7A Cells - Board Works

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The 7 signs of life


Here is a picture of a plant cell and an animal cell. Cells are the smallest units of life.

Some cells can exist on their own, whilst others are found in groups.

Humans are a collection of many billions of cells, all working together.

Animal and plant cells


While some cells do look different, all cells have three basic features.

nucleus

cytoplasm

cell membrane

7A What is a cell?


The Cell - a living factory!


Role Check


Most cells have three basic parts.

nucleus cytoplasm cell membrane

But cells can be different shapes and sizes and also have different functions. This is because they are…

specialised

The shape of a cell is related to its function.

Where do you see this idea in sport? CLUE: World Cup!

7A Do all cells look the same?


Rugby players are different shapes and sizes because they do different jobs for the team.

Like rugby players, cells are different shapes and sizes because they perform different jobs.

Why are the players in a rugby union team different shapes and sizes?

7A Specialised rugby players


Whose cell is it anyway?


Plant cellsTherefore, if plants and animals are different shapes, they must be made of different shaped cells. Let’s have a look at the shape of a basic plant cell.

Apart from the shape, the cell

looks very similar to an animal cell.

However, here is how the plant cell differs from the

animal cell. Cytoplasm

Cell Membrane

NucleusStarch Grains

Cell Wall

Vacuole (contains cell

sap)

Chloroplast (contains

chlorophyll)


Animal, plant or both?


Now that we know what the basic structure of a plant and animal cell is, we can begin looking at the bigger picture.

Cells are not flat…..

…they are usually three-dimensional

The 3D shape of the cell will be determined by its location in the body and the job it does.

Cell shapes


You can make your own 3D cell using the following equipment.

• Plastic bag

• Cellulose paste

• Cardboard box

You will need to find some small objects to

suspend in the cellulose paste. These will

represent the internal structures of the cell.

Try to make a model of both the plant and animal cell. Then label these and display them.

Bring it to life!


A great way to visualize how a cell functions, is to become one!

Make sure you have a cell membrane and a nucleus as a minimum. Then you can choose from the list and role-play cell activity.

• Cell Membrane• Nucleus• Cell Wall• Vacuole• Water

• Glucose• Starch• Chloroplast• Light• Waste Material

You can get people to stand in a circle, holding hands to represent a cell membrane.

Then, get other people to be the nucleus and so on. If you are feeling adventurous, you can even dress up to represent the job of that part of the cell.

Cell-play


As we know, all life is built of cells. The way we look is the result of the types of cell we are made of and the way those cells are organised.

For example, if we look at the cells of the plant and animal, it is no surprise that plants and animals look different…

Animal

From Cell to Organism

Plant


Animal and Plant Cells


How is the body organised?

To help us understand this, think of how a school is organised.

A school needs to be very organised. Every pupil in the school needs to know where they should be and what they are doing. However...

Not all pupils study the same subjects.

Not all pupils can work together efficiently.

There is not room for all the pupils to be in the same place.


Therefore, a school uses the following system.

One pupil

Registration groups

Subject classes

A year group

A school



This hierarchy of organisation is also found in living organisms.

Each specific cell

Is grouped with cells similar in structure and function.

We call this a tissue.



Examples of Tissues

Animal Tissues Plant Tissues

Muscle

Bone

Liver

Skin

Lung

Mesophyll

Phloem

Xylem

Can you think of any more types of tissue?



Together, they are known as an….

ORGAN

Different tissues link together to carry out a certain job.

TISSUECELL


Next, different organs are linked together by tubes/ vessels…..

Organ 1

Organ 2

Organ 3

Organ 4

To become..An organ system



The body is then made up of different organ systems working together to carry out all the functions of a living organism.

In summary...

Cell Pupil

Tissue Registration groups

Organ Subject Classes

Organ system Year

Organism School



Why are living organisms organised like this?

Well, it allows complex organisms to carry out many different jobs at the same time.

For example -

Grow

Reproduce

ExcreteRespire

Respond to things

It also means our bodies don’t waste energy!

They are more efficient.



Activity 11 – Organs


Where do cells come from?

