blood transports it to the kidneys where it is removed.

what is deamination?

removal of an amino group

what happens to our cells if we drink too much water?

Too much water diffuses into the cell and can cause them to burst

When do we lose ions

when we sweat

Which part of the brain detects the concentration of water?

the Hypothalamus

What happens if the water conc in the blood is too low?

The hypothalamus sends a signal to the pituitary gland which sends a signal to release more ADH (Antidiuretic Hormone). This causes the Kidneys to reabsorb more H2O into blood. This causes us to produce less urine.

What happens if the water conc in the blood is too high?

The hypothalamus does NOT send a signal to the pituitary gland which causes there to be little to no ADH released. This means that the Kidneys will absorb less H2O into the blood, causing there to be more urine.

What is the ADH cycle an example of?

negative feedback loop

What are tubules?

small tubes in the kidneys

What do the tubules do?

Absorb small molecules (everything apart from cells and proteins)

What happens after absorption?

reabsorption

What do the tubules reabsorb?

almost all glucose and amino acids, some water and ions and NO urea

What is the reabsorption called?

selective reabsorption

What is a nephron

structural and functional unit of the kidney

What does the nephron consist of

glomerulus (blood vessels) and renal tubule

what does the renal tubule do?

converts filtrate into urine

How does blood enter the kidney

renal artery

How does blood leave the kidney

renal vein

What's the first step to making urine? explain

Filtration. Some liquid part of the blood starts at the glomerulus and then is forced to the bowman's capsule (the start of the tubule) where only small substances can pass through.

What is the second step to making urine? explain?

The liquid travels through the tubules whilst they absorb everything they want, into the blood. (glucose, water, amino acids, ions)

What is step three? the Final step.

After the kidney absorbs everything they need and the liquid passes through the whole nephron, it then ends up at the collecting duct where the waste product is collected. It then gets passed through the ureters to the bladder and then out through the urethra.

What are the two treatments for Kidney failure?

dialysis and kidney transplants

What are the consequences of kidney failure?

Poor regulation of ion and water levels.

Increase (build up) in waste products like urea

What is dialysis?

the clinical purification of blood by dialysis, as a substitute for the normal function of the kidney.

How does Dialysis work?

Blood is passed through a dialysis machine, containing a partially permeable membrane, with dialysis fluid on the other side of the membrane. Urea, as well as excess water and mineral ions diffuse out of the blood or vice versa. The cleaned blood is then returned to the patient.

What are the disadvantages of dialysis

Time consuming: have to go hospital multiple times 2-3 and be attached to a machine for 4-6 hours.

Blood clots

infection

Expensive

lifelong treatment

Dialysis Fluid has to be replaced constantly.

What is dialysis fluid?

Same concentration of dissolved ions and glucose as healthy blood

What are the advantages of dialysis?

Greatly reduced levels of urea

correct water and ion balance is maintained

allows a person with kidney failure to maintain their health

Able to survive whilst waiting for a doner.

What must a patient take after a kidney transplant?

Immunosuppressant drugs for life

What is a disadvantage of a kidney transplant related to infection?

Increased chance of infection

What is a major issue regarding kidney availability for transplants?

Shortage of donors

How long may a transplanted kidney last?

8-9 years

What risks are associated with the kidney transplant operation?

Operation carries risks

What is a potential outcome regarding the body's response to a transplanted kidney?

Could be rejected by the body

What is required for a successful kidney transplant in terms of donor and recipient?

Must be closely matched

What is a consequence of needing a close match for kidney transplants?

Patients have to wait for a long time

What's the advantages of kidney transplants?

cheaper than dialysis.