EXCRETORY SYSTEM

INDEX

5. Anatomy of Kidney

6. The Production of Urine

7. Function of Excretory System

8. Diseases of excretory System

1.Excretion

2. Excretory Organ

3. Excretory Products

4. Urinary System

WHAT IS EXCRETION?

Excretion is the process of removing cellular

waste.

It is not removal of undigested material (

Egestion – removal of undigested food

matter )

GOAL – Maintain homeostasis

There are four main excretory organs:

Lungs

Colon

Skin

Kidneys

mouth

Take Note !!

The liver is not an excretory organ, but

produces many products which are

excreted elsewhere.

LUNGS

COLON

SKIN

Renal Capsule

Protects kidney

Nephron

Medulla

Made up of pyramids

Pyramid

Made up of collecting ducts

Calyx

Collects urine from collecting

ducts

Papilla

Tips of each pyramid, fits into calyx

Renal artery

Carries blood to kidneys

Renal vein

Carries blood fromkidneys

Ureter

Carries urine from pelvis

to bladder for storage

KIDNEYS

EXCRETORY PRODUCTS

Carbon

Dioxide

Excess

Water

Excreted mainly via

Excreted mainly via

EXCRETORY PRODUCTS

Urea

Bile

Pigments

Excreted in the

faeces

URINARY SYSTEM

The Urinary

System is a group

of organs in the

body concerned with

filtering out excess

fluid and other

substances from the

bloodstream.

PARTS OF URINARY

SYSTEM

Kidney

Ureters

Bladder

Urethra

KIDNEY

Kidneysthey remove urea

and other waste

products from the

blood and form

urine.

Kidneys filter about 1700 liters of blood daily

in the average adult.

Average person loses 2l of liquid per day.

URETERS

Uretersthey carry

urine from the

kidney to the

bladder

BLADDER

Bladder it

stores urine

before it is

released from

the body. It

has a

muscular wall.

URETHRA

Urethra Itcarries urine outof the body.

• Menurethra iscommon to thereproductivesystem

• Womenurethra is anindependant tube

THE ANATOMY OF THE KIDNEYS

Blood enters the kidneys through the

renal arteries

Each kidney is made up of thousands

of small functional units known as

nephrons. Each one of these

nephrons filters and purify the blood

independently.

Glomerulus capsule

which contains lots of

blood capillaries

Bowman’s capsule surrounds the

glomerulus

The tubules and

the loop of Henle carry the urine to the

ureters

Renal cortexBowman’s capsules

Renal medulla

loops of Henle

and collecting ducts

Renal pelvis ducts which collect

the urine produced

by the nephrons.

THE PRODUCTION OF URINE

The formation of urine is a very

selective process.

Urine contains:

water

toxic substances (urea, uric acid,

etc.)

urea

uric acid

ammonia

TAKE NOTE !!

The composition of

sweat is similar to

urine.

It is produced by

filtering the blood

that reaches the

skin.

FILTERING

1. Filtering:Substances go

from the glomerulus to

the Bowman’s capsule

REABSORPTION

2.Reabsorption:

Water and

useful substances

go back from the

tubules to the blood

URINE

3. Urine(water, urea,

uric acid, salts)

arrives to the

renal pelvis,

where reaches

the ureters.

URINE

Urine is a liquid produced by the

kidneys, collected in the bladder and

excreted through the urethra.

FLOW OF URINE

Glomerulus

Renal Tubules

Renal Pelvis

Renal Calices

Ureters

Renal cortex

Renal capsule

Renal medulla

Ureter

Renal vein

Renal artery

Nephron

THE FUNCTIONS OF THE

EXCRETORY SYSTEM

The primary function of the excretory system is:

To get rid of wastes

Eliminates useless by-products excreted from

cells

Eradicates harmful chemical build-ups

Maintains a steady, balanced chemical

concentration

DISEASES OF EXCRETORY SYSTEM

Kidney

stones crystals of

uric acid

DISEASES OF EXCRETORY

SYSTEM

Cystitis inflammation of the bladder

caused by a bacterial infection.

DISEASES OF EXCRETORY

SYSTEM

Renal

insufficiency

kidneys do not

filter the blood

correctly and

waste products

are not removed

from the blood