The Human Excretory System

Question 1

Describe the structure of the human renal excretory system.

Answer 1

1. The urinary system is made up of the kidneys, ureters, bladder and urethra.
2. The blood supply to and from the kidneys is by the renal arteries and renal veins.
3. The kidney has different parts. The outer part is the cortex and the inner part is the medulla.

Question 2

What is the function of the kidney?

Answer 2

1. Lies in the abdominal cavity below the diaphragm on each side of the vertebral column
2. The right kidney is usually lower than the left
3. Responsible for the creation of urine and the filtration of blood

Question 3

What is the function of the ureter?

Answer 3

1. It is the tube that carries urine from the kidney to the urinary bladder
2. Humans have two, each connected to one kidney.
3. Uses peristalsis, the rhythmic contraction of the ureter smooth muscle, to help move the urine into the bladder

Question 4

What is the function of the urinary bladder?

Answer 4

1. It is a muscular sack in the pelvis, just above and behind the pubic bone. When empty, the bladder is just about the size and shape of a pair.
2. The bladder collects and stores urine until when it is ready to be discharged through the urethra.

Question 5

What is the function of the urethra?

Answer 5

1. In both genders, the rector works as a tube connecting the urinary bladder to the genitals.
2. While the function means the same for both genders, slide differences exist due to difference between male and female genders.

Question 6

What is urination?

Answer 6

Urination refers to the process of disposing urine from the unary bladder through the urethra to the outside of the body. This process is voluntary and is also known as micturition.

Question 7

How is urine produced?

Answer 7

1. Blood is filtered in the kidneys at high pressure, allowing it to pass through the glomerulus of the nephrons.
2. Small molecules like glucose, urea, water, and ions pass into the nephron, while large molecules like proteins stay in the blood.
3. The filtered fluid moves through the nephron, containing glucose, urea, water, and ions. Certain molecules are reabsorbed back into the blood.
4. Reabsorption is selective and works through diffusion, osmosis, and active transport.
5. Leftover fluid becomes urine, with water, ions, and urea being the main components.
6. Urine is stored in the bladder, moving from the kidneys to the bladder through the ureters.
7. The volume and concentration of urine are affected by water intake, temperature, salt intake, and exercise.