7D Organisms

Question 1

Apart from support and movement, what are the functions of the skeleton?

Answer 1

Protection of vital organs, production of blood cells, storage of minerals

Question 2

What is the function of the bone marrow?

Answer 2

Produces blood cells

Question 3

How are bones attached to each other?

Answer 3

Ligaments

Question 4

What is the function of a tendon?

Answer 4

To attach muscle to bone

Question 5

Where is cartilage found?

Answer 5

At the joints of bones

Question 6

Explain why cartilage is important.

Answer 6

Reduces friction, prevents the ends of bones grinding against each other during movement and wearing away

Question 7

How are hinge joints and ball and socket joints different?

Answer 7

Hinge joints only move in one direction, ball and socket joints can move all around.

Question 8

Describe how muscles move bones.

Answer 8

A muscle contracts and pulls a tendon which pulls a bone.

Question 9

What happens to muscle cells when they contract?

Answer 9

Get shorter and fatter

Question 10

What happens to muscle cells when they relax?

Answer 10

Get longer and thinner

Question 11

Explain why muscles which moves bones need to work in pairs.

Answer 11

Muscles can only pull bones, two muscles are needed to pull bones in opposite ways

Question 12

What are antagonistic muscles?

Answer 12

Pairs of muscles which work in opposite ways

Question 13

Give an example of a pair of antagonistic muscles.

Answer 13

Biceps and triceps, quadriceps and hamstrings

Question 14

What happens to your forearm if your biceps contract and your triceps relax?

Answer 14

Forearm moves up

Question 15

How do your muscles allow you to hold objects in your hand?

Answer 15

Exert a force against gravity

Question 16

A bodybuilder is lifting a dumbbell which weighs 600N. How much force are their muscles exerting?

Answer 16

600N

Question 17

What are the three bones in the human leg?

Answer 17

Femur, tibia, fibula

Question 18

Name the two muscles in the thigh.

Answer 18

Quadriceps (front) and hamstrings (back)

Question 19

To bend your leg at the knee, which muscles must contract?

Answer 19

Hamstrings

Question 20

To straighten your leg, which muscles must contract?

Answer 20

Quadriceps

Question 21

What happens if too much tension is put on a tendon?

Answer 21

It can snap or pull

Question 22

Why do ligaments need to be elastic?

Answer 22

When the joint is bent, the ligament can stretch and then return to its normal shape without snapping

Question 23

What might happen if you pulled a ligament?

Answer 23

It would be painful to bend a joint

Question 24

Which bones are found in our toes?

Answer 24

Phalanges

Question 25

Why is it important for bones to contain collagen?

Answer 25

So they can bend a little without breaking

Question 26

How do doctors usually fix a fracture in the arm or lower leg?

Answer 26

Fibreglass cast

Question 27

What is a compound fracture?

Answer 27

Where the bone breaks the skin

Question 28

Why is the risk of infection higher for a compound fracture?

Answer 28

It is easier for microorganisms to get into the blood through the wound

Question 29

What is osteoporosis?

Answer 29

A condition where bone density decreases and bones become fragile

Question 30

Give two possible risk factors for osteoporosis.

Answer 30

Menopause, getting older, smoking, heavy drinking, family history, underweight

Question 31

Give two ways a doctor can help treat osteoporosis.

Answer 31

Medicines to help strengthen bones, calcium and vitamin D supplements

Question 32

Why can’t we completely prevent osteoporosis?

Answer 32

Cannot change family history, can only try to reduce the chance of developing it

Question 33

What are cells?

Answer 33

The basic building blocks of life

Question 34

What is formed from a group of tissues working together?

Answer 34

An organ

Question 35

Name the 5 levels of organisation from smallest to largest.

Answer 35

Cell, tissue, organ, organ system, organism

Question 36

What is a specialised cell?

Answer 36

A cell which is adapted to perform a certain function

Question 37

Name the organs present in the digestive system.

Answer 37

Stomach, small intestine, large intestine, pancreas

Question 38

What is the function of the circulatory system?

Answer 38

To pump blood around the body

Question 39

What type of tissue is the heart made from?

Answer 39

Muscle tissue

Question 40

How are nerve cells specialised for their function?

Answer 40

They are very long to connect different parts of the body

Question 41

What is an organelle?

Answer 41

A part of the cell, e.g. a nucleus

Question 42

Describe the function of the cell membrane.

Answer 42

Separates the inside and outside of the cell, allows substances in or out of the cell

Question 43

Where do most of the cell’s reactions take place?

Answer 43

Cytoplasm

Question 44

Which part of the cell controls its activities and contains the DNA?

Answer 44

Nucleus

Question 45

What is the function of the mitochondria?

Answer 45

Provide energy by respiration

Question 46

Name three organelles which are found in plant cells but not in animal cells.

Answer 46

Cell wall, vacuole, chloroplast

Question 47

Which organelle is responsible for providing the plant with food?

Answer 47

Chloroplast

Question 48

What is the difference between a eukaryotic and prokaryotic cell?

Answer 48

Eukaryotic cells contain a nucleus but prokaryotic cells do not

Question 49

What is a specialised cell?

Answer 49

A cell which is adapted to perform a certain function

Question 50

How are red blood cells adapted to fit through capillaries?

Answer 50

Small and flexible so they do not get stuck

Question 51

Why do nerve cells have a long, thin axon?

Answer 51

To carry electrical signals long distances around the body

Question 52

Why are muscle cells bundled together?

Answer 52

So they work together to pull on a bone

Question 53

Why do muscle cells and root hair cells need lots of mitochondria?

Answer 53

For energy

Question 54

How do root hair cells speed up the absorption of water and minerals?

Answer 54

Having a projection into the soil giving them a large surface area

Question 55

Which cell is responsible for photosynthesis in the plant?

Answer 55

Palisade cells

Question 56

How does a microscope allow us to see small objects like cells?

Answer 56

Using lenses to focus light and magnify small objects

Question 57

Why do we add iodine to the onion cells?

Answer 57

To make it easier to see them

Question 58

How do we keep the specimen in place on the microscope slide?

Answer 58

By placing a cover slip on top of the specimen

Question 59

Why must you be careful not to create air bubbles when preparing the specimen?

Answer 59

You could mistake them for parts of the cell

Question 60

Name the part of the microscope where we place the slide.

Answer 60

Stage

Question 61

Why do we lower the stage to its lowest point before looking through the eyepiece?

Answer 61

To reduce the chance of the slide and objective lens coming into contact with each other and potentially breaking

Question 62

Which objective lens should we use first?

Answer 62

The lowest power lens

Question 63

How do you find the total magnification you are using?

Answer 63

The objective lens multiplied by the eyepiece

Question 64

Why do unicellular organisms have to be very well adapted to their environment?

Answer 64

They do not have specialised cells to carry out different functions

Question 65

How are bacterial cells similar to plant and animal cells?

Answer 65

They have cytoplasm and a cell membrane

Question 66

What is the difference between a eukaryotic and prokaryotic organism?

Answer 66

A eukaryotic organism has cells with a nucleus, prokaryotic cells do not

Question 67

What group of organisms may be unicellular or multicellular?

Answer 67

Fungi

Question 68

Why are yeast cells classed as eukaryotic?

Answer 68

They have a nucleus

Question 69

Describe one way yeast are useful to us.

Answer 69

Brewing beer/wine – they produce alcohol Baking bread – they make bread rise

Question 70

In what way do protozoa act like animals?

Answer 70

They hunt for their food

Question 71

How are protozoa different to plant cells?

Answer 71

They do not have a cell wall or chloroplasts