Nucleic Acids Flashcards
describe how ATP is resynthesised in cells
from adp and phosphate
by ATP synthase
during respiration/photosynthesis
give two ways the hydrolysis of ATP is used in cells
to provide energy for other reactions
to add phosphate to other substances and make them more reactive it change shape
what is evidence of Scanning electron microscope
can see a 3D image
what is the bond between phosphate and Penrose sugar called
phosphodiester
describe the function of DNA helicase
breaking hydrogen bonds
describe the function of DNA polymerase
joins nucleotides by forming phosphodiesterase bond
Compare ATP and DNA
ATP has ribose and DNA nucleotide has deoxyribose
ATP has 3 phosphate groups and DNA has 1
ATP, base always adenine and in in DNA bases can vary
describe the link between oxygen concentration, rate of respiration and rate of uptake of potassium ions
greater rate of oxygen consumption leads to greater rate of respiration and greater rate of uptake
oxygen required for respiration
respiration produces ATP/releases energy
pottasium ions taken up by active transport which requires energy
explain decrease in the vegetable disk size when placed in water
water potential inside potato higher
water moves out by osmosis
other than ethical reason, why would you choose animals such as cats?
1 are mammals so likely to have same physiology as humans
2 small enough to keep in laboratories
3 can use in large number
why can monitoring the pH of mixture show that lipids are present in a substance (when the lipase is added to substance)
hydrolysis of lipase produces fatty acids
this lowers pHl
describe how you can use emulsion test to show seed contains lipids
crush DO NOT ADD WATER
dissolve into alcohol
add water AFTER
White emulsion shows presence of lipid
does correlation show causation?
no, perhaps a third factor
how to work out number of water molecules produced from a diagram
count number of Xs and Rs
why are hydrogen bonds important for cellulose?
holds chains together by forming cross links which forms microfibrils providing strength
hydrogen bonds are strong in large numbers
why is the shape of a starch molecule important to function in cells
spiral shape which makes it compact
explain two ways fatty acids are important to formation of new cells
fatty acids used to make phospholipid
phospholipid in membranes
more phospholipids more membranes made
fatty acids respired to release energy
more triglycerides, more energy released
energy used for cell production
other than being smaller give two ways in which prokaryotic DNA is different from Eukaryotic DNA
prolaryotic dna has cirular/non linear DNA
is not associated with proteins
no non coding DNA
how is the dna of a virus different from that of other organisms
usw knowledge of dna to suggest the difference
in virus dna A does not equal T neither does equal to C
so no base pairing
dna is not double stranded
during replication, nucleotides can be added only in a 5’ to 3’ direction, explain why
dna polymerase
is specific
so only complementary with 5’ end
shape of 5’ is different from 3’ end
explain why maltase catalyses the hydrolysation of maltose
active site has specific shape
this is complementary to substrate(maltose)
so only maltose can bind
to form an enzymesubstrate complex
explain the structure of cellulose and how it’s adapted for it’s function in cells
1 made from β glucose 2 joined by condensation 3 1:4 link 4 flipping over alternate molecules 5 hydrogen bonds linking long unbranched straight chains, this collectively adds to the strenght 6 cellulose makes cell wall strong 7 can resist turgor pressure 8 bonds difficult to break 9 resis digestion
