Cambridge IGCSE Biology Extended Level ClickBiology Cambridge IGCSE Biology Extended Level Cells

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.

A section through a liver cell (animal cell): cell membrane nucleus controls what enters and leaves the cell contains the DNA and so controls the cell cytoplasm DNA metabolic (chemical) reactions occur here contains the coded instructions to make proteins

Section through a palisade cell of a leaf (plant cell) chloroplast cell membrane large sap vacuole nucleus cellulose cell wall cytoplasm

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.

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

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.

Red blood cells transport oxygen cytoplasm contains no nucleus cell surface membrane allows more room for haemoglobin cytoplasm contains haemoglobin haemoglobin is a protein which carries the oxygen molecules bi-concave disc shape increases surface area over which absorption of oxygen can occur

Muscle cells contract and enable movement of the body Muscle cells have many nuclei nucleus cell surface membrane protein strands The strands of protein slide over each other making the muscle cell (fibre) shorter and causing the muscle to contract

Ciliated cells move bacteria and dust away from the lungs Cilia are small extensions of the cell. They beat rhythmically to sweep mucus, which has trapped bacteria and dust, away from the lungs nucleus magnification X3000

Xylem vessels transport water and minerals up the plant xylem vessels are continuous tubes xylem vessel no cytoplasm hollow: allows for continuous flow of water and dissolved mineral ions lignin water-proof and strong; helps support the plant longitudinal section cross-section

Root hair cells absorb minerals and water from the soil Cross-section of a root hair cell cell membrane semi-permeable, so will allow water and mineral ions into the cell cytoplasm contains no chloroplasts as no photosynthesis is needed root hair increases surface area for absorption of water and mineral ions

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.

A tissue is a group of cells of similar structure that perform a shared function upper epidermal tissue palisade mesophyll spongy mesophyll tissue lower epidermal Tissues found in the leaf Cross-section of a leaf Animal tissues: muscle tissue nervous tissue

An organ is a structure made of a group of tissues working together to perform specific functions heart lungs liver stomach brain kidneys Plant organs include the stem and the leaves

An organ system is a group of organs that coordinate to perform related functions lymphatic system digestive system reproductive system skeletal system endocrine system respiratory system excretory system muscular system nervous system circulatory system In plants the shoot is an organ system consisting of leaves and the stem

Levels of organisation systems cell tissue organ organism nerve cell nervous tissue brain nervous system Homo sapiens smallest largest

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. Now you should be able to Explain why many animals have a heart and circulation (a mass transport system) And Explain the importance of water as a solvent in transport, including its dipole nature.

Now write down everything you remember from the presentation Don’t refer to your text book straight away, see what information you have retained. Check the notes you have made by checking your book.

Edexcel AS Level Biology ClickBiology Next video: Transport into and out of the cell (diffusion, osmosis and active transport)