Biology paper 1

• Diffusion is the net movement of particles from an area of high concentration to an area of lower concentration
• Osmosis is the diffusion of water molecules from a high concentration of water to a low concentration of water across a semi permeable membrane
• Active transport is the movement of substances against their concentration gradient. The substance moves from an area of low concentration to an area of high concentrations, across a partially permeable membrane
• Salmonella is a bacteria disease that can be killed with antibiotics
• Salmonella is spread by indigestion contaminated food
• Animals and plants are eukaryotic
• Eukaryotic cells contain their genetic material enclosed in a nucleus
• Eukaryotes also have a cytoplasm and a cell membrane
• In prokaryotic the genetic material is not enclosed in a nucleus
• The cell wall supports and strengthens the cell , its made from cellulose and found it plant cells , fungal cells and bacterial cells
• The cell membrane controls which substances can enter and leave the cell found in all cells
• The cytoplasm is where most chemical reactions take place found in all cell types
• The mitochondria is where Aerobic respiration takes place and where ATP is produced found in animal cells , plant cells and fungal cells
• The chloroplast is where photosynthesis Occurs and sugar is produced found in plant cells
• The vacuole stores cell sap and helps maintain cell shape found in plant cells
• Ribosomes is where protein synthesis happens found in all cells
• Plasmids are small rings of Dna found in bacteria cells
• The nucleus is where dna is stored and it controls the activities of the cell found in animal cells , plant cells and fungal cells
• Digestive system

  Mouth

  Stomach

  Small intestine

  Large intestine
• The small intestine produces amalayse protease and lipases
• The pancreas produces amalayse protease and lipases
• Bile is made in the liver but stored in the gallbladder
• The stomach produces pepsin a protease enzyme and breaks down proteins into amino acids
• Villi have a food blood supply , a single layer of cells on their surface and there is many of them
• The large intestine absorbs water
• Biological molecules are found in living organisms and are produced by cells
• Nutrients are substances that are needed for growth repair and metabolism
• Proteins are made up of long chains of amino acids bonded together
• Proteins are broken down in the small intestine and stomach
• Lipids are broken down in the small intestine
• Disease refers to a group of conditions that can cause ill health
• Leaves are a site of photosynthesis
• Water is transported to plant by roots and xylem
• Carbon dioxide enters leaves through the stomata
• Waxy cuticle is a layer of lipids in leaf
• Bile neutralises acids and emulsifies fats
• Carbohydrates are broken down by amalayse into maltose
• Proteins are broken down by protease into amino acids
• Lipids / fats are broken down by lipase into glycerol amd fatty acids
• Carbohydrates proteins and fats are all made in pancreas and small intestine