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WorksheetsBiology A level AQA Unit 6
Total questions: 19
Worksheet time: 28mins
The diagram shows a motor neurone. Which line shows the correct function of the labelled parts?
A
B
C
D
2. The diagram shows some biochemical pathways in a liver cell, some of which are reversible. Five reactions whose rate in a certain direction can be changed by the presence of a hormone are labelled 1 – 5.
Each number relates to the direction of the arrow nearest to the number. Which numbered reactions have their rate increased in the presence of insulin?
1
2
3
4
5
A sudden movement close to the eyes causes a person to blink. Which line summarises the events involved in this response?
A
B
C
D
The diagram shows part of a myofibril of skeletal muscle. There are 4 000 identical sarcomeres in the myofibril and each one contracts until the myosin filaments are just touching the Z lines.
By how much will the whole myofibril shorten during contraction?
1600 μm
3000 μm
3.2 mm
4.6 mm
Glucose moves from the filtrate in the nephron into the bloodstream during normal kidney function.
What part of the nephron allows this movement of glucose, and by what mechanism?
collecting duct by active secretion
distal convoluted tubule by facilitated diffusion
glomerulus by ultrafiltration
proximal convoluted tubule by selective reabsorption
Homeostasis maintains optimum concentrations of chemicals in tissue fluid and blood plasma, so that reactions can function optimally in cell cytoplasm. The diagram shows the concentrations of three different ions and the concentration of protein measured in these three constituents. Which line correctly identifies 1, 2 and 3?
A
B
C
D
What will increase the secretion of anti-diuretic hormone from the posterior pituitary gland?
decreasing the external temperature of the body
drinking a large volume of water
Injecting a concentrated salt solution with low water potential into the body
Injecting a dilute glucose solution with high water potential into the body
A glucose tolerance test can be used to investigate a person’s ability to homeostatically adjust their blood glucose concentration. The concentration of glucose in the blood plasma is measured before and after consuming 50 g glucose. The table shows plasma blood glucose concentrations before and during a glucose tolerance test that are diagnostic of different conditions. Results from glucose tolerance tests for three individuals are shown on the graph. Which line correctly diagnoses each individual's condition?
Hepatocytes carry out a number of different functions.
Which statement(s) describe functions that occur in hepatocytes?
Combining ammonia and carbon dioxide via the ornithine cycle
Storage of glycogen and some vitamins and minerals
Breakdown of drugs and alcohol
A decrease in environmental temperature causes changes in the physiological functioning of the skin.
Which line of the table identifies the changes that occur?
A
B
C
D
Neurones are electrically excitable cells that experience changes in the electrical potential differences across their membranes. Particular potential difference values or changes are identified by the terms resting potential, threshold potential and action potential.
Which statements are true of these terms?
Action potential describes a rapid reversal in potential difference.
Resting potential and threshold potential are negative values.
An action potential begins before threshold potential is reached.
Which line of the table identifies a neurone that is at resting potential?
A
B
C
D
The diagram shows the homeostatic control of the glucose concentration in the blood of a mammal. Which line of the table identifies the hormones W, X and Y?
A
B
C
D
A certain poison kills by causing paralysis of the breathing muscles. When the poison is present, the sarcolemma at the neuromuscular junctions cannot depolarise.
Which option(s) could explain the action of this poison?
It prevents the release of acetylcholine.
It blocks acetylcholine receptors on the sarcolemma.
It inhibits the action of acetylcholinesterase.
Which statements are true of feedback systems in the body?
Negative feedback acts to reverse a change.
An example of negative feedback occurs when a high plasma concentration of a hormone inhibits further secretion of that hormone
Positive feedback occurs during the generation of an action potential.
Different regions of the kidney nephron have different functions. Which line of the table identifies:
· The region that reabsorbs the most water from the filtrate
and
·A region that has receptors for the hormone ADH?
A
B
C
D
Motor neurones in the vagus nerve cause responses in the heart, lungs and digestive organs.
In which divisions of the nervous system can the motor neurones of the vagus nerve be classified?
autonomic nervous system
peripheral nervous system
central nervous system
A synapse is a junction between two neurones, the presynaptic and postsynaptic neurones.
Which statements identify correct combinations of presynaptic and postsynaptic neurones at synapses?
A presynaptic sensory neurone synapses with a postsynaptic motor neurone.
A presynaptic relay neurone synapses with a postsynaptic relay neurone.
A presynaptic relay neurone synapses with a postsynaptic sensory neurone.
The fight or flight response involves a large number of coordinated changes in the functioning of the body of a mammal.
Which systems are involved in bringing about the fight or flight response?
The autonomic nervous system.
The endocrine system.
The cyclic AMP second messenger system.
