biology Flashcards
a drink company claims that a drink contains sugar, protein and fat.
glucose and fructose are different sugars
fsuggest two reasons why the drinks company uses fructose in the drink rather than glucose
dont refer to sweetness in your answer
frutcose might help with the preservation of the drink as it reduces growth of bacteria
describe how a student could test the drink for sugar
give the color of the postive result.
worth 3 mark
take a small amount of the drink and place it in a tube
add benedicts solution in a test tube and heat the mixture
for 5 minutes
results-blue to red
describe how the student could test the drink for protein
give the color of a positive result
2 marks
place a small amount of biuret’s solution in a testtube with the drink inside and see the color change
from blue to purple
what type of microorganism causes measels
virus
two ways spread of measles can be reduced?
put people in quaratine
encourgae hygenic practices like disinfecting surfaces
explain how viruses cause illness(2 marks)
viruses attack the immune cells which causes it to get weaker. viruses cause illness by disrupting cell function
new druhs must go through clinical trails before being licensed for use.
give three reasons why clinicals trials are needed.
to ensure the drug is safe for human use
to ensure if the drug is working as it should be
describe the effect of increasing temperature on the rate of photosynthesis
as the temperature increases, the rate of photosynthesis increases because of high collisions however once it exceeds the optimal temperature the temp decreases
suggest 2 reasons against using a heater set at 25 c in the greenhouse
it could exceed optimum temperature a
warmer conditions are also good for bacteria
what type of microscope was used?
light microcsope, because only it is capable of seeing bacteria
give three ways a prokaryotic cell is different from eukaryotic
they dont have a nucleus
they have a singluar starnd of dna
prokaryotic cells are generally smaller.
describe the process of mitosis
the cells grows and replicates its dna, preparing for division(inter phase)
chromosomes line up at centre
two of each chromosomes are pulled into opposite ends(mitosis)
The cytoplasm, organelles, and cell membrane of the mother cell are divided into two new cells(cytokinesis)
what is meant by malignant tumour
the tumor which has uncontrolled cell growth and division that is cancerous and can potentially break off and invade tissues
explain why person b breathes faster?
person b’s lungs are damaged by smoking which make them smaller and less effective
when person A can easily get yhe oxygen they need. however person b’s damaged lungs struggle to get enough ozygen. so their body has the breathe much faster to try and catch up.
person b also has a damaged alveoli which leads to redcued gas exchange.
