1. Cell Structure and function

Question 1

Define Unicellular

Answer 1

A unicellular organism, also known as a single-celled organism, is an organism that consists of a single cell. E.g. a bacteria

Question 2

Define multicellular

Answer 2

A multicellular organism, is an organism that consists of multiple cells. e.g. a oak tree or a human

Question 3

What is a cell?

Answer 3

The most basic unit of life that all organisms are made of.

Question 4

Why are cells called the building blocks of life?

Answer 4

Living things are made up of them ‘ all joined together’

Question 5

Define ultrastructure

Answer 5

The ultrastructure of a cell is its fine structure as revealed at high magnification.

Question 6

Define Organelle

Answer 6

Animal, fungal and plant cells all contain structures called organelles. These are specialised for particular functions .

Question 7

Name 3 structures in an animal cell

Answer 7

Cell membrane, cytoplasm and nucleus

Question 8

What shape is an animal cell?

Answer 8

It has an irregular structure

Question 9

What is the function of the cytoplasm?

Answer 9

Site of chemical reactions.

Question 10

What is the function of the nucleus?

Answer 10

Controls cell activity, contains the genetic material - the DNA

Question 11

What is the only cell not to have a nucleus?

Answer 11

BACTERIA
(And as an exception the animal red blood cell)

Question 12

What is the function of the cell membrane?

Answer 12

Controls which substances enter and leave the cell

Question 13

What is the shape of a plant cell?

Answer 13

It has a regular rectangular shape

Question 14

What 3 additional structures does a plant cell have compared to an animal cell?

Answer 14

Vacuole, chloroplast and cell wall.

Question 15

What is the function of the vacuole?

Answer 15

Provides the plant with water and temperature regulation, contains cell sap

Question 16

What is cell sap

Answer 16

Sugary Water (Stores materials and provides mechanical support, it is vital for plant cell osmosis).

Question 17

What is the function of the cell well?

Answer 17

Provides the plant with structure and support

Question 18

What is the plant cell wall made of?

Answer 18

Cellulose

Question 19

What is the only cell not to have a cell wall?

Answer 19

Animal cell

Question 20

What is the function of the chloroplast?

Answer 20

Contains the pigment chlorophyll, where photosynthesis takes place

Question 21

What is the function of a ribosome? (L5)

Answer 21

Ribosome is the site of protein synthesis

Question 22

What is the function of a mitochondria?

Answer 22

Mitochondria is the site of aerobic respiration

Question 23

What is a bacteria? (L5)

Answer 23

Unicellular microorganisms which have cell walls but lack an organised nucleus, including some that can cause disease.

Question 24

Define flagellum (L5)

Answer 24

flagellum is a microscopic hair-like organelle used by cells and bacteria for movement. (can help them swim in liquid)

Question 25

Define plasmid (L5)

Answer 25

A plasmid is a small, extrachromosomal DNA molecule within a bacterial cell

Question 26

Is a fungal cell described more as an animal or plant cell (L5)?

Answer 26

This is a trick question. and the answer can be either depending on how you justify it. if you say plant cell, you say it is because it has a cell wall. if you say animal cell it is because it does not have a vacuole or chloroplasts.

Question 27

Name three parts of a microscope

Answer 27

Any three of the following.... Eyepiece, objective lens, stage, stage clips, mirror, fine focusing dial and course focusing dial.

Question 28

What part of the microscope reflects light into the eyepiece?

Answer 28

The mirror

Question 29

What is the job of the objective lens on a microscope?

Answer 29

The help you see the sample by magnifying it. Microscopes commonly include 4x, 10x, 40x, and 100x objective lenses.

Question 30

Why do we use a stain when preparing a slide.

Answer 30

It allows us to more clearly see the organelles inside a cell.

Question 31

What stain is useful when viewing plant cells such as in onion tissue?

Answer 31

Iodine solution

Question 32

What stain is useful when viewing animal cells such as in cheek cells?

Answer 32

Methylene Blue

Question 33

Define a specialised cell

Answer 33

Cells that perform specific functions are called specialised cells. Each of these cells has special features which allow them to work differently and carry out their intended functions.

Question 34

Each type of cell has its own job to do. A sperm cell has special features that allow them to perform their functions effectively. List some.

Answer 34

ON order that they can swim to fertilise the female egg they have.... - A tail moves them towards an egg cell. - Many mitochondria release energy for movement. - Part of the tip of the head of the sperm, releases enzymes to digest the egg membrane to allow fertilisation to take place. - The nucleus contains the genetic material for fertilisation. - Sperm are produced in large numbers to increase the chance of fertilisation.

Question 35

Nerve cells transmit electrical signals in the nervous system. Describe why they are well suited to their function

Answer 35

- 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. - Nerve cells have branched connections at each end. These join to other nerve cells, allowing them to pass messages around the body. - They have a fatty (myelin) sheath that surrounds them. The fatty sheath increases the speed at which the message can travel.

Question 36

Roots hold plants in place as they grow and also absorb water and minerals from the soil. Describe how root hair cells are specialised to maximise the job they do.

Answer 36

Roots divide into smaller and smaller branches as they travel into the soil. The outside surface of roots are covered with root hair cells, which have tiny 'hairs' which poke into the soil. This massively increases the surface area for the root hair cell to absorb more water and minerals.

Question 37

A red blood cell is a specialised animal cell. what special features does it have to help it do it's job of carrying oxygen around the body.

Answer 37

They contain haemoglobin, which carries oxygen molecules. They don't have a nucleus, allowing more space to carry oxygen. They are a flat disc shape with dips on both sides (biconcave). This gives them a large surface area, and the best chance of absorbing as much oxygen as they can in the lungs.