The Human Body and Its Systems

In this presentation you will: explore the systems of the human body

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In this presentation, you will see how the cells of the human body are organized to enable it to function.

You will explore some of the systems the human body uses in order to work effectively and efficiently.

Levels of Organization

The human body is made up of many cells. It is multicellular. Within multicellular organisms, different levels of organization can be seen:

• Cells – the most basic unit of living things.

• Tissues – made up of groups of cells that carry out the same function.

• Organs – groups of tissues that work together to do a specific job.

• Organ systems – groups of organs that work together to do a specific job.

• Organism – a living structure made upof organ systems that can live, growand reproduce.

Lowest level of organization

Highest levelof organization Next >

1

What is the lowest level of organization found in the human body?

Question

A) An organism

B) Organ systems

C) Organs

D) Cells

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Organ Systems

The human body is very complex. In order to function properly, it uses various systems.

These systems are groups of organs that work together to carry out an important function within the body.

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The human circulatory system consists of the heart, arteries, veins and capillaries. The heart beats to pump blood through the arteries and veins around the body.

The Circulatory System

The circulation of blood around the body supplies our cells with the nutrients they need and removes the waste products that they produce.

Heart

Arteries

Veins

Capillaries

Arteries carry blood away from the heart while veins carry blood to the heart. Arteries and veins are connected by capillaries.

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The Respiratory System

During inspiration (breathing in) air enters the nose or mouth, and goes down the trachea.

Rib

Diaphragm

The respiratory system includes the nose, mouth, trachea, lungs and the diaphragm. Ventilation (breathing in and out) provides the body with the oxygen it needs and removes waste carbon dioxide.

Trachea

Alveoli

Lung

The trachea leads to two smaller tubes called bronchi. One bronchi (a bronchus) leads into each lung. These divide into smaller and smaller tubes called bronchioles.

The diaphragm flattens and the space that the lungs are in increases. The lungs also increase and fill with air.

Bronchus

Bronchiole

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The Respiratory System

Oxygen passes through the walls of the alveoli and into the blood in these capillaries. Carbon dioxide passes through the walls of the capillaries, into the alveoli.

Alveoli are surrounded by capillaries.

This movement of oxygen and carbon dioxide is called gas exchange.

The carbon dioxide is removed from the body during expiration (breathing out).

The bronchioles end in tiny sac-like structures called alveoli.

Alveoli Capillaries

2

In the human respiratory system, where does the process of gas exchange take place?

Question

A) Mouth

B) Trachea

C) Alveoli

D) Nose

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The Digestive System

The GI tract begins in the mouth and ends at the anus.

In the mouth, food is broken into smaller pieces by chewing.

Humans have to digest (break down) food in order to release the energy and nutrients stored in it.

Mouth

Anus

Stomach

Once swallowed, food travels down the esophagus, into the stomach.

Esophagus

Digestion occurs in the gastrointestinal (GI) tract or alimentary canal.

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The Digestive System

Material that is not needed by the body, or that cannot be digested, passes to the large intestine. Much of the fluid from the digestive juices is reabsorbed into the blood.

Remaining solid waste is stored in the rectum until it leaves the body via the anus.

Food then passes into the small intestine. Here, chemicals break the food down into small molecules that can enter the bloodstream.

Small intestine

Large intestine

Stomach

Rectum

In the stomach, acids break the food down further.

3

What is the correct path taken by food in the human digestive system?

Question

A) Small intestine, mouth, large intestine, stomach

B) Mouth, stomach, large intestine, small intestine

C) Mouth, stomach, small intestine, large intestine

D) Small intestine, stomach, large intestine, mouth

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The urinary system is made up of the kidneys, ureters, bladder and urethra. Its function is to remove liquid waste from the body.

The Urinary System

The kidneys filter waste materials from the blood. These waste materials combine with excess water to produce urine.

Urine travels to the bladder down two tubes called ureters. The urine collects in the bladder and once the bladder is full, the muscle at the base of the bladder, the sphincter, relaxes and it leaves the body via the urethra.

Kidney

Ureter

Bladder

SphincterUrethra

The nervous system controls the body’s actions. It consists of the brain, spinal cord and nerves.

The Nervous System

There are two main parts to the nervous system:

• The Peripheral Nervous System (PNS) consists of nerves that branch off from the spinal cord and brain, out to the rest of the body. Information is carried between the CNS, muscles and glands. Glands are groups of cells that produce substances that the body uses. For example glands produce the saliva in our mouths.

• The Central Nervous System (CNS) consists of the brain and spinal cord. Information from the body is carried to the brain via the spinal cord.

Brain

Spinalcord

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Some muscles move joints. They are attached to the skeleton by tendons and always work in pairs.

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The muscular system is made up of groups of stretchy tissue.

The Muscular System

One muscle contracts and moves the joint. Then the muscle relaxes and the second muscle contracts and moves the joint in a different direction.

The bicep contracts, pulls the front of the arm, and the arm lifts

The tricep contracts, pulls the back of the arm, and the arm lowers

This is because a muscle can only either contract (get tighter and shorter) or be in a relaxed state.

These are called voluntary muscles because they can be consciously controlled.

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We are able to move muscles such as those in our arms, legs, fingers and toes as and when we choose.

The Muscular System

Other muscles, such as the heart muscle, eye and muscles of the intestines cannot be consciously controlled. They are involuntary muscles.

Both the voluntary and involuntary movement of muscles are controlled by signals to and from the nervous system.

4

"The Muscular system and the Nervous system are both needed to make it possible to move a joint." Is this statement true or false?

Answer True or False.

Question

The Reproductive System

The purpose of the reproductive system is to produce offspring. For reproduction to occur, a male gamete (sperm) and a female gamete (egg) must meet and fuse together.

