Test1

1. Nervous System Functions

Sensory input, Integration, Motor output

2. Nervous System Role

Controls all bodily functions, from basic reflexes to complex thoughts and emotions

3. Sensory Input

Detecting stimuli from the environment

4. Integration

Processing sensory information and deciding on a response

5. Motor Output

Activating muscles or glands to produce a response

6. Central Nervous System (CNS)

Consists of the brain and spinal cord, acts as the main control center

7. Peripheral Nervous System (PNS)

All nerves branching off from the brain and spinal cord, facilitating communication between the CNS and the rest of the body

8. Sensory (Afferent) Division (PNS)

Carries sensory information to the CNS

9. Motor (Efferent) Division (PNS)

Carries commands from the CNS to muscles and glands

10. Somatic Nervous System

Voluntary subdivision of the motor (efferent) division

11. Autonomic Nervous System

Involuntary subdivision of the motor (efferent) division

12. Sympathetic Division (Autonomic)

Mobilizing division of the autonomic nervous system

13. Parasympathetic Division (Autonomic)

Relaxing division of the autonomic nervous system

14. Main Cells of Nervous Tissue

Neurons and Neuroglia (glial cells)

15. Neuroglia (Glial Cells)

More numerous than neurons; have various important functions (once thought just supportive)

16. Neuron Characteristics

Longevity, irreplaceability (mostly amitotic), high metabolic rate

17. Soma (Cell Body)

Central part of the neuron; contains the nucleus and other organelles

18. Dendrites

Branch-like extensions of the soma; receiving end of the neuron; receive signals from other neurons

19. Axon

Long, wiry process that extends from the soma; transmits signals away from the cell body

20. Axon Terminals

Branched endings of the axon; transmitting end of the neuron; release neurotransmitters

21. Neuron Structural Classification

Based on the number of processes extending from the cell body (multipolar, bipolar, unipolar)

22. Neuron Functional Classification

Based on the direction of impulse travel (sensory/afferent, motor/efferent, interneurons/association neurons)

23. Bones (Nervous System Protection)

Outermost layer; skull (cranium) for the brain and vertebrae for the spinal cord; protect against direct impact

24. Meninges

Second layer of defense; three tissue layers surrounding the brain and spinal cord; help prevent brain damage

25. Dura Mater

Outermost meningeal layer; durable dense connective tissue covering the CNS

26. Arachnoid Mater

Thin, delicate meningeal layer, separated from dura mater by the subdural space

27. Subarachnoid Space

Space between arachnoid and pia mater; contains blood vessels and tissue projections (trabeculae); circulates cerebrospinal fluid (CSF)

28. Pia Mater

Innermost meningeal layer; very thin tissue that adheres directly to the brain, going into its grooves

29. Leptomeninges

Collective term for the arachnoid and pia mater

30. Oligodendrocytes

CNS glial cells; insulate neurons with myelin sheath; myelinate multiple axons; provide trophic support

31. Schwann Cells

PNS glial cells; insulate neurons with myelin sheath; myelinate a small portion of one axon; provide trophic support

32. Microglia

CNS glial cells; specialized macrophages; brain's first immune responders; consume and break down harmful substances through phagocytosis

33. Ependymal Cells

CNS glial cells; epithelial cells; produce cerebrospinal fluid (CSF); line CSF-filled ventricles and central canal; cilia help circulate CSF

34. Satellite Cells

PNS glial cells; found in ganglia; thought to have functions similar to astrocytes (regulating microenvironment, responding to injury)

35. Tropic Molecules

Originate from Greek "tropos" ("to turn"); molecules (usually hormones) that turn toward a chemical stimulus to trigger production of a different hormone; released by anterior pituitary gland

36. Trophic Molecules

Originate from Greek "trophos" ("nourishment"); molecules that aid in the growth and development of other molecules/cells

37. Adrenocorticotropic Hormone (ACTH)

Example of a tropic hormone; stimulates adrenal glands to release glucocorticoids

38. Thyroid-Stimulating Hormone (TSH)

Example of a tropic hormone (thyrotropin); stimulates thyroid gland to release thyroid hormone

39. Neurotrophic Factors

Examples of trophic molecules; include nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF); involved in neurodegenerative diseases

40. Astrocytes Prevalence

Very common; outnumber neurons significantly in some brain regions

41. Astrocytes Location

Found throughout the central nervous system (CNS), but not the peripheral nervous system

