6.4-6.6

Question 1

What substance id secreted by type 2 pneumocytes for moisture

Answer 1

Surfactant

Question 2

When we exhale what happens to lung volume and pressure

Answer 2

volume down and pressure up

Question 3

Extremely thin cells that make up walls of alveoli

Answer 3

Type 1 pneumocytes

Question 4

what happens during inspiration and expiration

Answer 4

During inspiration, external intercostal muscles contract and internal intercostal muscles relax. During expiration, diaphragm relaxes and pressure in lungs increases

Question 5

what is the name of the two tubes that branch off the trachea

Answer 5

bronchi

Question 6

what is ventilation rate

Answer 6

number of breathes taken per minute

Question 7

what is tidal volume

Answer 7

volume of air that is moved into and out of lungs

Question 8

consequences of emphysema

Answer 8

Decreased alveolar surface area leads to less gas exchange and shortness of breath

Question 9

what process allows oxygen to move into the bloodstream from alveoli

Answer 9

diffusion

Question 10

what type of electrical impulses jumping from one node to the other what is this type of electrical impulse called

Answer 10

Saltatory

Question 11

Multiple choice question
What generates a nerve impulse on the post-synaptic membrane?

Answer 11

Neurotransmitter binding with receptor sites.

Question 12

what are the myelin sheath, schawnn cells and nodes of ranvier

Answer 12

The myelin sheath is the fatty layer. The myelin sheath is made up of a number of Schwann cells, each separated by a node of Ranvier. The dendrites are found protruding from the cell body of the neuron and their role is to receive impulses from other neurons.

Question 13

There is an influx of which ion into the synaptic knob triggering the vesicles containing neurotransmitter to move towards the presynaptic membrane?

Answer 13

Calcium ions flood into the synaptic knob which causes the vesicles containing neurotransmitter to move towards the presynaptic membrane. The vesicles then fuse with the membrane, releasing the neurotransmitter.

Question 14

Which term describes the minimum level to which a membrane must be depolarised in order for an action potential to be fired?

Answer 14

Threshold/Threshold potential

Question 15

What describes the phase of quick entry of sodium ions (Na+) into an axon during an action potential?

Answer 15

When voltage-gated sodium channels open sodium ions into the axon causing depolarisation. The diagram below shows the various stages of the action potential.

Question 16

Excess acetylcholine in the synaptic space is broken down into choline and acetate by acetylcholinesterase. What happens to the choline?

Answer 16

The choline is reabsorbed back into the membrane to recombine with acetate and produce acetylcholine to be used again.

Question 17

Through which process are neurotransmitters released from the synaptic knob into the synaptic cleft?

Answer 17

exocytosis

Question 18

The operation of the sodium-potassium “pump” moves:

Answer 18

The sodium-potassium “pump” moves three sodium ions out of the cytoplasm of the axon for every two potassium ions pumped in. It is responsible for the establishment of the resting potential.

Question 19

what happens during depolarization and repolarization

Answer 19

During depolarization sodium ions move in to the axon and during repolarization potassium ions move out of the axon.

Question 20

Neonicotinoids are compounds that used to be widely used on farms as effective insecticides. It appeared they were easily absorbed by plants and were present in pollen and nectar, killing honey bees. Scientists discovered that neonicotinoids affect the cholinergic synapses in the nervous system of insects, causing their paralysis and death. How do neonicotinoids affect the synapses?

Answer 20

Neonicotinoids bind to postsynaptic receptors in insects, preventing acetylcholine (a neurotransmitter in the nervous system of insects) from binding. If acetylcholine is unable to bind to the receptors, the synaptic transmission of impulse will be prevented. The consequences are paralysis and death.

Question 21

Refractory Period

Answer 21

The period of time during which the axon cannot be depolarised is referred to as the refractory period. The refractory period ensures that the nerve impulse only travels in one direction.

Question 22

Repolarization

Answer 22

potassium ions move out the neuron

Question 23

where is leptin secreted from

Answer 23

adipose tissue

Question 24

FSH and Progesterone during the first 7 days

Answer 24

Progesterone remains low while FSH increases

Question 25

Which hormone dropping begins the cycle of menstruation

Answer 25

Progesterone

Question 26

The pituitary gland reducing the amount of FSH being secreted during the follicular phase of the menstrual cycle is an example of what type of feedback

Answer 26

negative

Question 27

What are the effect(s) of high levels of FSH in the menstrual cycle?

Answer 27

FSH rises to a peak towards the end of the follicular phase (day 14). It stimulates the development of follicles and the production of estrogen by the follicle wall which in turn causes the thickening of the uterus lining.

Question 28

A hormone, X, stimulates body cells to consume more oxygen. It mainly affects cells in skeletal muscles, liver and brain. The hormone X regulates the body temperature. People with a deficiency of X feel cold all time and feel tired. What is the name of hormone X?

Answer 28

thyroxin

Question 29

From where in the pancreas are insulin and glucagon released? (Cell names are not needed).

Answer 29

Pancreatic Islets

Question 30

Positive or Negative feedback: If low thyroxin levels are detected, the thyroid is stimulated to release thyroxin which will slow down the basal metabolic rate

Answer 30

Positive

Question 31

IVF (in-vitro fertilisation) is a complex procedure involving several steps. The woman takes a drug that will inhibit production of FSH and LH. Instead, injections of hormones are given daily to stimulate several ovarian follicles to grow and develop. What are the concentrations of hormones given in these injections?

Answer 31

FSH will be injected in much higher concentration to stimulate the development of multiple follicles (not just one or two as happens during the menstrual cycle) in both ovaries. In contrast, LH will be given in a smaller dose, since it plays an important role in ovulation, not in the development of follicles.

Question 32

role of Corpus Lutem

Answer 32

The corpus luteum secretes progesterone to help maintain the lining of the uterus. It also secretes oestrogen, and the high levels of progesterone and oestrogen inhibit the secretion of FSH and LH.

Question 33

look

Answer 33

As follicles develop during the follicular phase of the menstrual cycle, they release oestrogen, which inhibits release of follicle-stimulating hormone (FSH). This is an example of negative feedback.