ORGANS IN THE BODY - KIDNEY

Question 1

removes waste from the body to maintain balance (homeostasis).

Answer 1

excretory system

Question 2

Waste is eliminated in three main ways:

Answer 2

1. Through the skin - as sweat
2. Through the lungs - as exhaled carbon dioxide
3. Through the urinary system - as urine

Question 3

Main Organs of the Urinary System

Answer 3

Kidneys
Ureters
Bladder
Urethra

Question 4

filter the blood and make urine.

Answer 4

Kidneys

Question 5

tubes that carry urine from the kidneys to the bladder.

Answer 5

Ureters

Question 6

stores urine.

Answer 6

Bladder

Question 7

the tube where urine comes out of the body.

Answer 7

Urethra

Question 8

Structure of the Kidney

Each kidney is a bean-shaped organ located below the liver. Inside, there are three regions:

 Renal cortex (outerlayer) - contains over a million nephrons, the functional units that filter blood.

 Renal medulla (middle layer)

 Renal pelvis (inner area) - collects urine and connects to the ureter

Question 9

HOW BLOOD IS FILTERED? (6 STEPS)

1. Blood Enters the Kidneys
2. Filtration Begins in the Glomerulus
3. Reabsorption in the Tubules
4. Secretion
5. Urine Formation
6. Cleaned blood

Question 10

HOW BLOOD IS FILTERED?

1. Blood Enters the Kidneys
   -Blood flows into the kidneys through the renal arteries.
2. Filtration Begins in the Glomerulus
   -Blood enter GLOMERULURUS a tiny bundle of capillaries called NEPHRONS. Each kidney contains about 1 million nephrons, which are the actual filtering units.The pressure in the glomerulus forces waste products (like urea) out of the blood into a capsule called Bowman’s capsule.
3. Reabsorption in the Tubules
   -Here, the body reabsorbs useful stuff like glucose, some salts, and most of the water back into the bloodstream.
4. Secretion
   -Additional waste and excess ions are secreted from the blood into the tubule to make sure the body gets rid of what it doesn’t need.
5. Urine Formation
   -What’s left in the tubules becomes urine, made up of waste products and excess substances.
6. Cleaned blood
   -Now free of most wastes and excess substances leaves the kidney through the renal vein and continues circulating.

Question 11

Kidney conditions:
 Kidney Failure
 Chronic Kidney Disease
 Kidney Cancer
 Kidney Stones

Two Main Hormones
1. Vitamin D (active form)
2. Erythropoietin

Vitamin D
Most of the vitamin D that is in the blood is inactive and it is modified by the kidney and other tissues to activate it.

Active vitamin D helps:
 Regulate immune system response to infection
 Maintain healthy bones
 Absorb calcium from food

ERYTHROPOIETIN
Produced when oxygen levels in the blood are low. It acts in bone marrow to stimulate the production of mature red blood cells, to maintain healthy oxygen levels in our tissues.

Question 13

Additional Hormone-like Substances

•Prostaglandins
- Lipid-derived, hormone-like substances
- Help stimulate renin production

•Renin
- An enzyme made by kidneys
- Vital for the renin angiotensin aldosterone system (RAAS)
- Plays a major role in regulating blood pressure

Question 14

Kidney Response to Other Hormones
 Active Vitamin D
 Aldosterone
 Prostaglandins
 Cortisol
 Parathyroid
 Calcitocin

Question 15

What Could Go Wrong with the Kidneys?

FUNCTIONS AND PROBLEMS OF KIDNEYS:

ROLE OF KIDNEYS
 Filters waste
 Regulates fluids and minerals
 Control blood pressure

WHEN PROBLEMS OCCUR
 Toxin buildup
 Mineral imbalance
 Symptoms: Fatigue, swelling, high BP, back pain

CAUSES AND RISK FACTORS: MAIN CAUSES
 Diabetes
 High Blood Pressure
 Infections
 Glomerular diseases

AT RISK
 Has a family history
 Frequently takes pain reliever
 Does not drink enough water
 Practice an unhealthy lifestyle

Question 16

How to Protect Your Kidneys:
 Stay hydrated
 Eat healthy, less salty
 Monitor BP and blood sugar
 Avoid self-medication
 Have regular check-ups

Question 17

HOW FISH MAINTAIN AN INTERNAL BALANCE OF SALT AND WATER

Challenges Faced by Fish:

 Water and salt levels differ inside and outside the fish’s body.
 Skin is thin (lalo na sa gills), so water/salt can easily move in or out.
 Water tries to enter the fish (osmosis).
 Can cause imbalance if not controlled.

Question 18

How Fish Deal with it: Osmoregulation:

 Osmoregulation keeps internal salt-water levels balanced.

 Fish fight the natural movement of salt/water.

 Helps them survive in both freshwater and marine environments.

 Essential for survival and efficiency.

Question 19

Freshwater Fish

1. Freshwater fish have very efficient kidneys that excrete water quickly.
2. They also reabsorb salt from their urine before it is ejected to minimize losses.
3. Actively take salt from their environment using special cells in the gills.

Question 20

Marine Fish

In marine environments, fishes face the opposite problem there‘s relatively more salt and less water outside their bodies. Consequently, there is a tendency to take on salt and lose water.

To combat this, marine fishes drink vast amounts of water and urinate little. Salt is a more complicated problem: special cells in the gills actively eliminate salt at the cost of extra energy and these fishes do not absorb any salt from the water they drink.