Biology Human Health And Systems

Question 1

Ingestion/Eating

Answer 1

1. Ingestion/Eating food is taken into the body
2. Digestion food is broken down
3. Absorption digested food passes into the blood stream
4. Assimilation using the food in the cells of the body
5. Elimination getting rid of undigested food

Question 2

Physical digestion

Answer 2

Large pieces of food breaking them down to smaller pieces happens in teeth (mouth) stomach (churning)

Question 3

Chemical digestion

Answer 3

Uses enzymes
Enzymes speed up reactions without being used up in the reaction
Act as a substrate and breaks down the product

Question 4

Chemical digestion

Answer 4

◼ Amylase in mouth
◼ Enzymes in the
stomach
◼ Most chemical
digestion happens in
small intestine
◼ Bile made in liver to
break down fats
◼ Pancreas makes
digestive juices
which contain
enzymes

Question 5

Functions of parts

Answer 5

◼ Mouth: physical and
chemical digestion
◼ Oesophagus:
brings food from
mouth to stomach
◼ Liver: makes bile
◼ Stomach: Physical
and chemical
digestion

digestive juices
◼ Small intestine:
Most chemical
digestion
◼ Large intestine:
Water reabsorption ◼ Pancreas: makes
digestive juices
◼ Small intestine:
Most chemical
digestion
◼ Large intestine:
Water reabsorption
◼ Rectum: Stores
undigested food
◼ Anus: undigested
food passes out
◼ Rectum: Stores
undigested food
◼ Anus: undigested
food passes out

Question 6

Mouth

Answer 6

•The job of the
teeth break is
physical
digestion.
•The job of the
amylase in
saliva is
chemical
digestion.

Question 7

The oesophagus

Answer 7

The
oesophagus
carries food
to the
stomach.

Question 8

Stomach

Answer 8

The food
passes into
the
stomach.
•The
stomach
mixes and
churns the
food. This is
more
physical
digestion

Question 9

Small intestine

Answer 9

•Most of the
chemical
digestion
occurs in the
small
intestine.
•Nutrients
from the food
are absorbed
into the blood.

Question 10

Components of blood

Answer 10

Red bllod cells
White blood cells
Platelets
Plasma

Question 11

plasma

Answer 11

• Liquid part of the blood
• Pale yellow – mostly water
• Function : to transport chemicals and heat
– Chemicals (Useful): Food, Hormones
– Chemicals (Waste): CO2, Salts, Urea
– Heat: Generated from chemical reactions,
transported around to maintain 37°C
• Also carries the red blood cells, white blood
cells, and platelets.
Red Bl

Question 12

Red blood cells

Answer 12

• Round, flattened discs, curve inward
near centre
• Small, no nucleus, formed in bone
marrow
• Very numerous – approx 5million per drop
blood
• Function : transport oxygen to cells
• Red colour comes from haemoglobin
they contain.
• Haemoglobin picks up oxygen in the
lungs
• It later releases it in other parts - e.g.
muscle

Question 13

White blood cells

Answer 13

• Larger than Red Blood Cells
but fewer in number
• No definite shape – shape
can change
• They are also made in the
bone marrow
• Function : to fight infection
• Some can surround micro-organisms and destroy them
• Others produce proteins called antibodies
• Antibodies help to destroy micro-organisms such as
bacteria

Question 14

Platelets

Answer 14

• Smaller than red or white blood
cells
• They are formed in the bone
marrow
• They are formed from larger
cells breaking down into pieces
• Function: help to form blood
clots
• When a blood vessel is injured, platelets help to form a clot
• Clotting prevents loss of blood, and prevents micro-
organisms getting in
• Clots are temporary barriers while repair and healing is
taking place

Question 15

Systems of Tubes and Plump

Answer 15

• Blood being a fluid, needs tubes in
which to flow
• These tubes are called blood
vessels
• They come in three main types:
– Arteries
– Veins
– Capillaries
• Good blood flow requires the aid of a good pump
• In the human circulatory system this pump is the heart
• In an average lifetime, the heart beats more than 2.5 billion
times, without ever pausing to rest

