Anatomy & Physiology Study Guide: Muscles and Nervous System

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Q1. Compare and contrast skeletal muscle vs. cardiac muscle.

Background

Topic: Muscle Tissue Types

This question tests your understanding of the structural and functional differences between skeletal and cardiac muscle tissues.

Key Terms:

Skeletal muscle: Voluntary, striated, multinucleated, attached to bones.
Cardiac muscle: Involuntary, striated, single nucleus, found in the heart, intercalated discs.

Step-by-Step Guidance

Identify the location and function of each muscle type (skeletal vs. cardiac).
Compare their control mechanisms (voluntary vs. involuntary).
Examine their cellular structure (number of nuclei, presence of striations, intercalated discs).
Consider their ability to regenerate and their fatigue resistance.

Try solving on your own before revealing the answer!

Final Answer:

Skeletal muscle is voluntary, striated, multinucleated, and attached to bones for movement. Cardiac muscle is involuntary, striated, has a single nucleus per cell, and is found only in the heart. Cardiac muscle cells are connected by intercalated discs, which allow for synchronized contraction. Skeletal muscle can regenerate more easily, while cardiac muscle is more resistant to fatigue but has limited regenerative capacity.

Q2. What is the function of muscles?

Background

Topic: Muscle Function

This question tests your understanding of the general roles muscles play in the body.

Key Terms:

Movement
Posture
Heat production
Stabilization

Step-by-Step Guidance

List the primary functions of muscles in the body.
Explain how muscles contribute to movement and posture.
Describe how muscle activity generates heat.

Try solving on your own before revealing the answer!

Final Answer:

Muscles are responsible for movement, maintaining posture, stabilizing joints, and generating heat through contraction. These functions are essential for daily activities and homeostasis.

Q3. What are the defining features of cardiac, smooth, and skeletal muscle?

Background

Topic: Muscle Tissue Types

This question tests your ability to distinguish between the three types of muscle tissue based on their structure and function.

Key Terms:

Cardiac muscle: Striated, involuntary, intercalated discs.
Smooth muscle: Non-striated, involuntary, spindle-shaped cells.
Skeletal muscle: Striated, voluntary, multinucleated.

Step-by-Step Guidance

Identify the location of each muscle type in the body.
Describe the cellular structure (striations, nuclei, cell shape).
Explain the control mechanism (voluntary vs. involuntary).

Try solving on your own before revealing the answer!

Final Answer:

Cardiac muscle is striated, involuntary, and found in the heart with intercalated discs. Smooth muscle is non-striated, involuntary, and found in walls of hollow organs. Skeletal muscle is striated, voluntary, and attached to bones, with multiple nuclei per cell.

Q4. What is distendability of muscles?

Background

Topic: Muscle Properties

This question tests your understanding of the physical properties of muscle tissue.

Key Terms:

Distendability: The ability of muscle to stretch or expand.
Elasticity: The ability to return to original shape.

Step-by-Step Guidance

Define distendability in the context of muscle tissue.
Compare distendability to other properties like elasticity and contractility.
Explain why distendability is important for muscle function.

Try solving on your own before revealing the answer!

Final Answer:

Distendability refers to the ability of muscle tissue to stretch or expand beyond its resting length. This property is important for accommodating changes in muscle length during movement and maintaining flexibility.

Q5. What is the Sarcolemma, Sarcomere, T-tubule, Sarcoplasmic Reticulum? (What are some functions associated with each?)

Background

Topic: Muscle Cell Anatomy

This question tests your knowledge of the structural components of muscle cells and their functions.

Key Terms:

Sarcolemma: Muscle cell membrane.
Sarcomere: Functional unit of muscle contraction.
T-tubule: Invagination of sarcolemma, conducts action potentials.
Sarcoplasmic Reticulum: Stores and releases calcium ions.

Step-by-Step Guidance

Define each structure (sarcolemma, sarcomere, T-tubule, sarcoplasmic reticulum).
Describe the function of each in muscle contraction.
Explain how these structures interact during muscle contraction.

Try solving on your own before revealing the answer!

Final Answer:

The sarcolemma is the muscle cell membrane, the sarcomere is the contractile unit, T-tubules transmit action potentials into the cell, and the sarcoplasmic reticulum stores and releases calcium ions needed for contraction.

Q6. What is a Triad?

Background

Topic: Muscle Cell Structure

This question tests your understanding of specialized structures in skeletal muscle cells.

Key Terms:

Triad: Structure formed by a T-tubule and two terminal cisternae of the sarcoplasmic reticulum.

Step-by-Step Guidance

Identify the components of a triad in skeletal muscle.
Explain the role of the triad in muscle contraction.
Describe how the triad facilitates communication between electrical and chemical signals.

Try solving on your own before revealing the answer!

