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Cells and Organisation

The microscope

Diffusion

Osmosis

Active transport

Animal cells

Plant cells

Organisation

Cell division

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The Microscope

Mirror

Stage

Objective lens

Eyepiece

Focus

3

Diffusion

Container filled at the bottom with bromine gas

Your teacher may have shown you a container filled with bromine gas, at the bottom, in a fume cupboard.

What would you observe after several minutes?

What do we call this effect?

The bromine gas spreads out to fill the whole container.

The effect is known as diffusion.

The bromine gas spreads out because the bromine molecules move from regions of high concentration to regions of low concentration.

4

Osmosis

Water molecule Semi-permeable membrane

Solute molecule

High concentration of water molecules

Low concentration of water molecules

Water molecules diffuse through the semi-permeable membrane to even out the concentrations

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Active Transport

Water molecule Cell membrane

Mineral ion

High concentration of mineral ions

Low concentration of mineral ions

Minerals ions move against the concentration gradient as they move from the region of low concentration to the

region of high concentration, this process requires energy

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Plant Nucleus

Nucleus

Root tip packing cells x200

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Animal Cells

Cell membrane

Cytoplasm

Nucleus

Mitochondria

It should be noted that some animal cells do have a small food vacuole

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Animal Cell Parts

Cell membrane Cytoplasm

Nucleus Mitochondria

Where chemical reactions occur controlled by enzymes, a jelly-like

substance that is granular in nature

Controls the cell, contains the genetic information, in the form of chromosomes,

for cell replication

Organelles that are found in the cytoplasm of animal cells (and plant cells) that produce energy from food

Controls what enters and leaves the cell, it also gives the cell shape and support

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Plant Cells

Cell membrane

Nucleus

Cell wall

Cytoplasm

Vacuole

Chloroplast

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Plant Cell Parts

Cell membrane Cytoplasm

Nucleus Cell wall

Where chemical reactions occur, a jelly-like

substance that is granular in nature

Controls the cell, contains the genetic information, in the form of chromosomes,

for cell replication

Made of cellulose, helps to support the plant

Controls what enters and leaves the cell, it also gives the cell shape and support

Vacuole

Contains cell sap, consisting of water and

mineral salts

Chloroplast

Organelle that absorbs light energy to convert

carbon dioxide and water into glucose

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Cells

Cells are the building blocks of life

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Tissue

Cells of the same type working together are known as tissue

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Several different types of tissue working together to do a specific job are called an organ

Organ

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Organ System

Several different organs working together to do a specific job are called an organ system

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Organism

An organism has several organ systems all working together to fulfil the seven life processes

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Cell Division

The type of cell division whereby cells divide and the two daughter cells have both a full set of chromosomes is known as mitosis.

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Cell DivisionHow do we grow?

It is through a process known as cell division.

Some cells, known as stem cells, have the ability to ‘become’ any specialised cell in an organism.

When a stem cell becomes a specialised cell it loses its ability to undergo cell division.

The process of cell division begins with the nucleus dividing into two.

Each of these two daughter nuclei has an identical copy of the genetic information held within the parent nucleus.

The cell membrane then divides in between the two daughter nuclei to form the two daughter cells.

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Cell Division

Stem cell

Stem cell

Stem cell

Cell that will specialise

Specialised cell

Cell that will specialise

Stem cell

Stem cell

Specialised cell

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Where Does Mitosis Occur?

Mitosis occurs throughout plants and

animals…

Red blood cells are replicated in the bone marrow of bones such

as the femur

Root hair cells are replicated at the

tips of roots

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Exercise 1: Label the Instrument

Light

4. ______

3. ____________

1. _________

2. _______

Stage

Objective lens

Eyepiece

Focus

What is the name of this optical instrument? __________Microscope

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Exercise 2: Link the Boxes

Cell membrane

Nucleus

Cytoplasm

Controls what enters and leaves the cell, it also gives the cell shape and support

Controls the cell, contains the genetic information, in the form of chromosomes,

for cell replication

Where chemical reactions occur controlled by enzymes, a jelly-like substance that is

granular in nature

Mitochondria

Organelles that are found in the cytoplasm of animal

cells (and plant cells) that produce energy from food

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Exercise 3: Link the Boxes

Cellulose

Vacuole

CytoplasmContains cell sap,

consisting of water and mineral salts

Organelle that absorbs light energy to convert

carbon dioxide and water into glucose

Made of cellulose, helps to support

the plant

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Exercise 4: Link the Boxes

Diffusion

Osmosis

Active transport

When water molecules move across a semi-permeable

membrane from regions of high concentration to regions

of low concentration

When mineral ions move against the concentration

gradient to enter and leave cells

When gases and liquids spread out from regions of

high concentration to regions of low concentration

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Exercise 5: Short Questions

1. By what process does carbon dioxide gas enter a leaf through the stoma?

2. By what process does water enter a root hair cell from soil?

3. By what process do mineral salts enter root hair cells from soil?

4. By what process is glucose absorbed in the small intestine?

5. By what process does oxygen gas leave a leaf through the stoma?

Diffusion

Osmosis

Active transport

Active transport

Diffusion

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Exercise 6: Label the Diagram

2. _____________

6. _________

3. ________

5. ___________

1. ________

4. ___________

Cell membrane

Cell wall

Vacuole

Nucleus

Cytoplasm

Chloroplast

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Exercise 7: Label the Diagram

2. _____________

4. _________

1. __________

3. _____________

Mitochondria

Cytoplasm

Nucleus

Cell membrane

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Exercise 8: Animal Cells

1. What is the function of the organelle mitochondria?

2. Where is the genetic information found in a cell?

3. What do we call the jelly-like substance found in cells where most of the chemical reactions?

4. What is the function of the cell membrane?

5. What do we call the process of cell division where each of the daughter nuclei have a full set of genetic information?

To release energy from food by respiration

The nucleus

The cytoplasm

To control what substances enter and leave the cell

Mitosis

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Exercise 9: Plant Cells

1. What is the cell wall made from?

2. Which organelles contain the green substance chlorophyll?

3. Where is cell-sap found?

4. What is the function of the cell wall?

5. Give two examples of plant cells that do not contain chloroplasts.

Cellulose

Chloroplasts

In the vacuole

To provide support for the plant

Epidermis cells (not guard cells) and root hair cells