2701753
Description
Flashcards by dayna.tohidi8787, updated more than 1 year ago
|
Created by dayna.tohidi8787
over 9 years ago
|
|
| Question | Answer |
| Lipids | Oil Butter Eggs Dairy food |
| Proteins | Meat Fish Cheese Body building, growth and repair |
| Carbohydrates | Source of energy Bread Pasta Rice |
| Vitamin A | Good eyesight and healthy hair Fish liver oils Liver Butter Margarine Carrots |
| Vitamin c | Growth and repair of tissues Citrus fruits and vegetables |
| Vitamin D | Helps bones absorb calcium and phosphorus Fish liver oils, butter, made by skin in sunlight |
| Calcium | Make bones and teeth Dairy products Fish Bread Vegetables |
| Iron | Make haemoglobin in red blood cells Red meat Liver Eggs Green leafy vegetables |
| Rickets | Lack of vitamin D |
| Scurvy | Lack of vitamin C |
| Water | Solvent for the body Enzymes work in solution Carrying substances around the body |
| Fibre | Absorbs lots of water So food can move through the gut more easily |
| How food moves through the gut | Waves of muscle contractions known as peristalsis |
| Bile | Made in the liver Stored in the gall bladder Emulsifies fats Neutralises stomach acids |
| Egestion and excretion | Removal of undigested food out of the anus as faeces. Removing waste products of metabolism like urea and carbon dioxide. |
| Absorption and assimilation | Absorption is when digested food molecules are absorbed into the bloodstream in the small intestine Assimilation is when the digested food products are absorbed into the cells of the body by diffusion and assimilated (used for energy and to build up into chemicals needed by the cells) |
| Blood | Plasma White blood cells Red blood cells Platelets |
| nitrates | amino acids and proteins cell growth stunted and yellow older leaves |
| phosphates | Making DNA, cell membranes respiration and growth Poor root growth and yellow older leaves |
| potassium | help enzymes for photosynthesis and respiration poor root and flower growth discoloured leaves |
| Magnesium | making chlorophyll for photosynthesis yellow leaves. |
| need for transport systems | in order to deliver and take away substances to and from individual cells quickly |
| transport system in plants | xylem and phloem- vascular bundle |
| xylem | carry water and mineral ions from roots up the shoot to the leaves in the transpiration stream. |
| phloem | transport sugars, like sucrose and amino acids from where they are made to other parts of a plant. |
| translocation | movement of food substances around the plant |
| Root hair cells | draw in water by osmosis - higher concentration usually in soil, and they take in minerals by active transport |
| waxy cuticle | prevents water loss by evaporation, NOT transpiration! |
| why do plants have a transpiration stream | because plants constantly need to draw up water from the roots through the xylem vessels in order to replace the water lost by evaporation |
| why is there transpiration | because there needs to be stomata for gas exchange for photosynthesis, but because there is more water inside the leaf than outside of the leaf, water escaped the leaves through the stomata by diffusion |
| factors which affect the rate of transpiration | Wind speed Humidity Temperature Light intensity |
| Humidity | High humidity- air is moist- not steep concentration gradient- low transpiration rate Low humidity- transpiration rate is fast, as it is drier, so water moves from high to low concentration |
| Estimating transpiration rate | Use a potometer |
| investigating how humidity affects transpiration | seal potometer with a plastic bag that has been sprayed with al little bit of water wind speed- use a fan to increase wind speed around the potometer temp- put potometer in a colder or warmer room Light intensity- put potometer in a dark cupboard or use a lamp. |
| photosynthesis and respiration | light energy - chemical energy sotred in bonds of glucose- released in respiration- chemical energy used to create large molecules like proteins , and heat energy is used to maintain a steady body temperature |
| Respiration | uses oxygen made a a waste product of photosythesis. co2 always enter the leaves becasue there is always a higher conc of it outside than inside the leaf as the leaves constantyl use it in photosythesis |
| Factors affecting rate of diffusion | Surface area to volume ratio Temperature Concentration gradient- does not affect active transport |
| How leaves are adapted for gas exchange- different to how leaves are adapted to photosynthesis | thin- short diffusion distance large surface area- for diffusion stomata- close when soil is dry, or when it is dark, so water is not lost. air spaces- gases can diffuse easily lots of stomata- gases to diffuse easily |
| stomata | close when dark- no photosythesis so no co2 required- reduces water loss by transiratino close when soil is dry- less water available for them to drw up from soil, so need to close to save water- die becasue they cannot photosynthesize. |
| guard cells | control the opening and closing of the stomata |
| how alveoli are specialised for gas exchange | increase the surface area of lungs greatly. moist lining - gases to dissolve in alveoli have very thin walls- short diffusion distance rich blood supply- maintain steep concentration gradients walls are permeable- gases can diffuse across easily |
| Smoking tobacco | Nicotine- addivtive drug carbon monoxide- binds to haemoglobin- stillbirths and smaller babies tar- cause cells to mutate to form cancer in in lungs and in throat tar-damage cilia- dirt and pathogens are not swept away so infections are results emphysema- when walls of alveoli become large and irregular making diffusion of gases less efficient as surface area is reduced tobacco smoke contains carcinogens- chemicals that can cause cancer tar irritated bronchioles- smokers cough |
