Exam questions Flashcards
(71 cards)
Which of the following is visible to the naked eye: AV valve Bundle of His left ventricular wall Pulmonary vein Purkyne fibres SA node Semi-lunar valve Septum
AV valve
left ventricular wall
Semi-lunar valve
Septum
Explain why the answer calculated in part (i) may not be an accurate repressentation of the patient’s heart rate and suggest hoe a more accurate answer could be obtained
Only one full cardic cycle shown, so it could be an anomalous
measurement of cycke from different points gives different values
A mean would be better
Digoxin caused the heart rate to change. Identify one other effect of dioxgin
londer T-wave
Explain why phenolphthalein indicator was able to detect the breakdown of triglycerides
The breakdown product is fatty acid. The pH falls as more breakdown occurs
Standard deviation is measures of the spread of results. All significant variables were controlled during the investigation. Identify a limitation of the experiment procedure that caused a high standard deviation and suggest an improvement to the methos that could reduce this spreed of results
limitation: The end point is diffucult to judge
Improvement: USe a pH meter
Tryglycerides contain three elements
C55H98O6 = M C18H30O16 = N
Which of rhw formule coresponds to a triglyceride, and why?
Formula: M
Because: hgih ration of hydrogen and oxygen, approximately 2H : 1O
phospholipid molecules are similar to triglycerides but they also contain the element phosphorus as part of a phosphate group.
Explain how the structure of phospholipids allows them to form the bilayer of a plasma membrane
Hydrophilic head and hydrophobic tail
Hydrophobic tail repelled by water
head forms H-bonds with water
Medium outside and inside the plasma membrane is aqueous
Hydrophobic nature of tail result in their facing towards each other
The plasma membrane also contains proteins, which are made within the cell. Outline the process and the organelles involved in the translation of these proteins fro RNA
(m)RNA transorted out of nucleus
(m)RNA transported to ribosome
Protein synthesis occurs at ribosoe
(t)RNA brings specific amino acids
Peptide bonds form between adjacent amino acids
Polypeptide procesed through Golgi apparatus
After being mixed with iodine, which od the following show a blue/black colour? potato tuber cells erythroctes sieve tube elements neurophils
Potato tuber cells
Which of the folloing is not a role of an intracellular molecule?
cell to cell signalling
partially permeable barrier
site of chemical reactions
transport of substances across the membrane
Cell to cell signalling
Outline how the difference in human size between arteries and veins is related to their functions
In arteries small lumen maintains pressure
In veins low resistance needed because of low pressure
larger cross section compared to circomference means fewer particles ith low resistance
The wall of blood vessels contain a polymer called collagen. Name the type of monomer from which collagen is made and explain how teo such monomers are joined together
Name: Amino acid
Join together by: Peptide bond between amino group and carboxyk group of different amino acid. Water is produced
How have gills adapted for efficient gas exchange?
Many lamella, provides a large SA
Pressure of secondary lamellae on main lamellae provide large SA
Short distance between blood and water. Blood maintains steep consentration gradient
Faster diffusion of oxygen
Each gill is supported by a gill arch made of bone, Bone tissue and gills are describe as organs
A tissue has one type of cells and performs one function
Bone has 1 type of cell
Organs consists of several tissues
Gills contain bone and blood
Explain why it is important for the survival of the llama haemoglobin dissociation curve is the left of the camel haemoglobin dissociation curve
Llama haemoglobin need higher affinity for oxygen so that it can pick up oxygen at lower partial pressure of oxygen
Describe how the structure of llama haemoglobin is likely to be differnt from that of camel haemoglobinwih reference to the four level of protein struture
Difference in primary structure:
difference amino acid
One amino acid change
Amino acid change could cause change to the secondary structure:
initial coiling or folding of polypeptide chain
alpha helix, beta pleated sheat
hydrogen bonds
Amino acid chase cause change in the terry structure: Further coiling of secondary structure ionic bonding, disulphide bonding hydrophobic and hydrophilic bonds 3D shape
Amino acide change does not change quaternary structure:
alpha and beta still able to form haemoglobin in both camel and llama
Three properties of collagen
insoluble
strong
unreactive
A vet is concerned that a llama is unwell. The vet suspects there may be haemoglobin in the urine of the llama. Explain how the vet could confirm this suspicion?
observe colour change from blue to purple
compare wth bank/control urine contain no protein
Explain how pairing of nitrogen bases allows identical copies of DNA to be made
Adenine with thymine and cytosine pairs with guanine
because of hydrogen bonding
purine can only bind with pyrimidine because are different sizes
Outline how the process of DNA replication is completed, following the pairing of nitrogenous bases
DNA polymerase
sugar-phosphate backbone forms between phosphate and sugar
DNA winds into double helix
Why is DNA replication described as semi-conservative?
New molecule consists of 1 old stand and 1 new strand
Which of the following causes the first ‘lub’ component?
Closing of the atrioventricular valves
What can you observe under a light microscope?
Whole cells and tissues
What can you observe under a transmission electron microscope?
Organelles
