1Lesson

Organs Description Function

1- Mouth

• A cavity contains : A ) Teeth

↓ 32 in the adult ↓ 16 in each jaw ↓ 4 incisors 2 canines 10 molars

B ) Tongue

C ) Salivary glands

3 pairs

Cut food Grind the food

- Turns & mixes up the

food with saliva - Tastes food

Secretes saliva which contains enzymes converts starch into sugar

What do you know about your digestive system ?

2- Pharynx

3- Esophagus 4 – Stomach

5- Small intestine 6- large intestine

Common cavity leads to esophagus & trachea Muscular tube Muscular sac Its length 7 m Starts with duodenum followed by ileum Starts from the end of small intestine ending in the anus ( located at the end of rectum )

Common path for food & air Allows food to pass from mouth to stomach Mixes the food with digestive juices ( as gastric juice ) that digests protein incompletely

-The food is completely digested by helping of bile , pancreatic juice & intestinal juice

Note: bile & pancreatic juice are poured in duodenum while intestinal juice is poured in ileum - Digested food is absorbed blood

Throw its wall

distributes it

all over the body

Note: Bile juice helps to digest fats where it changes

fats into a fatty emulsion

- absorbs water from food remains

- ejects the wastes outside the body throw the anus

Lesson 2 ?bout respiratory systemWhat do you know a

• Nose - Filters the air from dust and warms it

• Pharynx - Common cavity leads to esophagus and trachea

• Trachea -Is supported with incomplete cartilaginous rings -Branches into two bronchi - Is lined with cilia to eject up the strange objects

• larynx Voice box

• Epiglottis Closes trachea during swallowing

• Lungs

- Occupy the thoracic cavity - Are surrounded by the ribs - Gas exchange takes place throw alveoli

• Diaphragm - Separates the thoracic cavity from the abdominal cavity - Helps in the processes of inhalation and exhalation.

Comparison between inhalation and exhalation

Exhalation Inhalation P.O.C Relaxes & moves up Contracts &

moves down • Diaphragm muscle

Becomes narrow Enlarges • Thoracic cavity Carbon dioxide &

moves outside Oxygen enters

the lungs • Gas moved

Give reason: 1 – Nose is lined with hair & mucous layer: To filter dust from air before entering lungs 2- Nose contains blood capillaries : To warm air

3- Trachea is supported with incomplete rings: To be opened all the time 4 – Trachea is lined with cilia: To eject up the strange objects 5- The presence of epiglottis at the upper part of larynx To close the trachea during swallowing.

The alveoli have a thin wall: -6 To allow the gas exchange.

Unit One Lesson No. 3

The cell The cell : is the building unit of the living organism body.

Structure of the cell :

Cell parts Animal Plant

Nucleus

Cytoplasm

Plasma membrane

Cell wall

Chloroplasts

vacuole

√

√

√

x

x

√

√

√

√

√

√

√ • Nucleus : dark oval body

Function : It has a big role in cell division.

• Cytoplasm : fill the space of the cell. Function: Biological operations are acted by it.

• Plasma membrane : surrounds the cell.

Function : controls the substances entering into the cell or leaving it.. Unicellular organisms : They are not seen by the naked eye. Examples : Bacteria and Yeast. They can do all biological functions. Yeast fungus (unicellular organism)

Structure of Yeast fungus

Economic importance of the yeast fungus. It is used in a lot of industries such as :

1- Making bread. 2- Making alcohol

Lessons ( 4 ) &( 5) Importance of sunlight – energy paths

The photosynthesis process:- "It is the process by which the green plants make their food" Sun light Carbon + water starch + oxygen Chlorophyll

Starch Oxygen The living organisms are divided into:

producers consumers decomposers - Can make their food by themselves Ex: -green plants - Algae - Some kind of bacteria

- Depend on green plants to get their food Ex: - human - animals Herbivores: eat plants or grass only. Ex: Cow – chicken Carnivores: eat animals only. Ex: lion Omnivores: eat both animals &plants Ex: human.

- Get their food by decomposing the dead body or wastes Ex: - Fungi - some kind of bacteria

Changes the colour of iodine solution into dark blue

Increases the glowing of splint

"It is the path that the energy transmits in the form of food from a living organism to another" Ex1: Ex2:

"It is a group of overlapping food chains"

Food web

Green plant rabbit fox lion

Aquatic plant Aquatic insect Fish Whole

Food chain