biology Flashcards
1.1 why do companies use fructose rather than glucose
- cheaper
- easier to obtain
- relatively healthier
- more soluble
1.2 how do you test for sugar and what is the positive result
-using benedicts solution and placing it in a hot water bath.
-if it turns brick red, sugar is present.
1.3 how do you test for protein and what is the postive test for it
-using biurets solution and adding 5cm³ of the food molecules
-purple result for postive test
1.4 how is protein digested
-protein is broken down by the enzyme protease
-protease is released from the stomach, pancreas and small intestine.
-the product of this reaction are amino acids.
-the stomach digests protein as the hydrochloric acid has the optimum pH for it, this will speed up the process of digestion.
1.4 how is fat digested
-fat is broken down by the enzyme lipase which is released from the small intestine and pancreas.
-the products of this reaction are fatty acids and glycerol.
-as bile is released into the small intestine, the bile will emulsify fat forming small droplets with a large surface area for the lipase to work on causing quicker digestion.
2.3 what is the percentage change equation
percentage change= (v²-v¹)/v¹ ×100
(change)
3.1 what type of microorganism causes measles
virus
3.2 how can we reduce the spread of measles
- isolate
- wash your hands
- cover your mouth when coughing/sneezing
3.3 describe how the measles vaccine helps a person become immune to the measles pathogen
- a dead or inactive form of the measles pathogen will be injected into the body
- lymphocytes will be stimulated to produce specific antibodies for the pathogen
- if the pathogen re-enters the body, these antibodies will then be produced quickly to prevent further illness.
3.4 how does virus cause illness
-the virus will reproduce inside an organisms cells.
-this can damage or destroy the cells.
3.5 why do we need clinical trials
- toxicity, will it harm
- efficacy, does the drug work
- dose, what is the optimum amount to give a patient
4.1 what is the word and symbol equation for photosynthesis
word:
-carbon dioxide+water → glucose+oxyen
symbol:
-6CO2 + 6H2O → C6H12O6 + 6O2
4.2 describe the effect of increasing temperature on the rate of photosynthesis
(links to 4.3- explain why no gas was produced by the plant at 45C°)
- the rate of photosythesis will be high as the temperature increases until it reaches its optimum temperature.
- (4.3) but then, once the temperature gets too high, the enzymes will quickly denature, decreasing the rate of photosynthesis.
4.6 which tissue in the cut stem will differentiate into new root cells
meristem
5.2 how are prokaryotic cells different to eukaryotic cells
- eukaryotic cells have a nucleus and prokaryotic cells have a dna loop + plasmids
- prokaryotic cells are smaller
- prokaryotic cells are unicellular- single celled
5.3 how do you work out magnification
- magnification= size of image/actual size
- measure the scale bar image (beside drawing) in mm.
- convert to µm (multiply by 1000).
- magnification = scale bar image divided by actual scale bar length (written on the scale bar).
6.1 lung cell dividing- describe the cell cycle
- the cell grows bigger, the DNA duplicates and the chromosones are replicated.
- mitosis will occur, a set of chromosones are pulled to each end of the cell.
- the nucleus divides to form two nuclei.
- the cytoplasm and cell membrane divide and then two identical daughter cells are formed.
6.2 what is a malignant tumor
-cancerous tumors that invade neighboring tissues and spread to the parts of the body (metastasis) forming secondary tumors.
6.3 why would a smoker breathe faster when excercising than a non-smoker
-a non-smoker would have a larger alveoli surface area therefore the rate of diffusion is increased.
-a smoker would have a build up of tar in their lungs, breaking down the walls of the alveoli creating a smaller surface area, meaning less gas exchange will occur leading to less oxygen being able to get the bloodstream
7.0 a drug called gtn is known to relieve the symptoms of angina, explain the causes and symptoms of angina and how gtn reduces the symptoms of angina
-CHD is where fatty material is deposited in coronary arteries, this reduces blood flow so lack of oxygen pumped to body cells
-fatigue is due to the lack of oxygen in the cells
-GTN causes the coronary arteries to widen so more blood flow and oxygen being pumped around the body.
4.5 what happens when a greenhouse gets too hot
- the plants enzymes will denature
- the plant could loose moisture as the hot temperature could dry them out- transpiration (the hot environment will cause the water to evaporate too fast)
