Homeostasis, 171

Front 1

What are the four categories into which all bio molecules can be divided into ?

Back 1

1. Proteins
2. Carbohydrates
3. Nucleotides
4. Lipids

Front 2

True or False: All bio molecules are solely composed out of carbon, hydrogen, oxygen and nitrogen.

Back 2

False. Some bio molecules can be comprised of other elements such as iron which makes hemoglobin.

Front 3

Give the general template for all physiological control systems.

Back 3

1. Stimulus
2. Sensor/ Receptor
3. Afferent pathway
4. Integrating center
5. Efferent pathway
6. Effector
7. Response

Front 4

What is the difference between an afferent and efferent pathway ?

Back 4

An afferent pathway moves information from the sensor to the integrating system and the efferent pathway moves the stimulus for the response to the effector.

Front 5

True or false: The integrating center is always located locally with respect to the sensors.

Back 5

False. The integrating center can be located locally with respect to the sensors (e.g. pancreas beta cells) but can also be located at another position away from the sensors (e.g. thermoreceptors' integrating system we find in the brain).

Front 6

Which pathways do sensory neurons make use of ?

Back 6

Afferent pathways.

Front 7

Which pathways do motor neurons make use of ?

Back 7

Efferent pathways.

Front 8

What are the two main categories motor neurons can be divided into ?

Back 8

1. Autonomic
2. Somatomotor

Front 9

Define a sensor/receptor.

Back 9

Specialized structures that convert stimuli into electrical signals.

Front 10

True or false: The hypothalamus is an example of an integrating center.

Back 10

True.

Front 11

Name the two different feedback loops with regards to stimulus.

Back 11

1. Negative feedback loop
2. Positive feedback loop

Front 12

Define negative feedback.

Back 12

A feedback loop where the response to the stimulus tries to counteract the stimulus itself, thereby shutting off the stimulus.

Front 13

True or false: Once a signal from the afferent pathway has reached the integrating center, it will always formulate a response.

Back 13

False. The integrating center compares the stimulus to a genetically predetermined set point, if the stimulus causes conditions to exceed or fall below the set point, it will formulate a response to compensate for the change.

Front 14

Describe what a set point is in terms of homeostasis.

Back 14

It is a genetically predetermined set point for optimal physiological function.

Front 15

Name the two stimuli for beta cell stimulation.

Back 15

1. Increased blood glucose
2. Stretch receptors in the stomach

Front 16

Which three tissues have receptors for insulin to bind two ?

Back 16

1. Liver tissue
2. Muscle tissue
3. Fat tissue

Front 17

What are the effects on physiology when glucagon is secreted ?

Back 17

1. Increases blood glucose
2. Glycogen catabolism
3. Lipid catabolism
4. Stimulates glucogoneogenesis
5. Stimulates ketogenesis

Front 18

Define the term gluconeogenesis.

Back 18

The creation of glucose from non-glucose precursor molecules.

Front 19

Which hormone dominates during the fed state with regards to blood glucose ?

Back 19

Insulin.

Front 20

Which hormone dominates during the fasting state with regards to blood glucose ?

Back 20

Glucagon.

Front 21

Define positive feedback.

Back 21

The response of the positive feedback reinforces the stimulus, thus sending the parameter farther from the set point.

Front 22

Give an example of a negative feedback system.

Back 22

1. Control of blood glucose levels
2. Temperature control of the body
3. Dehydration

Front 23

Give an example of a positive feedback system.

Back 23

1. Birth

Front 24

Which hormone induces contractions during birth ?

Back 24

Oxitocin.

Front 25

Which gland secretes oxitocin ?

Back 25

The posterior pituitary gland.

Front 26

True or false: The positive feedback system requires an external factor to close off the feedback loop.

Back 26

True.

Front 27

Define a compartment.

Back 27

A fluid filled space surrounded by a selectively permeable membrane.

Front 28

Name the three fluid compartments of the body.

Back 28

1. Intracellular fluid
2. Interstitial fluid
3. Blood plasma

Front 29

Which two compartments collectively form the compartment referred to as the extracellular fluid ?

Back 29

1. Interstitial fluid
2. Blood plasma

Front 30

True or false: The fluid compartment that contains the most fluid with regards to the extrecellular space is the interstitial fluid.

Back 30

True.

Front 31

Which fluid compartment in the body contains the most fluid.

Back 31

The intracellular fluid compartment.

Front 32

Why do people refer to the extracellular fluid compartment as the most important compartment ?

Back 32

It allows for communication between the external environment and the intracellular fluid of cells.

Front 33

True or false: The extracellular compartment is also referred to as the internal environment.

Back 33

True.

Front 34

True or false: Physiological systems achieve homeostasis with the use of both positive and negative feedback systems.

Back 34

False. Homeostasis is solely achieved by making use of a negative feedback system.

Front 35

True or false: Osmosis occurs when water moves from a high osmolarity to a low osmolarity.

Back 35

False. Osmosis occurs when water moves from a low osmolarity to a high osmolarity.

Front 36

What are the effects of the hormone ADH on the kidneys ?

Back 36

It causes them to retain more water.

Front 37

Which structures does the somatic motor neurons control ?

Back 37

Skeletal muscle.

Front 38

Which structures does the autonomic motors control ?

Back 38

1. Smooth muscle
2. Cardiac muscle
3. Endocrine glands
4. Exocrine glands
5. Adipose tissue

Front 39

True or false: Somatic motor neurons are controlled involuntarily.

Back 39

False. Somatic motor neurons are controlled voluntarily. Autonomic neurons are controlled involuntarily.

Front 40

Into which categories can autonomic motor neurons be divided into ?

Back 40

1. Sympathetic
2. Parasympathetic

Front 41

True or false: Sympathetic neurons stimulate and parasympathetic neurons inhibit.

Back 41

True.

Front 42

Describe how sympathetic neurons ultimately form a response.

Back 42

1. The integrating system sends an action potential along the preganglionic neuron
2. The action potential stimulates vesicles containing acetylcholine to release their content into the synapses
3. The acetylcholine diffuses across the synapses inside the round structure called the ganglion
4. The acetylcholine binds to nicotine receptors on the postganglionic neuron
5. This causes an action potential to propagate along the postganglionic neuron
6. The action potential stimulates vesicle containing noradrenalin to release their contents
7. Noradrenalin is released at the distal part of the postganglionic neuron
8. Noradrenalin binds to adrenergic receptors and thus a response has been formed

Front 43

List the differences between sympathetic and parasympathetic neurons.

Back 43

1. P- Inhibits
S- Stimulates
2. P- The second neurotransmitter is acetylcholine
S- The second neurotransmitter is noradrenalin
3. P- Muscarinic receptors
S- Adrenergic receptors

Front 44

List the two different adrenergic receptors and add where they are most likely to be found.

Back 44

1. Alpha adrenergic receptors- Blood vessels
2. Beta adrenergic receptors- The heart

Front 45

True or false: Once a sympathetic neruon is stimulated to release noradrenalin, its final effect on the heart would be to decrease its rate.

Back 45

False. Since the sympathetic nervous system stimulates it will ultimately increase the heart rate once it stimulates the receptors located at the heart.