things idk Flashcards
(14 cards)
The secondary structure of a polypeptide is produced by bonds between
amino acids.
Describe how.
Hydrogen bonds
Between amine group and carboxyl group
Forming B pleated sheet and alpha helix structure
Two proteins have the same number and type of amino acids but different
tertiary structures.
Explain why.
Different amino acid sequence
Which forms hydrogen bonds in different places
4.73% of the patients who had taken medicines containing high
sodium concentrations suffered from hypertension
* there were 7.18 times fewer control patients with hypertension.
Calculate how many of the control patients had hypertension.
8514
A high concentration of sodium in the blood can affect blood volume and
cause hypertension.
Use your knowledge of water potential to suggest how high sodium
concentrations in the medicines taken could affect blood volume.
Sodium ions lower water potential of blood
Water moves into the blood by osmosis
Increasing blood volume
Describe the roles of iron ions, sodium ions, and phosphate ions in cells.
Iron ions
Haemoglobin binds/associates with oxygen
OR
Haemoglobin transports/loads oxygen;
Sodium ions
Co-transport of glucose/amino acids (into cells);
(Because) sodium moved out by active transport/Na – K pump;
Creates a sodium concentration/diffusion gradient;
Affects osmosis/water potential;
Phosphate ions
Affects osmosis/water potential;
Joins nucleotides/in phosphodiester bond/in backbone of
DNA/RNA/in nucleotides;
Used in/to produce ATP;
Phosphorylates other compounds (usually) making them more
reactive;
10. Hydrophilic/water soluble part of phospholipid bilayer/membrane;
Outline the role of organelles in the production, transport and release of proteins from
eukaryotic cells.
Golgi Appartus
they add carbohydrates to proteins to make glycoproteins
they form lysosomes
Ribosomes /RER
Protein synthesis
Mitochrondia
Site of aerobic respiration
produce ATP for protein synthesis
DNA in nucleus codes for protein
Explain a property of iron ions that enables these ions to carry out their role in red
blood cells.
are positively charged which allows them to bind to o2 and allows the formation of oxyhaemoglobin
describe the important of mcielles in absorbing lipids into the epithelial cells of the ileum
micelles are made of bile salts, fatty acids and monoglycerides
micelles make fatty acids more soluble in water
micells carry the fatty acids to the epithelial cells of the ileum
fatty acids are absorbed into the cells of the ileum by simple diffusion
Explain how sucrose-transport proteins in leaf cells enable the production of a
pressure gradient in the phloem.
sucrose is actively transported by cotransport into the phloem
this decreases/lowers water potential
water moves in by osmosis from the xylem
Potato plants with fewer sucrose-transport proteins produce fewer potatoes and
accumulate sugars in their leaves (lines 4, 5 and 6).
Explain why.
less sucrose being transported to phloem
Less sucrose transported to sink/potato/root
Describe the role of enzymes in the digestion of proteins in a mammal.
(Reference to) hydrolysis of peptide bonds;
Endopeptidase act in the middle of protein/polypeptide
OR
Endopeptidase produces short(er) polypeptides/ increase number of ends;
Exopeptidases act at end of protein/polypeptide
OR
Exopeptidase produces dipeptides/amino acids;
Dipeptidase acts on dipeptide/between two amino acids
OR
Dipeptidase produces (single) amino acids;
The food eaten by a rabbit is digested mainly by microorganisms in its caecum. The
caecum is a section of intestine attached between the ileum and the large intestine. The
resulting semi-digested material leaves the anus of a rabbit as soft, caecal droppings. The
rabbit then eats these caecal droppings.
Use this information and Figure 2 to suggest how eating its own caecal droppings helps a
rabbit’s digestion and absorption of dietary protein.
More/remaining/undigested (protein) broken down;
Accept all (protein) broken down
(So more) amino acids absorbed;
(Because) protein/food passes again through stomach/ileum;
The addition of a respiratory inhibitor stops the absorption of amino acids.
Use the diagram to explain why.
No/less ATP produced
OR
No active transport;
Sodium (ions) not moved (into/out of cell);
Accept: sodium (ions) increase in cell.
Accept: sodium (ions) cannot diffuse into cell.
No diffusion gradient for sodium (to move into cell with amino
acid)
OR
No concentration gradient for sodium (to move into cell with amino acid);
Describe the role of the enzymes of the digestive system in the complete breakdown of
starch.
Amylase;
(Starch) to maltose:
Maltase;
Maltose to glucose;
Hydrolysis;
(Of) glycosidic bond;
