B4 - Organising Animals And Plants

Question 1

Red blood cell

Answer 1

Carry oxygen around the body

Question 2

White blood cell

Answer 2

Defend the body against infection from microorganisms

Question 3

Platelets

Answer 3

They help to clot blood at a wound

Produced in the bone marrow

Question 4

Plasma

Answer 4

It carries many substances dissolved in it including glucose for body cells

Question 5

Arteries

Answer 5

Carry blood away from your heart to your organs

Thick walls

Small lumen

Thick layer of muscles and elastic fibre

Question 6

Veins

Answer 6

Carry blood to your heart from your organs

Thin walls

Large lumen

Contains valves

Question 7

Capillaries

Answer 7

Links arteries and veins together

Walls are a single cell thick

Tiny vessel with a narrow lumen

Question 8

Advantages of artificial heart

Answer 8

The artificial heart is not rejected by the body

Keeps the patient alive whilst waiting for a transplant

Question 9

Disadvantages of artificial heart

Answer 9

Surgery can lead to bleeding and infection

Blood does not flow as easily and can led to clots so blood thinners need to be taken

Parts of the heart can wear out or stop working

Question 10

Advantages of artificial valves

Answer 10

The success rate is high

Last for 20 years

Question 11

Disadvantages of artificial valves

Answer 11

There could be serious complications with surgery

Question 12

Advantages of stents

Answer 12

The success rate is high

Lower the risk of a heart attack

Last for a long time

Question 13

Disadvantages of stents

Answer 13

Complications like bleeding, irregular heartbeat and infection

Arteries sometimes reclose

Question 14

Advantages of artificial blood

Answer 14

It is not rejected

Efficient at carrying O2

Question 15

Disadvantages of artificial blood

Answer 15

Effects are short lasting

Expensive

Question 16

Artificial pacemaker

Answer 16

A small battery operated device which sends electrical impulses to produce normal contractions

Used when you have an abnormal heartbeat

Question 17

Human gas exchange system

Answer 17

The lungs are adapted to absorb O2 and transfer CO2 to red blood cells

Question 18

Lungs

Answer 18

The trachea branch into two bronchi (one for each lung)

The bronchi splits into bronchioles, containing alveoli

The alveoli have a large surface area for gas exchange and once cell thick walls for greater rate of diffusion

Question 19

Diaphragm

Answer 19

When we inhale our diaphragm contracts, moving downwards

When we exhale our diaphragm relaxes and moves upwards

Question 20

Xylem

Answer 20

Transports water and minerals

Made out of dead cells and strengthened by lignin

Moves upwards

Question 21

Phloem

Answer 21

Transports sugars and amino acids

Contains sieve cells (specialised) and requires energy

Moves in two directions

Question 22

Transpiration

Answer 22

The evaporation of water from the leaves of a plant

Question 23

Factors affecting transpiration

Answer 23

Increase in temperature = more H2O lost from evaporation

Decrease in humidity = reduces concentration of H2O outside the leaf so diffusion from the leaf increases

Air movement increases = removes water vapour from leaf surfaces so more water diffuses

Light intensity increases = rate of photosynthesis increases so stomata open more often