• What are cells?
– Cells are the smallest basic unit of living things.
• What do they do?
– Cells take in raw materials and making new substances.
• Why do they do this?
– In cells, organelles carry out activities to keep the organism alive.
– E.g. synthesising proteins and fats, releasing energy from glucose.
What are the central ideas of
Movement of Substances?
• What processes describe how substances move from one region to another?
– osmosis, or
– diffusion, or
– active transport.
• What is the above dependent on?
– Type of substance
– Concentration gradient or water potential gradient.
What is the link between Cells &
Movement of Substances?
• Cells take in raw materials to make new substances such as proteins and fats.
• Cells also take in glucose and water for cell activities.
• How do the raw materials enter the cell? How does water and glucose enter the cell?
What will we learn in Nutrients?
Proteins, fats, glucose & water are examples of nutrients.
• What are the raw materials needed to synthesise these nutrients?
• What are the chemical elements that make up these nutrients?
• What is the importance of nutrients in humans?
• What kind of foods contains these nutrients?
• What test can we conduct to find out the presence of nutrients in food?
What are NUTRIENTS?
• Definition: Chemical substances in food that may provide…
– Energy
– Structural materials
– Regulate growth
– Tissue repair
• Also known as biological molecules.
• Some nutrients are organic compounds (contains the element carbon) while others are inorganic compounds. Nutrients can be found in variety of food and drinks that we consume Other Nutrients – Vitamins, Minerals, Fibre
No energy value.
Needed in small quantities to maintain a healthy body.
fibre (found in fruits) – stimulate peristalsis to prevent constipation
Vit C (in fruits) – healthy skin & gums