ClickBiology

Cambridge IGCSE BiologyExtended Level

Cells

ClickBiology

ClickBiology

You should be able to:

• Identify and describe the structure of plant cells and animal cells, and describe the functions of their parts.

• Describe the difference between animal cells and plant cells.

• Explain the structure and function of specialised cells: red blood cell, muscle cells, ciliated cells, xylem vessels and root hair cells.

• Define the terms tissue, organ and organ systems, with examples.

ClickBiology

A section through a liver cell (animal cell):

cell membrane

cytoplasm

nucleus

DNA

controls what enters and leaves the cell

metabolic (chemical) reactions occur here

contains the DNA and so controls the cell

contains the coded instructions to make proteins

ClickBiology

Section through a palisade cell of a leaf (plant cell)

cell membrane

nucleus

cytoplasm

chloroplast

large sap vacuole

cellulose cell wall

Site of photosynthesis

Storage of nutrients and waste products.

Provides protections and support for cell

ClickBiology

You should be able to:

• Identify and describe the structure of plant cells and animal cells, and describe the functions of their parts.

• Describe the difference between animal cells and plant cells.

• Explain the structure and function of specialised cells: red blood cell, muscle cells, ciliated cells, xylem vessels and root hair cells.

• Define the terms tissue, organ and organ systems, with examples.

ClickBiology

Comparing animal and plant cells

Found in both animal and plant cells

Found only in plant cells

cell membrane cellulose cell wall

nucleus large sap vacuole

cytoplasm chloroplast

ClickBiology

You should be able to:

• Identify and describe the structure of plant cells and animal cells, and describe the functions of their parts.

• Describe the difference between animal cells and plant cells.

• Explain the structure and function of specialised cells: red blood cell, muscle cells, ciliated cells, xylem vessels and root hair cells.

• Define the terms tissue, organ and organ systems, with examples.

ClickBiology

Red blood cells transport oxygen

cell surface membrane cytoplasm contains no nucleus

cytoplasm contains haemoglobin

bi-concave disc shape

allows more room for haemoglobin

increases surface area over which absorption of oxygen can occur

haemoglobin is a protein which carries the oxygen molecules

ClickBiology

Muscle cells contract and enable movement of the body

nucleuscell surface membrane

protein strands

The strands of protein slide over each other making the muscle cell (fibre) shorter and causing the muscle to contract

Muscle cells have many nuclei

muscle

ClickBiology

Ciliated cells move bacteria and dust away from the lungs

cilia

magnification X3000

nucleus

Cilia are small extensions of the cell. They beat rhythmically to sweep mucus, which has trapped bacteria and dust, away from the lungs

ClickBiology

Xylem vessels transport water and minerals up the plant

xylem vessel

lignin

no cytoplasm

longitudinal sectioncross-section

water-proof and strong;helps support the plant

hollow: allows for continuous flow of water and dissolved mineral ions

xylem vessels are continuous tubes

ClickBiology

Root hair cells absorb minerals and water from the soil

cytoplasm

contains no chloroplasts as no photosynthesis is needed

root hair cell

increases surface area for absorption of water and mineral ions

Cross-section of a root hair cell

cell membrane semi-permeable, so will allow water and mineral ions into the cell

ClickBiology

You should be able to:

• Identify and describe the structure of plant cells and animal cells, and describe the functions of their parts.

• Describe the difference between animal cells and plant cells.

• Explain the structure and function of specialised cells: red blood cell, muscle cells, ciliated cells, xylem vessels and root hair cells.

• Define the terms tissue, organ and organ systems, with examples.

ClickBiology

A tissue is a group of cell of similar structure that form a shared function

Animal tissues:

muscle tissue

nervous tissue

upper epidermal tissue

palisade mesophyll tissue

spongy mesophyll tissue

lower epidermal tissue

Tissues found in the leaf

Cross-section of a leaf

ClickBiology

An organ is a structure made of a group of tissues working together to

perform specific functions

Plant organs include the stem and the leaves

heart

stomach

lungs liver

brain kidneys

ClickBiology

An organ system is a group of organs that coordinate to perform related functions

In plants the shoot is an organ system consisting of leaves and the stem

lymphaticsystem

respiratorysystem

digestivesystem

excretorysystem

reproductivesystem

muscularsystem

skeletalsystem

nervoussystem

endocrinesystem

circulatorysystem

ClickBiology

Levels of organisation

nerve cell nervous tissue

brain nervoussystem

Homo sapiens

smallest largest

cell tissue organ organsystems

organism

ClickBiology

Now you should be able to:

• Identify and describe the structure of plant cells and animal cells, and describe the functions of their parts.

• Describe the difference between animal cells and plant cells.

• Explain the structure and function of specialised cells: red blood cell, muscle cells, ciliated cells, xylem vessels and root hair cells.

• Define the terms tissue, organ and organ systems, with examples.

ClickBiology

Now write down everything you remember

• Don’t refer to your text book straight away, see what information you have retained.

• Check the notes you have made by re-watching the video or checking your book

ClickBiology

Cambridge IGCSE Biology

ClickBiology