42. Astrocytes (Protoplasmic vs. Fibrous)

Classified as protoplasmic in gray matter and fibrous in white matter

43. Astrocytes and Blood-Brain Barrier (BBB)

Provide structural support to endothelial cells, prevent leakage; act as vasomodulators, controlling blood flow

44. Astrocytes and Glutamate Excitotoxicity

Prevent it by converting glutamate into non-toxic glutamine

45. Astrocytes and Potassium Homeostasis

Regulate potassium ion homeostasis by removing excess potassium

46. Astrocytes as Energy Reservoir

Synthesize glycogen into lactate, providing an energy source for neurons

47. Astrocytes and Neuronal Development

Secrete factors essential for synaptogenesis (formation of synapses) and synapse maturation

48. Astrocytes as Stem Cells

Some adult astrocytes can act as stem cells for neurogenesis and gliogenesis

49. Glial Scar Formation

When brain is injured, astrocytes form a glial scar by synthesizing glial fibrillary acidic protein (GFAP)

50. Astrogliosis

Process where astrocytes form a glial scar, helping to fill the space of dying neurons and potentially contributing to neuronal regeneration

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Multiple-Choice Questions

1. Which of the following is NOT one of the three main functions of the nervous system?

A) Sensory input

2. The Central Nervous System (CNS) consists of:

A) All nerves branching off the brain and spinal cord

3. The Peripheral Nervous System (PNS) is primarily responsible for:

A) Processing information and deciding on a response

4. Which division of the Peripheral Nervous System carries commands from the CNS to muscles and glands?

A) Sensory (afferent) division

5. The autonomic nervous system is a subdivision of which larger division?

A) Sensory (afferent) division

6. Which division of the autonomic nervous system is responsible for mobilizing the body for action?

A) Somatic division

7. The two main types of cells densely packed in nervous tissue are:

A) Astrocytes and Microglia

8. Which characteristic is typical of neurons?

A) They are mostly replaceable (mitotic)

9. The part of a neuron that typically receives signals from other neurons is the:

A) Axon terminal

10. What is the primary function of the axon?

A) To receive signals

11. Neurons are classified structurally by:

A) The direction of impulse travel

12. The outermost layer of protection for the brain, consisting of the skull, is known as the:

A) Meninges

13. How many tissue layers comprise the meninges?

A) Two

14. Which meningeal layer is a thin, delicate layer separated from the dura mater by the subdural space?

A) Pia mater

15. The subarachnoid space contains:

A) Only blood vessels

16. The arachnoid mater and pia mater are sometimes collectively referred to as the:

A) Dura mater

17. Both oligodendrocytes and Schwann cells are responsible for:

A) Phagocytosis of harmful substances

18. Which glial cells are specialized macrophages in the CNS that act as the brain's first immune responders?

A) Astrocytes

19. Ependymal cells are epithelial cells that produce:

A) Myelin sheath

20. The Greek word "tropos," from which "tropic" originates, means:

A) Nourishment

21. Which type of molecule stimulates the production of a different hormone?

A) Trophic

22. Nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF) are examples of:

A) Tropic hormones

23. The soma of a neuron contains:

A) Only the axon

24. Which type of glial cell is found throughout the CNS but not the PNS?

A) Schwann cells

25. Astrocytes play a vital role in maintaining the blood-brain barrier by:

A) Myelinating neurons

26. How do astrocytes regulate potassium ion homeostasis?

A) By synthesizing glycogen into lactate

27. The process by which astrocytes form a glial scar after a brain injury is called:

A) Synaptogenesis

28. What protein do astrocytes synthesize when forming a glial scar?

A) Myelin Basic Protein

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Fill-in-the-Blank Questions

1. The nervous system's three main functions are sensory input, integration, and motor output.

2. The Peripheral Nervous System (PNS) facilitates communication between the CNS and the rest of the body.

3. The motor (efferent) division includes the somatic (voluntary) and autonomic (involuntary) nervous systems.

4. Neuroglia cells were once thought to be just supportive but are now known to have various important functions and are more numerous than neurons.

5. Neurons are mostly amitotic, meaning they are irreplaceable.

6. The basic structure of a neuron includes the soma, dendrites, and an axon.

7. Neurons are classified functionally based on the direction of impulse travel.

8. The skull (cranium) protects the brain, while the vertebrae protect the spinal cord.

9. The meninges are comprised of three tissue layers surrounding the brain and spinal cord.

10. The outermost meningeal layer, the dura mater, is a durable dense connective tissue.

11. The subarachnoid space, located between the arachnoid and pia mater, contains blood vessels and tissue projections.

12. The innermost meningeal layer is the pia mater, which adheres directly to the brain.