4.10 - Excretory system

SCIENCE

what is excreation?

Excretion is the biological process by which waste products and toxic substances are eliminated/removed from the body.

Excretion of Skin

Removal of salt and water (sweat) through sweat glands.

Excretion of Lungs

Breathes in Oxygen (O2) and excretes Carbon Dioxide (CO2)

Excretion of liver

Breaks down toxins and wastes and transforms them into bile

Excretion of kidneys

Removes urea and excess water in the form of urine

what is Urea

A waste product formed from the breakdown of proteins, excreted in urine (pee) by the kidneys.

what is the 4 Main excretion organs

Kidneys, Lungs, Skin, Liver

where is the kidneys located in your body?

: Near hips.

shape & colour of kidneys

Reddish-brown, bean-shaped.

number of kidneys we have

2

how important is our kidneys?

Our kidneys are very important and vital for survival and we can only last a few days without them before dying

what do kidneys do

Kidneys filter blood

what are nephrons?

Nephrons are the functional units of the kidneys that filter blood and produce urine.

how much nephrons do we have in each kidney?

we have about 1 millions nephrons in each kidney (about 2 million in total)

what do nephrons do?

nephrons remove waste and excess chemicals.

what is ureters?

Ureters are muscular tubes that transport urine from the kidneys to the bladder.

what is the bladder

The bladder is a muscular sac that stores urine until it is excreted from the body.

how much liquid can the bladder hold?

The bladder can hold approximately 400 to 600 milliliters of urine.

what is the urethra

The urethra is a tube that carries urine from the bladder to the outside of the body during urination.

what is the nephrons structure and function

Nephrons are the functional units of the kidneys, consisting of a renal corpuscle and renal tubule. They filter blood, removing waste and excess substances to form urine.

what is blood concentration and what affects it?

Blood concentration refers to the amount of dissolved substances, such as electrolytes and nutrients, in the blood. It can be affected by factors like hydration levels, diet, and kidney function.

what do the kidneys use water for?

kidneys use water to remove waste and regulate blood volume and pressure.

how does water intake affect urine?

Water Intake: More= dilute urine Less= concentrated urine

what happens when you get kidney disease?

- Kidney disease affects waste removal from blood.

what is haemodialysis?

Haemodialysis is a medical procedure that uses a machine to filter waste products and excess fluid from the blood when the kidneys are unable to perform this function. It helps maintain the body's balance of electrolytes and fluid.

why are livers essential for survuival?

The liver performs vital functions such as detoxifying harmful substances, producing bile for digestion, and regulating metabolism, making it essential for overall health and survival.

What is bile?

Bile is a digestive fluid produced by the liver that aids in the digestion and absorption of fats in the small intestine.