Exam Four

Q uestion One: Give reasons for:

1- Roots of plants are important for the soil.

Because they add nutrients to the soil and they hold the soil in place.  

2 - Rockets and aeroplanes have streamline shape.

To decrease the air resistance.  

3 - We should avoid smoking and smokers.

To keep our circulatory system healthy.  

Q uestion Two: Write the scientific term:

1- The movement of blood from heart to all body parts.

Major blood circulation  

2 - The force arises between air particles and objects that move through.

Air resistance  

3 - The two tubes that transfer urine from kidney.

ureters  

4 - The organ that gets rid of sweat and excesses salts.

Skin  

5 - Blood vessels that carry blood from body parts to heart.

Veins  

Q uestion Three: Compare between:

1- Sand soil and silt soil. (size of particle – aeration – color)

Q uestion Four: What will happen if?

1- Surface area of car increases.

Air resistance will increase.  

2 - White blood cells do not exist.

Microbes will attack the body  

3 - The valve does not exist.

Blood will move in two directions between vertical and atrium.  

Q uestion One: Write one function for:

1- Ball bearings:

Decrease friction inside machines.  

2 - Aorta:

Transfers blood from heart to all body parts

3 - Urinary bladder:

Collects urine until it expelled out.  

4 - Plasma:

Transfers digested food in blood.  

Q uestion Two: Complete the following:

1- From soil pollutants are ……… and ……… .

pesticides – chemicals  

2 - Humus add nutrients to ……… .

soil  

3 - The clay soil has ……… compactness while silt soil has ……… aeration.

hard - medium  

4 - The friction force between glass and glass is ……… than glass and dry cement.

smaller  

5 - The friction force affects in ……… direction of movement.

opposite  

Q uestion Three: Write the scientific term:

1- The soil type which is rich with humus.

Silt soil  

2 - The cells which carry oxygen.

Red blood cells  

3 - The force that causes rise in temperature of machines.

Friction force  

4 - The soil that is suitable for cotton.

Clay soil

Q uestion Four: Choose the correct answer:

1- The most suitable soil for cultivation is ……… . (silt – clay – rocky – sand)

silt

2 - The largest artery in heart is ……… . (aorta – vena cava – pulmonary - vessel)

aorta

3 - The cells that help in forming blood clot. (white blood cells – red blood cells – plasma – platelets)

platelets

4 - The friction force inside machines can be decreased by ……… . (gears – water – ball bearing – wood)

ball bearing