Sperm is made inside males’ testes. It cannot survive the warmth of the body so is kept in a sac outside the body called the scrotum.

Vas deferens

Epididymis

Testis

Penis

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Sperm mixes with other fluids to become semen, which can leave the body via the penis. Scrotum

Sperm

The Reproductive System

The female human has two ovaries that produce eggs (ova). Once a month an egg is released into a fallopian tube (oviduct).

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Ovary

Cervix

Vagina

Uterus

Fallopian tube

If sexual intercourse occurs, the egg and the sperm may meet in a fallopian tube and the egg can become fertilized. The fertilized egg travels to the uterus where it can develop into a baby.

The fallopian tube leads to a hollow pear-shaped organ called the uterus.

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The immune system is how the human body protects itself against harmful invading foreign bodies such as some bacteria and viruses.

The Immune System

If the body detects an invader, it releases large proteins called antibodies.

Lymph nodes

Tonsils

Lymphaticglands Spleen

AppendixBonemarrow

Thymus

Antibodies are made by white blood cells which are made in the organs of the immune system shown here.

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Each antibody is specific to a certain foreign body, so every time a new type is encountered, we have to make a new type of antibody.

The Immune System

Sometimes the body is not able to make the antibody in time and people get sick.

Antibodies bind with the bacteria or virus to block their effects. By joining together they form a clump which is easier for the body to destroy.

Bacteria attacks

White blood cells produce

antibodies

Antibodies

Antibodies bond with bacteria, to create large lumps

Summary

After completing this presentation you should be able to:

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show knowledge and understanding of the levels of organization within the human body

show knowledge and understanding of different human body systems

show knowledge and understanding of the structure and function of different human body systems

explore the major organs of the human body

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In this presentation you will learn about the main organs that are part of the human body.

You will explore the location of the organs and their functions.

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The Human Body

In order to function properly the human body has a number of different organs.

Each organ has a specific function that is important to the human body as a whole.

Cerebrum

Brainstem Cerebellum

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The Brain

The brain controls many body activities and has three main parts:

The cerebrum controls intelligent activities such as remembering, usinglanguage and thinking.

The brainstem controls activities such as breathing, circulation and digestion.

The cerebellum controls body posture and coordination.

1

Which part of the brain controls coordination?

Question

A) Cerebrum

B) Cerebellum

C) Brain stem

D) All of these

Aorta

Leftatrium

Leftventricle

Rightventricle

Rightatrium

Tricuspid valve

Pulmonaryvalve

Aorticvalve

Bicuspidvalve

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The Heart

The heart pumps blood around the body. This is because it is the blood's job to supply the cells of the body with the oxygen they need, and to remove the waste products they produce.

The left side of the heart pumps oxygenated blood from the lungs to the body.

The right side of the heart pumps deoxygenated blood from the body to the lungs.

3

This picture shows a simple outline of a human body. Where is the heart located?

Question

A) Label A

B) Label B

C) Label C

D) Label D

A

B

C

D

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The LungsThe lungs are responsible for supplying your blood with the oxygen that you breathe in. They also remove the carbon dioxide from your blood; this is what you breathe out.

Right mainstem bronchus

Trachea

Bronchi

Bronchioles

Pleural membrane

Rightlobes

Alveoli (on endof bronchioles)

4

Which of the following do lungs remove from the blood?

Question

A) Carbon dioxide

B) Food

C) Oxygen

D) Water

5

This picture shows a simple outline of a human body. Where are the lungs located?

Question

A) Label A

B) Label B

C) Label C

D) Label DA

B

C

D

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The Stomach

The stomach is used in food digestion. The stomach produces chemicals that break down the food into small molecules.

Esophagus

DuodenumMucousmembrane

Musclelayers

Stomach

Pyloricsphincter

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The Pancreas

The pancreas is important in food digestion. The pancreas produces chemicals that break up protein molecules within food.

Pancreas

Duodenum

Pancreaticduct

Hepatic vein

Gall bladder

Common bile duct

Portal vein

Hepatic artery

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The Liver

The liver is important in food digestion. The liver produces chemicals that break up fat molecules within food.

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The Small Intestine

The small intestine is used in food digestion. It is in the small intestine where the chemicals that are produced from the pancreas and the liver set to work breaking down the food.

The small intestine is long and the nutrients from the small, broken-down food molecules pass through the walls and into the blood. Once in the blood they are transported around the body to where they are needed.

Small intestine

Large intestine

Rectum

Anus

Appendix

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The Large Intestine

The large intestine is used in food digestion. The large intestine absorbs a lot of the water that gets mixed in with the food during the digestion process.

Small intestine

Large intestine

Rectum

Anus

Appendix

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The Kidneys

The kidneys clean our blood. Our cells produce waste products, some of which are poisonous to our bodies.

The kidneys filter our blood and remove the waste products. The waste gets turned into urine. Urine is stored in the bladder where it can be released when needed.

Bladder

Kidney

Adrenal gland

AortaVenacava

Urethra

Ureter

6

This picture shows a simple outline of a human body. Where are the kidneys located?

Question

A) Label A

B) Label B

C) Label C

D) Label D

A

BC

D

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The Sense Organs

Our sense organs alert us to changes within our environment.

We have five sense organs:

• Eyes: for seeing

• Ears: for hearing

• Nose: for smelling

• Tongue: for tasting

• Skin: for touching

Our sense organs contain nerves that send messages to our brains about what is happening in the world around us.

2

Which of the following organ types does the eye belong to?

Question

A) Digestive organs

B) Circulation organs

C) Sense organs

D) Respiration organs

Summary

After completing this presentation you should be able to:

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show knowledge and understanding of the location of the main organs in the human body

show knowledge and understanding of the function of the main organs in the human body