Kidney function and failure Flashcards Preview

Biology B3 > Kidney function and failure > Flashcards

Flashcards in Kidney function and failure Deck (21)
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1
Q

What are the filtration units in the kidneys called?

A

Nephrons

2
Q

What happens in ultrafiltration? (2)
Squeeze
Membranes

A

High pressure is built up which squeezes water urea, ions and sugars out of the blood into the Bowman’s capsule
The membranes between the blood vessels and the Bowman’s capsules act like filters so big molecules like proteins and BCells are not squeezed out, they stay in the blood.

3
Q

Describe a single Nephron - a filtration unit in a kidney

  1. Blood in…
  2. The web, C
  3. The molecules
  4. Capillaries
  5. Blood off…
  6. Urine off…
A

The blood flows in through the renal artery
The artery splits up and looks like a web touching a backwards C called a Bowman’s capsule
The filtrated molecules flow down a winding yellow tubule
The winding yellow tube is tangled with a series of red tubes, the capillary network where reabsorbtion takes place
The capillaries rejoin to form the renal vein
The yellow tube meats the collecting duct which transports the urine into the bladder

4
Q
What is reabsorbed?
What happens through reabsorbtion?
S
I
W
A

Useful substances
All the sugar is reabsorbed, through active transport against the concentration gradient
Sufficient ions are reabsorbed, excess ions are not, through active transport
Sufficient water is reabsorbed

5
Q

How are the excess products wasted from the filtration in the kidneys?

A

Urea etc continue out of the Nephron and down into the ureter into the bladder as urine

6
Q

Each kidney contains about ….Nephrons

A

1 million

7
Q

What are the two treatments for kidney failure to keep people alive?

A

Regular dialysis treatment where machines do the jobs of the kidneysor a kidney transplant

8
Q

What do the kidneys do?

A

Remove waste substances from the blood

9
Q

What happens if the kidneys don’t work properly?

A

Waste substances build up in the blood and you lose your ability to control the ion and water levels in the blood, this eventually results in death.

10
Q

Where are the problems you can get with kidney failure?

A

Heart, bones, nervous system, mouth etc

11
Q

What do dialysis machines do?

A

Filter the blood

12
Q

Why does dialysis have to be done regularly? (2)

A

To keep the concentrations of dissolved substances in the blood at normal levels and to remove waste substances

13
Q
What happens in a dialysis machine?
Flow
P to what?
In the dialysis fluid
This means that...
So only... using what transport?
A

The person’s blood flows alongside a SELECTIVELY permeable barrier surrounded by dialysis fluid.
It is permeable to ions, waste substances but not big molecules like proteins, just like the kidney membrane
The dialysis fluid has the same concentration of dissolved ions and glucose as healthy blood.
This means the useful dissolved ions and glucose won’t be lost from the blood during dialysis.
This means only waste substances (urea) and excess ions and water diffuse across the barrier

14
Q

How often and for how long to dialysis patients need treatment?

A

Three times a week for 3-4 hours

15
Q

What can dialysis cause?

A

Blood clots or infections

16
Q

What is the problem with transplanted organs?

A

They are rejected by the body

17
Q

What is the only cure for kidney disease?

A

Kidney transplant

18
Q

What are healthy kidneys usually transplanted from?

Or?

A

People who have died suddenly, car accidents por ejemplo, who have an organ donor card or are on the register, provided their relatives give the ‘go ahead’.
From people who have two healthy ones and volunteer

19
Q

What are the kidneys rejected by?

How and with what?

A

The patient’s immune system

The foreign antigens on the donor kidney are attacked by the patient’s antibodies

20
Q

How are rejections to kidneys prevented?
The same …. What is this based on?
What are used to stop what?

A

A donor with the same tissue type that closely matches is used. The tissue type is based on antigens, the proteins on the surfaces of most cells.
Drugs are used to treat the patient to supress the immune system so that it won’t attack the transplant

21
Q

What are the negatives for dialysis …

and transplants?

A

.. the machines are expensive for the NHS, the process is time consuming and boring and not a plesent experience
Transplants are cheaper and can put an end to the hours spent on the dialysis machines but the waiting lists are long. If you do get a similar tissue type there is still a chance of it being rejected.
Taking the immunosupressents makes the patient vulnerable to illness.