Think of the following situations…..

REPAIR...

You cut your finger. The wound is eventually healed and weeks later you can’t even see where the cut used to be.

REPRODUCTION...

Your body can make sex cells. In humans, these cells are the sperm and egg. These cells contain the same genetic information that can be found in other body cells.

GROWTH...

Your body loses cells and cells are constantly dying. However, your skin never disappears and you don’t get smaller.

This is because you are constantly producing newnew cells and these new cells are produced from your existingexisting cells.


REPAIR

REPRODUCTION

GROWTH

You will have seen that our bodies produce cells for three main reasons:

New cells are produced from old cells dividing.



Q. Can you think of a problem if one cell splits to produce two cells?

A. The two new cells would be smaller than the original cell.

Therefore, a cell needs to make new copies of the material Therefore, a cell needs to make new copies of the material inside itself as well as the membrane and nucleus.inside itself as well as the membrane and nucleus.

Just before a cell divides, it will appear to grow slightly as it reproduces everything inside itself.

The nucleus must also divide into two equal halves.

This only occurs once the nucleus has doubled from its original size.



Cell division occurs extremely quickly and can happen over and over again.

Grow quicklyThis is how it is possible for the body to ...Repair cuts and replace dead cells quickly.Produce an enormous number of

reproductive cells.



Cell Division


Activity – animal cell


Activity – plant cell


Summary Drag the words into the correct places in the sentences.


Multiple choice questions


Look at the diagram below.

1. What is V?

A Nucleus

B Glycogen granules

C Starch grains

D Chloroplast

X

YZ

V


2. What is X?

A Nucleus

B Cytoplasm

C Cell Membrane

D Cell wall


X

YZ

V


3. What is Y?

A Nucleus

BCytoplasm

C Cell wall

DChloroplast


X

YZ

V


4. What is Z?

A Cell membrane

B Vacuole

C Cytoplasm

D Nucleus


X

YZ

V


A It is a jelly-like substance in which most of the chemical reactions take place.

B It controls the movement of substances into and out of the cell.

C It is the site of photosynthesis.

D It controls the activities of the cell .

5. Which of the following descriptions represents the function of the membrane?





D It controls the activities of the cell.

6. Which of the following descriptions represents the function of the nucleus?





D It controls the activities of the cell.

7. Which of the following descriptions represents the function of the cytoplasm?


8. What is M?

A Cell membrane

B Cytoplasm

C Cell coat

D Cell wall

M

Q

O

P

N

R



9. What is N?

A Cytoplasm

B Vacuole

C Cell membrane

D Starch grain

Look at the diagram below.M

Q

O

P

N

R


10. What is O?

A Nucleus

B Starch grain

C Glycogen granule

D Chloroplast


Q

O

P

N

R


11. What is P?

A Nucleus

B Starch grain

C Glycogen granule

D Chloroplast


Q

O

P

N

R


12. What is Q?

A Cytoplasm

B Vacuole

C Nucleus

D Chloroplast


Q

O

P

N

R


13. What is R?

A Cell wall

B Vacuole lining

C Cell membrane

D Cell coat


Q

O

P

N

R


A storage site

B site of photosynthesis

C site of reproduction

D site of excretion

14. Which of the following descriptions represents the function of the chloroplast?


A glandular tissue

B liver tissue

C muscle tissue

D brain tissue

15. Which of the following types of tissue is capable of contracting and causing movement?


A glandular tissue

B liver tissue

C muscle tissue

D brain tissue

16. Which of the following types of tissue is capable of making useful substances (e.g. enzymes)?


A cell

B organ

C organ system

D tissue

17. Which of the following describes a group of cells of the same type all doing the same job?


A cell

B organ

C organ system

D tissue

18. Which of the following describes a group of tissues working together to do the same job?


A cell

B organ

C organ system

D tissue

19. Which of the following describes a group of organs of the same type all doing the same job?

7A Cells - Board Works

Documents

animal cell

cell functions

cell shapesnow

plant cell shape

basic plant cell

roleplay cell activity

cellplaya great way

different shaped cells