The Immune System

1) List three differences between B and T cells.

2) Vaccination is an example of what type of immunity?

a. Artificial active immunity
b. Natural active immunity
c. Artificial passive immunity
d. Natural active immunity
e. None of the above

3) When might suppressor T cells become necessary?

4) Describe the antigen presenting process in macrophages.
5) What are cytokines?

6) Describe the two ways macrophages of the innate immune system work to destroy a pathogen.

7) What are the similarities and differences between antigen receptors and antibodies?

8) List the three types of T cells.

9) What is the role of the MHC?

The Endocrine System

1) List the eight different endocrine glands.

2) Synthesis and release of steroid hormones follows a process called
a. Constitutive release
b. Regulated release
c. Endocrine release
d. Trophic hormone release
e. Exocrine release

3) Thyroid-releasing hormone is released from the _____, while thyroid-stimulating hormone is released from the ______.

a. Pituitary gland / Hypothalamus
b. Thyroid gland / Pituitary gland
c. Hypothalamus / Pituitary gland
d. Hypothalamus / Thyroid gland
e. Pituitary gland / Thyroid gland

4) Which hormone is NOT released from the pituitary gland?

a. Growth hormone
b. Prolactin
c. Luteinizing hormone
d. Insulin
e. Follicle-stimulating hormone

5) How do amino acid-derived hormones differ from peptide hormones?

6) The thyroid gland requires what atom for proper function?

a. Magnesium
b. Calcium
c. Iodine
d. Iron
e. Insulin

7) The primary function of the pineal gland is regulating

a. Metabolism
b. Bone growth
c. Circadian rhythm
d. Stress response
e. Mood

8) Describe the relationship between the hypothalamus and the pituitary gland.

9) Why is the receptor for the steroid hormones on the inside of the cell, while most peptide hormone receptors are located on the cell surface?

The Nervous System

1) Describe the two parts of the autonomic nervous system and what they control.

2) The brain sends its directions for motor movement to the _______ system.

a. Autonomic
b. Somatic
c. Nervous
d. Central nervous
e. Motor

3) The ______ is the site of neurotransmission.

a. Dendrite
b. Axon
c. Nerve
d. Synapse
e. White matter

4) Describe the transfer of information between the PNS and CNS as you see a snake and as you run away from the snake.

5) What is the difference between white and gray matter?

6) What makes up a nerve?

7) What is the difference between an axon and a dendrite?

8) Which is not a neurotransmitter?

a. Glutamate
b. Dopamine
c. Acetylcholine
d. GABA
e. All are neurotransmitters

9) What is the primary function of the forebrain?

Fitting It All Together

1) What are two ways the brain can talk to the immune system?

2) True or False. Cytokines are chemicals that solely activate the immune system.

3) What endocrine glands are involved in the HPA axis activity?

4) Too little of this hormone, or a resistance to it's activity, causes diabetes.

a. Glucagon
b. Pancreatic enzymes
c. Insulin
d. Myelin
e. Growth hormone

5) What is an autoimmune disease?

6) Multiple sclerosis starts out as an autoimmune disease targeted at ______.

a. Islet cells of the pancreas
b. The basal ganglia
c. Hormones
d. T cells
e. Myelin

7) Why does Parkinson's disease affect movement?

8) What is a common way to treat autoimmune diseases?

9) Type II diabetes often occurs in overweight people, and is caused by insulin ______.

a. Resistance
b. Secretion
c. Synthesis
d. Malfunction
e. Degradation

10) True or False. Type II diabetes is thought to result from an autoimmune disorder.

Possible Answers

The Immune System

1) List three differences between B and T cells.

B cells mature in the bone marrow whereas T cells mature in the thymus. B cells are a part of the humoral immune system, while T cells belong to the cell-mediated immune system. B cells produce antibodies and T cells do not.

2) Vaccination is an example of what type of immunity?
a. Artificial active immunity

Because vaccinations stimulate the body to make memory cells, but aren't a part of the immune system themselves, they provide a type of artificial active immunity.

3) When might suppressor T cells become necessary?
Suppressor T cells regulate and monitor the immune system. When too many B and T cells are active and the immune response is overactive, the suppressor T cells can quiet the response. Similarly, when a pathogen has been eliminated and is no longer a threat, suppressor T cells will quiet the activity of B and T cells because they are no longer needed.