| how smoking can cause coronary heart disease | due to co3 binding to haemoglobin, heart rate increases to deliver more oxygen to cells more quickly , which leads to increase in blood pressure. high blood pressure damages artery walls, making formation of blood clots more likely- risk of cornary heart disease increases |
| Experiments | Reliability-repeats at least three times Validity-repeats and fair test Fair test- only have one independent variable |
| The need for a control variable | In some experiments it is too hard to control all of the variables other than the independent variable, so having a control allows you to see what happens when you change nothing at all |
| reliability | repeat experiment three times and take a mean or an average |
| anomalies | ignore anomalies when calculating an average |
| graph know how | independent variable goes on x axis if data is continuous- e.g temp- use a line graph if data is discrete- categoric- use a bar chart, and have spaces in between |
| Evaluating a conclusion | say whether the evidence from the experiment supports the conclusion |
| reducing risks of fire | put bunsen burner on hear proof mat |
| how to improve accuracy and precision | usually need to change your method- e.g use a gas syringe instead of counting number of bubbles produced as these could be different sizes and you may miss some bubbles when counting if produced quickly |
| precision | use more sensitive apparatus intruments like mm ruler not cm ruler measure to 3 sf not to nearest whole number |
| pesticides | give a very high yield easy to apply increase profits a lot are not specific often poisonous to humans affect food chains pests can develop resistance can be leached into rivers, but do not cause eutrophication |
| biological control | no harm to environment highly specific- not affect food chains long lasting natural predators can become pests themselves |
| Fertilisers | needed to replace elements that are missing from the soil, because previous crops used them up provide more of these elements that are important eg nitrates, |
| Methods of increasing crop yields | artifically creating ideal conditions for photosynthesis fertilisers biological or chemical pest control |
| biological control | using other organisms to reduce the numbers of pests predators disease causing parasites |
| Plasma | Digested food molecules- glucose and amino acids hormones heat energy urea from liver kidneys- where it is removed carbon dioxide |
| Platelets | small fragments of cells that help blood clot stops you losing too min blood, and prevents micro-organisms from entering the wound mesh of fibrin (protein) forms, which holds platelets together. this process needs other clotting factors too though |
| Red blood cells | biconcave- large surface area for absorbing and releasing oxygen. no nucleus- more space for more haemoglobin- so more oxygen can be carried contain haemoglobin- contains lots of iron- gives red colour |
| Haemoglobin | Binds with oxygen to form oxyhaemoglobin in lungs. In body tissues, oxyhemoglobin converts to oxygen and haemoglobin - releasing oxygen into cells |
| Function of immune system | deals with pathogens- cause disease immune system needs to respond quickly so that the pathogens do not reproduce rapidly |
| Phagocytes | ingest pathogens- by engulfing them non specific- so they attack anything that it not meant to be there |
| lymphocytes | produce antibodies that are specific to the surface antigens -label them antibodies are then produced rapidly and flow around the body to mark all similar pathogens |
| memory cells | form when some of the lymphocytes stay around in the the blood after the original infection was fought off. makes us immune to most diseases because the body has a memory of what the antigen was like, so can produce loads of antibodies to label the antigens before it infect you- quick |
| P2- Vaccination | Needed because it can take a while for body to produce lymphocytes to label the antigens inject dead or inactive pathogens- carry harmless antigens but they still trigger immune response lymphocytes produce antibodies to attack them some of these lymphocytes remain in blood as memory cells, so if body is infected with the same pathogen, they can produce antibodies quickly to fight off pathogen before it can multiply and make you il. |
| Capillaries | involved in the exchange of materials at the tissues |
| valves in veins | keep blood flowing in the right direction- prevents back flow of blood |
| Arteries and veins | Pulmonary artery is the only artery that carries deoxygenated blood away from the heart Pulmonary vein is the only vein that carries oxygenated blood towards the heart |
| Exercise increases heart rate | muscles need more energy so respire more- blood needs to be pumped round body faster to deliver oxygen so heart rate must increase receptors in aorta detect high levels of co2 in blood. send signals to brain brain sends signals to heart, causing it to contract more frequently and with more force |
| Hormonal system helps to control heart rate | body is threatened Adrenal glands release adrenaline- binds to specific receptors in heart- causes muscles to contract more frequently and with more force- so heart rate increases and heart pumps more blood. increases oxygen supply to tissues- getting body ready for action |
| Types of systems | digestive circulatory respiratory reproductive excretory |
| circulation sytem | made up of heart and blood vessels |
| ways of remembering structure of circulatory system | hepatic- liver renal- kidney pulmonary- heart |
| Exctretion- refer to notes | revise this section but none is paper 2 |
| CNS | coordinates a response response requires a stimulus, receptor and effector |
| neurones | transmit information using high speed electrical impulses |
Want to create your own Flashcards for free with GoConqr? Learn more.