Question

1 which immune system disorder involves the immune system attacking the bodys own cells?
a. immunodeficiency
b. allergies
c. viral infection
d. autoimmune disease
2 what is the primary function of macrophages?
a. to engulf and digest pathogens
b. to produce antibodies
c. to store immune cells
d. to transport oxygen
3 which feedback mechanism is used to regulate body temperature?
a. negative feedback
b. hormonal feedback
c. positive feedback
d. both positive and negative feedback
4 what is the function of the spleen in the immune system?
a. to produce antibodies
b. to filter blood and initiate immune responses
c. to destroy cancerous cells
d. to store b cells
5 what does the peripheral nervous system (pns) do?
a. processes and stores information
b. controls involuntary body functions
c. transmits information between the cns and the rest of the body
d. commands reflex actions
6 what is the primary purpose of the immune system?
a. to produce hormones
b. to protect the body against pathogens
c. to digest food
d. to regulate blood pressure
7 which part of a neuron receives signals from other neurons?
a. myelin sheath
b. dendrites
c. axon
d. glia

Explanation:

1. Autoimmune diseases are defined by the immune system mistakenly attacking the body's own healthy cells.
2. Macrophages are phagocytic cells that engulf and break down pathogens.
3. Negative feedback reverses deviations from a set point, which is how body temperature is regulated (e.g., cooling down when overheated, warming up when too cold).
4. The spleen filters blood, removes old/abnormal blood cells, and initiates immune responses against pathogens in the blood.
5. The Peripheral Nervous System (PNS) acts as a communication network, carrying signals between the Central Nervous System (CNS) and the rest of the body.
6. The core purpose of the immune system is to defend the body against invading pathogens like bacteria, viruses, and fungi.
7. Dendrites are the branched extensions of a neuron that receive electrical signals from other neurons.

Answer:

1. d. Autoimmune disease
2. a. To engulf and digest pathogens
3. a. Negative feedback
4. b. To filter blood and initiate immune responses
5. c. Transmits information between the CNS and the rest of the body
6. b. To protect the body against pathogens
7. b. Dendrites