The Human Organism

Question 1

What does A+ (A positive) blood indicate?

Answer 1

This red blood cell is in blood group A and has the Rhesus chemical on it.

Question 2

Why is the Rhesus factor important?

Answer 2

For safe blood transfusions

Question 3

What are the main blood groups?

Answer 3

A, B, AB, O

Question 4

Describe red blood cells

Answer 4

• No nuclei (when mature)
• No mitochondria
• Biconcave shape (to give a larger surface area)

Question 5

What are mature red blood cells called?

Answer 5

Blood corpuscles

Question 6

What colour is haemoglobin?

Answer 6

Purple

Question 7

What colour is oxyhaemoglobin?

Answer 7

Bright red

Question 8

Describe lymphocytes

Answer 8

• Made in bone marrow
• Mature in lymphatic tissue
• Stored in spleen, lymph nodes, tonsils, adenoids and thymus gland
• Large round nucleus with very little cytoplasm

Question 9

Structure of a monocyte

Answer 9

•Kidney-shaped nucleus

Question 10

What is the need for a circulatory system?

Answer 10

To supply cells with all the materials they require

Question 11

Benefits of a closed circulatory system

Answer 11

• Moves blood around the body faster

* Allows alterations in blood flow to different body organs

Question 12

Why are animals with a closed circulatory system considered to be more active?

Answer 12

Blood is pumped around the body faster, allowing nutrients and oxygen to de distributed faster to the cells

Question 13

Location of the heart

Answer 13

Located between the two lungs, slightly to the left-hand side of the thorax, just above the diaphragm

Question 14

Structure of the heart

Answer 14

• Made of cardiac muscle

* Surrounded by double membrane called pericardium

Question 15

Benefits of a double-circulation system

Answer 15

• Allows oxygenated and deoxygenated blood to be kept separate
• Ensures that the blood pressure is high enough to reach all parts of the body

Question 16

Why does the aorta have thicker walls?

Answer 16

Blood entering the aorta is under high pressure due to the contraction of the left ventricle

Question 17

What glands are associated with the digestive system?

Answer 17

• Salivary gland
• Liver
• Gall bladder
• Pancreas

Question 18

What glands are associated with the digestive system?

Answer 18

• Salivary gland
• Liver
• Gall bladder
• Pancreas

Question 19

What glands are associated with the digestive system?

Answer 19

• Salivary gland
• Liver
• Gall bladder
• Pancreas

Question 20

Where is bile made and stored?

Answer 20

Made in the liver, stored in the gall bladder

Question 21

What does the duodenum do?

Answer 21

Produces a range of digestive enzymes

Question 22

What enters the duodenum?

Answer 22

The products of the pancreas and liver

Question 23

What does sodium bicarbonate do in the pancreas?

Answer 23

Neutralises acid (chyme)

Question 24

By what process is food absorbed?

Answer 24

Diffusion

Question 25

Adaptations of villi for absorption

Answer 25

* Large numbers (increase surface area) * Thin walls * They have a rich blood supply to carry away water-soluble products

Question 26

Adaptations of small intestine for absorption

Answer 26

* Has numerous villi and microvilli * Walls of villi are thin * It is very long

Question 27

What are the four food groups?

Answer 27

* Cereals, bread and potatoes * Fruit and vegetables * Milk, cheese and yoghurt * Meat, fish and poultry

Question 28

To what vein do the venules in the villi lead to?

Answer 28

Hepatic portal vein

Question 29

Location of the respiratory system

Answer 29

Thoracic cavity/Thorax

Question 30

Why is breathing through the nose beneficial?

Answer 30

The nose filters, moistens and warms the air

Question 31

Adaptations of alveoli

Answer 31

* Huge number of alveoli - huge surface area * Thin wall * Moist surface * Enclosed in network of capillaries

Question 32

What is the name of the process that occurs in gas exchange?

Answer 32

Diffusion

Question 33

How is oxygen transported?

Answer 33

Oxygen combines with haemoglobin, to form oxyhaemoglobin.

Question 34

Describe inhalation

Answer 34

1. Diaphragm contracts 2. Intercostal muscles contract 3. Ribs move up and out 4. Volume of thoracic cavity increases 5. Pressure decreases 6. Air rushes in

Question 35

Describe exhalation

Answer 35

1. Diaphragm relaxes 2. Intercostal muscles relax 3. Ribs move down and in 4. Volume of thoracic cavity decreases 5. Pressure increases 6. Air is pulled out

Question 36

How does exercise affect breathing?

Answer 36

Exercise increases the rate of respiration.

Question 37

Describe Asthma

Answer 37

Symptoms: Breathlessness, Wheezy breathing Cause: Allergens like pollen and dust Prevention: Avoid allergens Treatment: Inhalers

Question 38

How does the brain control human breathing?

Answer 38

It monitors the levels of carbon dioxide in the blood that passes through it. The medulla oblongata controls this.

Question 39

What is the controlling factor in gas exchange in animals and plants?

Answer 39

Carbon Dioxide

Question 40

Describe the role of the skin in controlling body temperature in cold conditions

Answer 40

1. Piloerection, which then traps a layer of warm air. 2. Vasoconstriction, which reduces heat loss through skin. 3. Shivering, which produces heat to raise temperature.

Question 41

Main organs of excretion

Answer 41

Lungs, skin, kidneys

Question 42

Location of kidneys

Answer 42

In the small of the back

Question 43

Main processes in the kidneys

Answer 43

1. Filtration (Cortex) 2. Reabsorption (Cortex and Medulla) 3. Secretion (Cortex)

Question 44

How do the kidneys control blood pH?

Answer 44

They control the concentration of hydrogen ions in the blood

Question 45

What does urine consist of?

Answer 45

Water, Urea and Salts

Question 46

Functions of the kidneys

Answer 46

1. Excretion 2. Osmoregulation 3. pH control of body fluids