4) Describe the antigen presenting process in macrophages.
During phagocytosis, when a macrophage ingests a pathogen, intracellular proteins will degrade the pathogen into smaller parts. If these smaller parts could be recognized by an immune cell, they are called antigens. With the help of MHC proteins, these antigens come to the cell surface. T cells recognize both MHC proteins and antigens as signals to attack an infected cell.
5) What are cytokines?
Cytokines are communication chemicals that are released from leukocytes to inform neighboring cells about an impending attack. They'll also help activate other immune cells.

6) Describe the two ways macrophages of the innate immune system work to destroy a pathogen.
Most macrophages are both phagocytes and granulocytes. Phagocytosis is the process where an immune cell engulfs a pathogen and brings it into the cell for degradation. Tiny pockets of potent killer chemicals inside granulocytes will burst when the cell recognizes an internalized pathogen. Release of these chemicals will further break down the pathogen, rendering it non-functional by interfering with cell division, for example.

7) What are the similarities and differences between antigen receptors and antibodies?
Both antigen receptors and antibodies have two binding site that recognize particular antigens. Antigen receptors are cell-membrane bound on both B and T cells, whereas antibodies are water-soluble and are free to circulate through the body.

8) List the three types of T cells.
Helper, Cytotoxic, and Suppressor T cells.

9) What is the role of the MHC?
The MHC is a group of proteins that are expressed on the cell surface of most immune cells. When a pathogen infects a cell and is consumed, it is broken down into smaller pieces, called antigens. The MHC couples with these smaller antigens and brings them to the cell surface. T cells recognize the MHC and antigen on the cell surface, and are able to attack that cell directly.

The Endocrine System

1) List the eight different endocrine glands.

Hypothalamus, pituitary gland, thyroid gland, pancreas, adrenal medulla, adrenal cortex, pineal gland, and gonads (includes the testes in males and the ovaries in females).

2) Synthesis and release of steroid hormones follows a process called

a. Constitutive release
Constitutive release involves made-to-order hormones, while regulated secretion describes the process of simply releasing stored hormones whenever they are needed. The other three options do not describe hormone secretion processes.

3) Thyroid-releasing hormone is released from the _____, while thyroid-stimulating hormone is released from the ______.

c. hypothalamus / pituitary gland
Among other hormones, the hypothalamus releases thyroid-releasing hormone that stimulates the pituitary gland to secrete thyroid-stimulating hormone. The pituitary hormone is the one that activates the actual thyroid gland to release the thyroid hormones.

4) Which hormone is NOT released from the pituitary gland?

d. Insulin
Growth hormone, prolactin, luteinizing hormone, and follicle-stimulating hormone are all released from the pituitary gland. Insulin is released from the pancreas.
5) How do amino acid-derived hormones differ from peptide hormones?
Amino acid-derived hormones are chemicals that derive from a single amino acid, typically tyrosine or tryptophan. Peptide hormones are synthesized from proteins, or groups of several different amino acids.

6) The thyroid gland requires what atom for proper function?

c. Iodine
The thyroid hormones, T3 and T4, incorporate three or four iodine atoms, respectively, in its structure.

7) The primary function of the pineal gland is regulatingc. Circadian rhythm
A circadian rhythm is any biological process that occurs every 24 hours, like melatonin release from the pineal gland that depends on the absence of light.

8) Describe the relationship between the hypothalamus and the pituitary gland.

Both endocrine glands are located in the brain, but the hypothalamus primarily releases hormones that regulate the pituitary gland and its synthesis and secretion of different hormones.

9) Why is the receptor for the steroid hormones on the inside of the cell, while most peptide hormone receptors are located on the cell surface?
Steroid hormones are lipid soluble because they derive from cholesterol. Because of their lipid solubility, they are able to cross the cell membrane, and bind to intracellular receptors. Most peptide hormones are water soluble, and are unable to cross the cell membrane. For that reason, their hormones are located on the cell surface.

The Nervous System

1) Describe the two parts of the autonomic nervous system and what they control.

The autonomic nervous system is split into the sympathetic and parasympathetic systems. They send messages to the same organs but elicit antagonistic responses. The sympathetic system is responsible for the autonomic responses associated with fear and stress. It causes the heart to beat faster, decreases digestion, and ups blood pressure. The parasympathetic system is in control during relaxed situations, and it decreases heart rate and blood pressure, and activates digestion.

