B2 - Organisation (Plant cell organisation (Epidermal tissue- covers whole…
B2 - Organisation
Plant cell organisation
Epidermal tissue- covers whole plant (waxy cuticles reduce water loss and transparent so light can pass through). Palisade mesophyll tissue- photosynthesis (contains many chloroplasts). Spongy mesophyll tissue- create air spaces which allow gas to diffuse in and out. Xylem and phloem- transport water, mineral ions and food. Tissue is adapted for gaseous exchange.
Phloem- transports food (dissolved sugar) made in leaves to go to the rst of the plant or for storage, travel in both directions this is called translocation.
Xylem- transports water and mineral ions from roots to the stem and leaves, this is called transpiration.
Transpiration rate is affected by : Light intensity, Temperature, air flow and humidity.
Guard cells adapted to open and close stomata for gaseous exchange and water loss.
Health and disease
Health is the state of physical, mental and social wellbeing.
Communicable disease is person to person or animal to person showing its contagious (normally through bacteria or virus).
Non-communicable disease cannot be spread and occurs over a long period of time gradually getting worse.
Some diseases can interact with one another such as cancer can be triggered by an infection by a certain virus.
Factors that may affect your health include : Diet, stress and life situations.
Stents - keep arteries open, due to coronary heart disease which means the artery is blocked by a layer of fat and has narrowed the artery restricting the amount of oxygen going around the body. This can be used long term however can be complications such as infection and blood clot.
Statins- reduce the amount of cholesterol, which is lipids (fat).This reduces the chance of coronary heart disease however have to take regularly forever and can give kidney failure and liver damage.
Artificial heart- mechanical device (normally temporary), this means its less likely to be rejected as made from metal and plastic however doesn't work as well as natural and could wear out or fail.
Faulty heart valve- Biological or mechanical, meaning it being damaged it could allow blood to flow in both directions creating bad circulation.
Artificial blood- blood substitution to keep patients alive in an emergency.
Catalyst, increases reaction without changing or being used up.
Active sit is specific to the substrate it needs to break down, this is by the 'lock and key' method. The active site has to be at the right temperature and ph scale otherwise will denature and will not fit the specific substrate
To calculate the rate of reaction it is Rate = 1000/Time
A group of similar cells form tissue, a group of different tissues form an organ and a group of organs form an organ system.
Different types of tissue such as : Muscular tissue (contract to move), Glandular tissue (makes and secretes chemicals) and epithelial tissue.
Enzymes and digestion
Amylase turn carbohydrates (starch) into simple sugar, found in the salivary glands, pancreas, small intestine. Protease turns protein into amino acids, found in the stomach, pancreas and small intestine. Lipase turns lipids (fat) into glycerol and fatty acids, found in the pancreas and small intestine. Bile is also neutralises stomach acid and breaks down fat into droplets.
1- Salivary gland (amylase) 2- oesophagus 3-Stomach (protease and hydrochloric acid) 4- Liver (bile produced) 5-Gall bladder (bile stored) 6- Pancreas (protease, amylase and lipase) 7- Small intestine (protease, amylase and lipase) 8- Large intestine (water absorbed) 9- Rectum
Cancer is an uncontrolled cell growth and division. There are two types of tumours, Benign which is the growth until there is no room but not cancerous. The other is Malignant which grows and spreads into the blood stream creating secondary tumours, this is very dangerous and cancerous.
Risk factors include; Smoking, obesity, uv exposure, viral infection and inheriting a faulty gene which cannot be changed.
Red blood cells carry oxygen around the body (has no nucleus, haemoglobin and oxyhaemoglobin). White blood cells (fight against infection using antibodies and antitoxins). Platelets (create blood clots). Plasma (the liquid that carries everything in the blood)
Arteries carry blood away from the heart (high pressure). The Capillaries exchange materials within the body (one cell thick). The veins take the blood to the heart (low pressure but contain valves to ensure blood travels the correct direction).
1- Oesophagus 2- Trachea 3- Bronchus 4- Bronchioles 5-Alveoli 6- Diaphragm (intercostal muscles, ribs, heart, Pleural membrane).
Risk factors of non-communicable disease
These include; lifestyle (exercise) or the environment. Some cause direct harm such as ; smoking, obesity, alcohol and radiation exposure
Benedict solution for sugars. Iodine solution for starch. Biuret solution for protein and Sudan III stain solution for lipids.
Right atrium, right ventricle, left atrium, left ventricle, Aorta, Pulmonary vein, body, vena cava, pulmonary artery and the lungs.