Mixed Exam Style Questions Flashcards
Which valves is pushed open by oxygenated blood entering a ventricle?
Bicuspid Valve - two openings
What type of disease is malaria?
Parasitic
Explain discontinuous and continuous varation
Discontinuous variation is usually represented by bar graph. It is controlled by one or two genes and unaffected by the environment.
e.g. blood type
Continuos Variation is usually is represented with a histogram or a curve. It is controlled by a number of genes (polygenes) and are often influenced by environmental factors.
e.g. height
What piece of apparatus is used to determine the blood glucose concentration over a short time period following a meal
Biosensor
Why is it important to calibrate a colorimeter?
For accuracy and comparable data
What is the covalent chemical bond which links two cysteine amino acids
Disulfide
Name the molecule that is found in the cell walls of bacterial cells
Peptidoglycan
Describe what is happening when the ‘‘lub’ sound is heart?
Atrio Ventricular valves closing and blood leaving the ventricles
Describe what is happening when the ‘‘dub’ sound is heart?
The back flow of blood closes the semilunar valves in the aorta and pulmonary artery as the ventricles relax
Sucrose is a disaccharide.
What type of reaction occurs when broken down and what monosaccharides are produced?
Reaction - hydrolysis
Monosaccharide - alpha glucose + fructose
Sucrase is the enzyme that breaks down sucrose
Which of the bonds is broken by sucrase
Alpha glycosidic
The enzyme microtubule depolymerise is responsible for the breakdown of spindle fibres in mitosis.
Which phase has the highest number of active microtubule depolymerise enzyme?
Telophase
What test should become positive when amylase is tested?
Benedicts test
Biuret Test
An amylase is an enzyme that catalyses the hydrolysis of starch into sugars.
State two differences between a molecule of ADP and DNA nucleotide that contains adenine
ADP has two phosphate groups whereas DNA only has one phosphate group
ADP has a ribose sugar whereas DNA has a deoxyribose sugar
ADP binds with an inorganic phosphate to make ATP
Name this type of reaction
Condensation
Explain how the genetic code in the gene for tubulin codes for the protein tubulin
Each gene contains a codon which have 3 bases, which code for an amino acid.
The sequences of bases determines the sequence of amino acid and codes for the protein
Describe three cellular functions of the cytoskeleton apart from the formation of microtubules
Cytoskeleton provides shape and stability to the cell
Cytoskeleton helps with movement of organelles around the cell e.g. vesicles
Cytoskeleton provides mechanical strength to cells
Suggest two ways tubulin is essential to protein synthesis and protein secretion in eukaryotic cells.
Tubulin helps with the movement of mRNA from the nucleus to the ribosome on the rough endoplasmic reticulum
Tubulin helps with the movement of vesicles from the RER to the Golgi where the protein is check and repackaged
Explain how to measure the diameter of the nucleus of one of the WBC, when observing the cells through a light microscope
You will need a eyepiece graticule
Calculate for one eye piece unit
Then view the nucleus and find out the diameter in epu
Take repeat measurements and calculate a mean diameter
Use calibrated epu to calculate diameter of nucleus
Compare 3 microscopes:
- SEM
- TEM
- Laser Scanning
SEM - 3-10nm, 3D, black and white
TEM - 0.5nm, 2D, black and white
Laser Scanning - 200nm, 2D/3D, colour
DNA can be extracted from white blood cells
Explain why the cells do not need to be crushed before adding detergent
Do not have cell walls to break open
Suggest the type of enzyme that should be used to extract DNA from White blood cells
Hydrolytic enzyme as it breaks down histones
Explain why using standard deviation would increase the confidence in any conclusion made
Standard deviation shows the spread of data around the mean. It reduces the effect of an anomaly
Staphylococcus aureus is a bacterium
The graph shows the percentage of samples that were methicillin resistant (MRSA).