Question 16

Arteries

Answer 16

• Carry blood AWAY from the heart
• Flow of blood is strong and at high pressure
• Artery walls are thick and strong to withstand this
pressure
• Blood is under pressure – forced to move in one direction
• There is no need for valves in arteries to prevent
backwards flow
• All arteries (except pulmonary artery) carry oxygenated blood

Question 17

Veins

Answer 17

• Carry blood BACK to the heart
• Flow of blood is weaker and pressure is low
• Vein walls are thinner and weaker than artery walls
• Pressure is low, so there is a danger of backward flow of
blood, especially when flow direction is against gravity
• Valves in veins at regular intervals, allow blood to flow
forwards, but prevent reverse flow
• All veins (except pulmonary vein) carry deoxygenated blood

Question 18

Capillaries

Answer 18

• These are tiny blood vessels
• There are a huge number of them in the body
• Capillaries are found between arteries and veins
• Capillaries have very thin walls which allow materials to
pass in and out with the surrounding cells and tissue.

Question 19

The heart

Answer 19

• Is an organ about the size of a
clenched fist
• Function: pumps blood around
the body
• It pumps blood by contracting
periodically
• Cardiac muscle provides the
contraction
• Unlike regular muscle, cardiac muscle doesn’t tire easily
• Resting heart rate in adults is about 72 bpm(beats per minute)
• In exercise, the heart beats faster, so that the blood can
carry chemicals faster around the body e.g. Oxygen

Question 20

Pulse rates

Answer 20

• When the heart contracts, it
squeezes blood into the arteries
under pressure.
• As blood flows down the arteries,
surges of pressure can be felt where
the arteries are close to the surface
• Areas where it can be felt are:
– At the wrist
– Inner arm near elbow joint
– At the sides of the neck
• A surge of blood felt at these locations is called a pulse
• The pulse rate is at the same pace as the heart rate

Question 21

Two blood circuits

Answer 21

• The human circulatory system has
what is known as Double Circulation
• Blood passes through the heart twice
on its journey around the body
• It consists of two circuits:
• 1: Pulmonary Circulation
– Blood leaves the heart
– goes to the lungs to become oxygenated
– returns to the heart
• 2: Systemic Circulation
– Blood leaves the heart
– travels to other parts of the body
– returns to the heart

Question 22

Structure of the heart

Answer 22

• The heart is split down the
middle into two sides by the
septum
• Each side has an upper
chamber called an atrium
(plural atria)
• Each side also has a lower
chamber called a ventricle.
• This makes a total of 4
chambers
• Valves between the upper
and lower chambers ensure
that blood only flows in one
direction

Question 23

Left versus right

Answer 23

• Heart diagrams are
always shown as if facing
the person
• The left side of the heart
appears on the right of
the diagram, and vice
versa
• The left side of the heart always pumps oxygenated
blood (shown in red), received from the lungs, and pumps it
to the body.
• The right side always pumps deoxygenated blood (shown
in blue), received from the body, and pumps it to the lungs

Question 24

Blood vessels of the heart

Answer 24

• Heart diagrams are
always shown as if facing
the person
• The left side of the heart
appears on the right of
the diagram, and vice
versa
• The left side of the heart always pumps oxygenated
blood (shown in red), received from the lungs, and pumps it
to the body.
• The right side always pumps deoxygenated blood (shown
in blue), received from the body, and pumps it to the lungs

Question 25

Whats respiration

Answer 25

Respiration is the release of
energy from food.
• The equation for respiration in words is:
• Glucose + Oxygen Carbon dioxide + Water + Energy

Question 26

What are the two types of respiration

Answer 26

• Aerobic Respiration • needs oxygen to
release energy from food.
Anaerobic Respiration does not use
oxygen to release energy from food.

• Anaerobic Respiration does not use
oxygen to release energy from food.

Question 27

How does Oxygen get to our
Cells??

Answer 27

• Oxygen is carried by the haemoglobin in
red blood cells to all other cells of the bod