Final Answer:

A triad consists of a T-tubule flanked by two terminal cisternae of the sarcoplasmic reticulum. It allows for rapid transmission of action potentials and efficient release of calcium for muscle contraction.

Q7. What is Actin? Myosin? Troponin? Tropomyosin?

Background

Topic: Muscle Proteins

This question tests your knowledge of the proteins involved in muscle contraction.

Key Terms:

Actin: Thin filament protein.
Myosin: Thick filament protein.
Troponin: Regulatory protein.
Tropomyosin: Regulatory protein.

Step-by-Step Guidance

Define each protein and its role in muscle contraction.
Explain how actin and myosin interact during contraction.
Describe the regulatory function of troponin and tropomyosin.

Try solving on your own before revealing the answer!

Final Answer:

Actin forms the thin filaments, myosin forms the thick filaments, troponin binds calcium and regulates contraction, and tropomyosin blocks binding sites on actin until troponin moves it.

Q8. What is the A band, M line, I band, Z line?

Background

Topic: Sarcomere Structure

This question tests your understanding of the structural organization of the sarcomere.

Key Terms:

A band: Region with thick filaments (myosin).
M line: Center of the sarcomere.
I band: Region with thin filaments (actin).
Z line: Boundary of the sarcomere.

Step-by-Step Guidance

Identify each band or line in the sarcomere.
Describe the composition of each region (thick vs. thin filaments).
Explain the functional significance of each structure.

Try solving on your own before revealing the answer!

Final Answer:

The A band contains thick filaments, the I band contains thin filaments, the M line is the center of the sarcomere, and the Z line marks the boundary between sarcomeres.

Q9. Be able to tell me from start to finish how a muscle contraction occurs. (You must start at the motor neuron)

Background

Topic: Muscle Contraction Process

This question tests your understanding of the sequence of events in muscle contraction, starting from neural stimulation.

Key Terms:

Motor neuron
Neuromuscular junction
Action potential
Calcium release
Cross-bridge formation

Step-by-Step Guidance

Describe how a motor neuron releases neurotransmitter at the neuromuscular junction.
Explain how the action potential travels along the sarcolemma and into T-tubules.
Discuss how calcium is released from the sarcoplasmic reticulum.
Outline how calcium enables cross-bridge formation between actin and myosin.
Summarize the steps leading to muscle contraction, stopping before relaxation.

Try solving on your own before revealing the answer!

Final Answer:

Muscle contraction begins when a motor neuron releases acetylcholine at the neuromuscular junction, triggering an action potential in the muscle cell. This action potential travels along the sarcolemma and T-tubules, causing the sarcoplasmic reticulum to release calcium. Calcium binds to troponin, moving tropomyosin and allowing myosin to bind to actin, resulting in contraction.

Q10. What results in depolarization?

Background

Topic: Membrane Potential

This question tests your understanding of the changes in membrane potential during neural or muscle activity.

Key Terms:

Depolarization: Reduction in membrane potential.
Sodium ions (Na+)

Step-by-Step Guidance

Define depolarization in terms of membrane potential.
Identify which ions move across the membrane during depolarization.
Explain how ion movement changes the charge inside the cell.

Try solving on your own before revealing the answer!

Final Answer:

Depolarization occurs when sodium ions (Na+) enter the cell, making the inside more positive and reducing the membrane potential.

Q11. What ions are associated with depolarization and repolarization?

Background

Topic: Action Potential

This question tests your knowledge of the ions involved in changes in membrane potential.

Key Terms:

Depolarization: Sodium ions (Na+)
Repolarization: Potassium ions (K+)

Step-by-Step Guidance

Identify the ions responsible for depolarization.
Identify the ions responsible for repolarization.
Explain how the movement of these ions affects membrane potential.

Try solving on your own before revealing the answer!

Final Answer:

Depolarization is caused by the influx of sodium ions (Na+), while repolarization is caused by the efflux of potassium ions (K+).

Q12. What role does calcium play in a muscle contraction?

Background

Topic: Muscle Contraction Regulation

This question tests your understanding of the regulatory role of calcium ions in muscle contraction.

Key Terms:

Calcium ions (Ca2+)
Troponin
Tropomyosin

Step-by-Step Guidance

Describe how calcium is released during muscle contraction.
Explain how calcium interacts with troponin.
Discuss how this interaction affects tropomyosin and actin-myosin binding.

Try solving on your own before revealing the answer!

Final Answer:

Calcium binds to troponin, causing tropomyosin to move and expose binding sites on actin, allowing myosin to bind and initiate contraction.

Q13. What is the function of the nervous system?

Background

Topic: Nervous System Function

This question tests your understanding of the primary roles of the nervous system in the body.