Suggest explanations for the positive correlation in the data in the graph
Over prescription of methicillin
Not completing the course
Natural Selection of MRSA
Staphlyococcus aureus is the binomial name for a species of bacterium
State one advantage of referring to staphylococcus aureus in this way
Universal Language
Explain the importance of maintaining biodiversity for the discover of new antibiotics
Plants are used to make drugs
It increases the chance of finding new drugs
Explain what is meant by personalised medicine and synthetic biology
Personalised medicine is medicine made catered to someones geneotype/gene
Synthetic Biology - is the synthesis of new genes
Explain how the structure of glycogen differs from that of amylopectin to make it better suited as an energy store in animals
Glycogen is more branched
More coiled
More compact so less space needed for storage
Describe the structure of alpha glucose and beta glucose
Alpha glucose has OH at the bottom on carbon 1
Beta glucose has OH at the top on carbon 1
State two differences between the closed circulatory system of the sea bass and the closed circulatory system of a mammal
Sea bass is single whereas mammal is double
Sea bass blood only goes through heart once, mammal blood goes through heart twice
Define the term closed circulatory system
Blood is moving within the vessels
Name two arteries that can be seen in a heart
Coronary artery
Pulmonary Artery
What is the inner dividing of the wall in the heart called and what does it do?
Septum
Separates oxygenated and deoxygenated blood
What is an extracellular enzyme
Works outside of the cell
Explain one advantage and one disadvantage of the lack of nuclei and other membrane bound organelles to mammalian erythrocytes
Advantage - large surface area so more uptake of oxygen
Disadvantage - no genetic material so cannot divide
Viruses do not use erythrocytes as host cells whereas the malarial pathogen Plasmodium spends part of its life cycle inside erythrocytes
Suggest Why
Virus is unable to replicate outside a host cell as it does not contain ribosomes for protein synthesis. Plasmodium uses erythrocytes as host cells to hide from the immune system
Explain why erythrocytes do not make use of any of the oxygen that are transporting
They lack mitochondria therefore no aerobic respiration
What name is given to a change in the oxygen dissociation curve due to increasing carbon dioxide concentration
Bohr Shift
With reference to the structure of blood vessels explain why oxygen is not released until the blood reaches the capillaries
Arteries have thick walls whereas capillaries have think walls. Diffusion distance is shorter in capillaries
Explain why the blood off loads more oxygen to actively respiring tissues than to resting tissues
In actively respiring tissue more CO2 is produced
CO2 results in dissociation of carbonic acid / increase of H+ ,
leading to the release of oxygen
Which ion:
is a cofactor for amylase
Prosthetic group for carbonic anhydrase
Cl-
Zn 2+
Name a primary defence mechanism against pathogens
Blood clotting
Describe how a neutrophil looks like
Multi lobed nucleus
Describe how the structure of each blood vessel is adapted to its function. (6 marks)
Artery - carries blood away from the heart under high pressure
It has a thick elastic layer which enables them to withstand pressure, as well as stretch and recoil. It has collage which maintains shape and provides structural support. Smooth muscle contracts and relaxes to change the size of the lumen.
Veins - carries blood back to the heart, moving against gravity
Thin elastic band, has valves to prevent back flow, more collagen to give structural support
Capillaries - allows substances to be exchanged
Walls are one cell thick so short diffusion distance
Only large enough to allow red blood cells to travel through
How can PBO acts as an enzyme inhibitor
It is non competitive
the PBO binds to the allosteric site causing the active site to change shape and a substrate can no longer fit into it
State two features of organisms that belong to the kingdom Protoctista
Eukaryotic cells, Linear DNA
Explain how a pitfall trap can be used to set up and used to sample invertebrate biodiversity.
Dig a hole and place a container in the soil
Cover to protect from rain
Leave overnight
Identify number of invertebrates
Many birds are found in moorland habitats, they are red listed and is a high level of concern
Suggest measures that could be implemented to protect the biodiversity of moorland habitats.
Education
Habitat Restoration
Captive Breeding Programmes
Give area/red listed species a protected status
What products are formed
The enzyme thromboplastin + prothrombin =
The enzyme thrombin + fibrinogen =
Thrombin
Fibrin
