Life Processes, Cells and Cell Organisation

Question 1

How to use a microscope to view slides. (6)

Answer 1

1. Move the stage (the flat ledge the slide sits on) down to its lowest position. (1)
2. Place the glass slide onto the stage. (1)
3. Select the lowest power objective lens. (1)
4. Turn the coarse focus knob slowly until you are able to see the cells. (1)
5. Turn the fine focus knob slowly until the cells are in focus and you can see them clearly. (1)
6. Repeat steps 1-5 using the higher power magnification to see the cells in more detail. (1)

Question 2

List and describe the 7 Life Processes.(7)

Answer 2

Movement (1)
Respiration (1)
Sensitivity (1)

Growth (1)
Reproduction (1)
Excretion (1)
Nutrition (1)

Question 3

Draw and label a plant and animal cell. Compare and contrast both cells (7)

Answer 3

The four key components of most animal cells are:

Nucleus - this contains the DNA of the organism and controls the cell’s activities. (1)
Cytoplasm - the liquid that makes up most of the cell in which chemical reactions happen. This is mainly water. (1)
Cell membrane - a flexible outer layer that surrounds the cell and controls which substances can pass into and out from it. (1)
Mitochondria - tiny parts of cells floating in the cytoplasm where energy is released from glucose from food. The mitochondria, found in the cell cytoplasm, are where most respiration happens. (1)

Plants cells, on top of what animal cells include, they have:

Cell wall: a tough outer layer of the cell, which contains cellulose to provide strength and support to the plant. (1)
Vacuole: a space inside the cytoplasm that contains a watery liquid called cell sap. It keeps the cell firm. (1)
Chloroplasts: structures found in the cells of green parts of plants only (leaves and stems) which contain a green pigment called chlorophyll in which photosynthesis occurs. (1)

Question 4

List at least five specialised cells and explain how they are
adapted to their function. (10)

Answer 4

Red blood cells. (1)
They don’t have a nucleus, allowing more space to carry oxygen. (1)

Sperm cells. (1)
A tail helps the sperm moves towards an egg cell.

Egg cells. (1)
The egg cell’s cytoplasm contains nutrients for the growth of the early embryo. (1)

Nerve cells. (1)
They are thin, and can be more than one metre long in your spinal cord. This means they can carry messages up and down the body over large distances very quickly. (1)

Muscle cells. (1)
Cardiac (heart) muscle cells contract and relax to pump blood around our bodies for our entire lives. They never get tired. (1)
Smooth muscle cells make up thin sheets of muscle, such as the stomach lining. They can also be arranged in bundles, or rings, like that in the anus. (1)
Skeletal muscle is joined to bones. Its cells contract to make bones move and joints bend. (1)

Question 5

Describe how organisms are organised and give
examples. (2)

Answer 5

Cell -Tissue - Organ - Organ System - Organism. (1)

Palisade Cell -
More Palisade = Tissue -
Other tissue = Organ = Leaf -
More Leaves + Other Organs = Shoot system -
Different Organ Systens make up a full Plant = Organism (1)

Question 6

Four main plant organs and how they are adapted to
their function. (1)

Answer 6

Flower (1)
Flowers have bright colours, smells and nectar which encourage pollinators to pay them a visit. (1)

Stem (1)
The stem carries water and nutrients to different parts of the plant. It also provides support and keeps the plant standing upright. (1)

Leaves (1)
A leaf usually has a large surface area, so that it can absorb a lot of light.

Roots (1)
Roots have a massive surface area for the root hair cell to absorb more water and minerals. (1)

Question 7

Nutrition, name the main food groups, giving examples and what they are needed for in the body.

Answer 7

Fruit and vegetables, for example, apples, bananas and broccoli, give us vitamins to keep our bodies working and help our immune system and fibre to help our digestion.

Carbohydrates, like pasta, bread and rice, keep our energy levels up.

Proteins, such as meat, beans, and eggs, build healthy muscles and allow our bodies to grow and repair.

Dairy, like milk, cheese and yoghurt, gives us calcium for strong teeth and bones. Many dairy-free alternatives have calcium added to them too.

Fats and oils, for example olive oil and butter, act as an energy store.

Question 8

What is meant by a balanced diet?

Answer 8

A balanced diet refers to the intake of a variety of foods in appropriate proportions, providing the necessary nutrients to support overall health and well-being. The goal of a balanced diet is to ensure that the body receives the right amount of carbohydrates, proteins, fats, vitamins, minerals, and water.

Question 9

Describe the food tests. How is iodine used to test for starch?

Answer 9