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A level Biology: Post your doubts here!
- Thread starter XPFMember
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The primary sequence is the linear sequence of amino acids in that protein.It is specific for every protein
thank u alotHeyy man, first thing Viruses are are not living cells and they r just Proteins which require a hist in which they multiply so basically they do not have cell walls and antibiotics affect cell wall synthesis so they have no effect on viruses and as far as CO2 transport is concerned I advice you to go through Bohr's effect in addition to little bit Information of reactions of Co2 in redblood cells like formation of Carbonic acid and dissassociation of into HCO3-1 and H+ ions ....soo juss have an overall idea
hope this helped
.....haha im not a man ^_^
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I'm sorry I was too busy answerin the question ...no offencethank u alot
for example the making of polypeptides by DNA. where peptide bonds are built up that is a primary structure?
http://www.xtremepapers.com/papers/...nd AS Level/Biology (9700)/9700_w10_qp_23.pdf
Can someone tell me why in Q1. fig1.1, the label B is a protein not a cholesterol?
Can someone tell me why in Q1. fig1.1, the label B is a protein not a cholesterol?
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In case a live virus is used, it's attenuated, meaning it still has it's antigen but cannot cause the body harm. So, it is the most effective form of vaccination.
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Peptide bonds are always present between the amino acid, irrespective of the structural arrangement.
ok. And why does increased blood pressure increase the risk of coronary heart disease?
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Persistent high blood pressure damages the lining of the arteries, in order to repair the damage cholesterol is deposited at the site of damage but this results in the build up of plaque over time. The plague hardens the arteries and also causes narrowing. This process leads to atherosclerosis which eventually leads to coronary heart disease.
What do the phosphate heads of the phospholips do.And why despite being polar they dont allow polar molecules to pass through them?
In semi conservative replication, the two strands of DNA unwind and each serves as a template for a new double helix to form. This produces two DNA molecules which are exact copies of each other, this helps maintain the genetic stability of the organism, and prevents any mutations from occurring. I hope this is what they are asking for...you can check the mark scheme though...
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Remember that protein are big and scattered in the membrane and chloestrol are the ones with a phosphate head and and a wiggly tail in the phospholipid bi layer
Answer:
There is complementary base pairing in a DNA molecule/double helix, so the double helix unwinds to give two complementary strands of DNA. Each strand acts as a template for the synthesis a complementary DNA strand, so two new DNA double helices are formed with each double helix having one original strand and one newly synthesized strand.
Basically, the property which allows semi-conservative replication is complementary base-pairing/strands, so you have to mention that, followed by the result of semi-conservative replication.
What do the phosphate heads of the phospholips do.And why despite being polar they dont allow polar molecules to pass through them?Answer:
There is complementary base pairing in a DNA molecule/double helix, so the double helix unwinds to give two complementary strands of DNA. Each strand acts as a template for the synthesis a complementary DNA strand, so two new DNA double helices are formed with each double helix having one original strand and one newly synthesized strand.
Basically, the property which allows semi-conservative replication is complementary base-pairing/strands, so you have to mention that, followed by the result of semi-conservative replication.
Phosphate heads are responsible for the orientation of the phospholipid bilayer. In questions related to how the structure of a phospholipid allows it to form a bilayer, you have to mention that the phosphate heads are hydrophilic and therefore, water attracting so they face outwards towards the aqueous environment (cytoplasm, or fluid around the cell).
Phosphate heads are only a small part of the bilayer, the fatty acid/hydrocarbon, tails form the major part of the bilayer, which is the hydrophobic interior. This hydrophobic interior acts as a barrier to ions and polar molecules such as water. So basically, polar molecules can reach till the phosphate heads, but cannot pass through the hydrophobic interior of the bilayer!
Thx, its just that certain diagrams draw cholesterol as a rectangular block, but I wasn't sure if CIE did that too. I guess you're right I've only seen CIE using the phosphate + tail diagramRemember that protein are big and scattered in the membrane and chloestrol are the ones with a phosphate head and and a wiggly tail in the phospholipid bi layer
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Antyme mate
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I think you mean 'plaque'... with a 'q'... don't write 'plague', its something entirely different.