Key Terms:

Sensory input
Integration
Motor output

Step-by-Step Guidance

List the main functions of the nervous system.
Explain how the nervous system processes information.
Describe how the nervous system responds to stimuli.

Try solving on your own before revealing the answer!

Final Answer:

The nervous system detects sensory information, integrates and processes it, and initiates motor responses to maintain homeostasis and coordinate body functions.

Q14. What are the divisions of the nervous system?

Background

Topic: Nervous System Organization

This question tests your knowledge of the structural divisions of the nervous system.

Key Terms:

Central Nervous System (CNS)
Peripheral Nervous System (PNS)

Step-by-Step Guidance

Identify the two main divisions of the nervous system.
Describe the components of each division.
Explain the functions of CNS and PNS.

Try solving on your own before revealing the answer!

Final Answer:

The nervous system is divided into the central nervous system (CNS), which includes the brain and spinal cord, and the peripheral nervous system (PNS), which includes nerves and ganglia outside the CNS.

Q15. What is the visceral and somatic divisions of the nervous system?

Background

Topic: Nervous System Subdivisions

This question tests your understanding of the functional subdivisions of the nervous system.

Key Terms:

Somatic: Controls voluntary movements.
Visceral (Autonomic): Controls involuntary functions.

Step-by-Step Guidance

Define the somatic division and its function.
Define the visceral division and its function.
Compare the types of activities controlled by each division.

Try solving on your own before revealing the answer!

Final Answer:

The somatic division controls voluntary movements of skeletal muscles, while the visceral (autonomic) division regulates involuntary functions like heart rate and digestion.

Q16. What is a neuron? What are its components? What occurs at each component?

Background

Topic: Neuron Structure and Function

This question tests your knowledge of neuron anatomy and the function of each part.

Key Terms:

Neuron: Nerve cell
Dendrites
Cell body (soma)
Axon
Axon terminal

Step-by-Step Guidance

Define a neuron and its main components.
Describe the function of dendrites, soma, axon, and axon terminal.
Explain how information flows through a neuron.

Try solving on your own before revealing the answer!

Final Answer:

A neuron consists of dendrites (receive signals), a cell body (processes signals), an axon (transmits signals), and axon terminals (release neurotransmitters). Information flows from dendrites to soma to axon to terminals.

Q17. What establishes resting membrane potential?

Background

Topic: Membrane Potential

This question tests your understanding of the factors that create the resting membrane potential in neurons.

Key Terms:

Resting membrane potential
Sodium-potassium pump
Ion gradients

Step-by-Step Guidance

Define resting membrane potential.
Identify the role of the sodium-potassium pump.
Explain how ion gradients contribute to membrane potential.

Try solving on your own before revealing the answer!

Final Answer:

Resting membrane potential is established by the sodium-potassium pump, which maintains higher K+ inside and higher Na+ outside, creating a negative charge inside the cell.

Q18. What are the neuroglia cells of the CNS and PNS?

Background

Topic: Neuroglia

This question tests your knowledge of the supporting cells in the nervous system.

Key Terms:

CNS: Astrocytes, oligodendrocytes, microglia, ependymal cells
PNS: Schwann cells, satellite cells

Step-by-Step Guidance

List the types of neuroglia in the CNS and PNS.
Describe the function of each type.
Compare their roles in supporting neurons.

Try solving on your own before revealing the answer!

Final Answer:

CNS neuroglia include astrocytes, oligodendrocytes, microglia, and ependymal cells. PNS neuroglia include Schwann cells and satellite cells. Each supports neurons in different ways, such as insulation, protection, and nutrient supply.

Q19. What role does Myelin play in generating an action potential?

Background

Topic: Myelination and Action Potentials

This question tests your understanding of how myelin affects nerve signal transmission.

Key Terms:

Myelin sheath
Saltatory conduction
Nodes of Ranvier

Step-by-Step Guidance

Describe the structure of the myelin sheath.
Explain how myelin affects the speed of action potential transmission.
Discuss the concept of saltatory conduction.

Try solving on your own before revealing the answer!

Final Answer:

Myelin increases the speed of action potential transmission by allowing the signal to jump between nodes of Ranvier, a process called saltatory conduction.

Q20. What is an action potential?

Background

Topic: Action Potential

This question tests your understanding of the electrical signals used by neurons.

Key Terms:

Action potential: Rapid change in membrane potential.
Depolarization
Repolarization

Step-by-Step Guidance

Define action potential.
Describe the phases of an action potential (depolarization, repolarization).
Explain the importance of action potentials in neural communication.

Try solving on your own before revealing the answer!

Final Answer:

An action potential is a rapid, temporary change in membrane potential that allows neurons to transmit electrical signals along their axons.

Q21. What is a neurotransmitter?

Background

Topic: Neurotransmitters

This question tests your understanding of chemical signaling in the nervous system.