2) The brain sends its directions for motor movement to the _______ system.

b. Somatic
The autonomic and somatic systems fall within the larger peripheral nervous system. While the autonomic system controls unconscious processes like breathing, the somatic system controls the voluntary processes, like motor movement.

3) The ______ is the site of neurotransmission.

d. Synapse
The synapse is the physical location of neurotransmission. On one side of the synapse is the presynaptic axon where neurotransmitters are released. The other side of the synapse is the postsynaptic dendrite. While white matter is an area of the brain where neurotransmission occurs, it is not the site of neurotransmission.

4) Describe the transfer of information between the PNS and CNS as you see a snake and as you run away from the snake.
The PNS sends visual cues to the CNS through sensory neurons. After the CNS decides what to do with that information, it sends information through motor neurons in the somatic system to contract the skeletal muscles in your legs to flee the area. If you become scared at the sight of snakes, the CNS will also activate the sympathetic side of the autonomic system which will contract the heart muscles and constrict the pupils.

5) What is the difference between white and gray matter?White matter constitutes the inside of the brain, and primarily consists of myelinated axons that give the area its white color. Most neuronal communication occurs in the white matter. The gray matter lies on the outer parts of the brain, and is composed of cell bodies, dendrites, and unmyelinated axons.

6) What makes up a nerve?A nerve is a bundle of axons and dendrites.

7) What is the difference between an axon and a dendrite?Axons are long thin processes that carry information away from a particular neuron. Dendrites are densely branched protrusions from a cell body that receive information and carry it to the neuron.

8) Which is not a neurotransmitter?

a. Glutamate
b. Dopamine
c. Acetylcholine
d. GABA
e. All are neurotransmittersGlutamate, dopamine, acetylcholine, and GABA are all distinct types of neurotransmitters.

9) What is the primary function of the forebrain?
The forebrain receives all sensory information from the PNS and relays it to the areas of the brain that can use that information.

Fitting It All Together

1) What are two ways the brain can talk to the immune system?

Because the brain is linked to the immune organs (like the bone marrow and thalamus) through the autonomic system, it can send messages to these organs and regulate leukocyte activity. Another way the brain regulates the immune system is by activating a hormone cascade pathway within the endocrine system. Many hormones, including cortisol of the HPA axis, can act at the immune system.
2) True or False. Cytokines are chemicals that solely activate the immune system.False. With high enough concentrations, cytokines can diffuse into the blood. From there, they are able to activate the sensory nerves to send signals to the brain. They can also activate the brain directly and affect endocrine signaling by binding to the pituitary and adrenal glands.

3) What endocrine glands are involved in the HPA axis activity?

Hypothalamus, pituitary, and adrenal glands.
4) Too little of this hormone, or a resistance to it's activity, causes diabetes.c. InsulinIn diabetes, the body is unable to adequately respond to insulin. Diabetics are still able respond to glucagon by increasing blood sugar levels.

5) What is an autoimmune disease?
Autoimmune diseases arise when the immune system incorrectly attacks healthy cells.

6) Multiple sclerosis starts out as an autoimmune disease targeted at ______.
e. Myelin
Myelin coats the nerves of the nervous system, allowing for rapid neuronal communication. In multiple sclerosis, it is thought that the immune system incorrectly sees myelin as an invading pathogen, and attacks the nerve coating.

7) Why does Parkinson's disease affect movement?
Parkinson's disease is associated with a loss of dopamine in the basal ganglia. This is the brain area that's responsible for movement initiation and control. Without dopamine, the basal ganglia can't function correctly, and voluntary movement is compromised.

8) What is a common way to treat autoimmune diseases?Because these diseases are associated with too much immune activity, suppressing the entire immune system is a common treatment. Multiple sclerosis is sometimes treated with an anti-inflammatory drug to combat the active immune system.

9) Type II diabetes often occurs in overweight people, and is caused by insulin ______.a. resistance
Insulin resistance occurs in Type II diabetes. The hormone is still released, but the body does not properly respond by lowering blood sugar levels.

10) True or False. Type II diabetes is thought to result from an autoimmune disorder.
False. Type II diabetes is associated with excess weight and poor diet. An autoimmune disorder is thought to underlie some cases of Type I diabetes.