Key Terms:

Neurotransmitter: Chemical messenger
Synapse

Step-by-Step Guidance

Define neurotransmitter.
Explain where neurotransmitters are released.
Describe their role in transmitting signals between neurons.

Try solving on your own before revealing the answer!

Final Answer:

A neurotransmitter is a chemical messenger released at synapses to transmit signals from one neuron to another or to a target cell.

Q22. What stimulates the release of a neurotransmitter?

Background

Topic: Neurotransmitter Release

This question tests your understanding of the mechanisms that trigger neurotransmitter release.

Key Terms:

Action potential
Calcium ions (Ca2+)

Step-by-Step Guidance

Describe how an action potential reaches the axon terminal.
Explain the role of calcium ions in neurotransmitter release.
Discuss the process of vesicle fusion and neurotransmitter exocytosis.

Try solving on your own before revealing the answer!

Final Answer:

The arrival of an action potential at the axon terminal causes calcium ions to enter, triggering vesicle fusion and neurotransmitter release into the synaptic cleft.

Q23. Where do the neurotransmitters go once released?

Background

Topic: Synaptic Transmission

This question tests your understanding of the fate of neurotransmitters after release.

Key Terms:

Synaptic cleft
Postsynaptic receptor

Step-by-Step Guidance

Describe the path of neurotransmitters after release.
Explain how neurotransmitters bind to postsynaptic receptors.
Discuss the effect of neurotransmitter binding on the postsynaptic cell.

Try solving on your own before revealing the answer!

Final Answer:

Neurotransmitters cross the synaptic cleft and bind to receptors on the postsynaptic cell, triggering a response.

Q24. What can happen to excess neurotransmitters? What are their fates.

Background

Topic: Neurotransmitter Fate

This question tests your understanding of how neurotransmitters are removed or recycled after synaptic transmission.

Key Terms:

Reuptake
Enzymatic degradation
Diffusion

Step-by-Step Guidance

List the possible fates of excess neurotransmitters.
Explain the process of reuptake.
Describe enzymatic degradation and diffusion.

Try solving on your own before revealing the answer!

Final Answer:

Excess neurotransmitters can be reabsorbed by the presynaptic neuron (reuptake), broken down by enzymes, or diffuse away from the synaptic cleft.

Q25. What is an EPSP? IPSP?

Background

Topic: Synaptic Potentials

This question tests your understanding of excitatory and inhibitory postsynaptic potentials.

Key Terms:

EPSP: Excitatory postsynaptic potential
IPSP: Inhibitory postsynaptic potential

Step-by-Step Guidance

Define EPSP and IPSP.
Explain how each affects the postsynaptic membrane potential.
Discuss the role of EPSPs and IPSPs in neural signaling.

Try solving on your own before revealing the answer!

Final Answer:

EPSPs depolarize the postsynaptic membrane, making it more likely to fire an action potential. IPSPs hyperpolarize the membrane, making it less likely to fire.

Q26. Be able to identify some excitatory and inhibitory neurotransmitters.

Background

Topic: Neurotransmitter Types

This question tests your knowledge of neurotransmitters and their effects.

Key Terms:

Excitatory neurotransmitters: Glutamate, acetylcholine
Inhibitory neurotransmitters: GABA, glycine

Step-by-Step Guidance

List examples of excitatory neurotransmitters.
List examples of inhibitory neurotransmitters.
Explain how each type affects postsynaptic cells.

Try solving on your own before revealing the answer!

Final Answer:

Excitatory neurotransmitters include glutamate and acetylcholine; inhibitory neurotransmitters include GABA and glycine.

Q27. Explain what occurs during a muscle relaxation phase.

Background

Topic: Muscle Relaxation

This question tests your understanding of the events that lead to muscle relaxation after contraction.

Key Terms:

Calcium reuptake
ATP
Cross-bridge detachment

Step-by-Step Guidance

Describe how calcium is removed from the cytoplasm.
Explain the role of ATP in detaching myosin from actin.
Discuss how the muscle returns to its resting state.

Try solving on your own before revealing the answer!

Final Answer:

During relaxation, calcium is pumped back into the sarcoplasmic reticulum, ATP detaches myosin from actin, and the muscle returns to its resting length.

Q28. What are the different types of neurons?

Background

Topic: Neuron Classification

This question tests your knowledge of neuron types based on structure and function.

Key Terms:

Sensory neurons
Motor neurons
Interneurons

Step-by-Step Guidance

List the main types of neurons.
Describe the function of each type.
Explain how they interact in the nervous system.

Try solving on your own before revealing the answer!

Final Answer:

Sensory neurons carry information to the CNS, motor neurons carry commands from the CNS to muscles, and interneurons connect neurons within the CNS.