Anatomy and Physiology 2 - study questions (intro nervous system)

What are the three different jobs of a nervous system?

The nervous system has three primary functions: sensory input (collecting information from sensory receptors about the environment), integration (processing and interpreting the sensory input), and motor output (responding to the interpreted input by triggering effector organs like muscles or glands).

What's the difference between afferent and efferent neurons?

Afferent neurons, also known as sensory neurons, carry information from sensory receptors towards the central nervous system. Efferent neurons, also referred to as motor neurons, carry signals away from the central nervous system towards the effector organs.

What are the different types of receptors in the body, and what does each do?

There are many types of receptors in the body, including thermoreceptors (detect changes in temperature), photoreceptors (respond to light), nociceptors (respond to pain), chemoreceptors (detect chemicals in the environment or blood), and mechanoreceptors (respond to mechanical pressure or distortion).

What does the peripheral nervous system do, and what are the different divisions of the peripheral nervous system?

The peripheral nervous system connects the central nervous system to the rest of the body. It has two main divisions: the somatic nervous system (controls voluntary muscular functions) and the autonomic nervous system (controls involuntary functions like heartbeat and digestion).

What is a neuron, and what are the different parts of a neuron?

A neuron is a nerve cell that transmits information through electrical and chemical signals. It consists of the cell body, dendrites (branch-like structures that receive signals), and an axon (a long projection that transmits signals to other cells).

What does a schwann cell do?

Schwann cells produce the myelin sheath, a protective layer that insulates the axon and speeds up signal transmission.

What is the resting potential, and how is it established?

The resting potential is the electrical potential of a neuron when it's not actively transmitting signals. It's established by the difference in concentration of ions inside and outside the neuron, and maintained by the sodium-potassium pump.

What is the action potential, and how does it occur?

The action potential is a rapid, temporary change in the electrical potential across the membrane of a neuron, caused by the influx of positively charged sodium ions into the cell and the efflux of potassium ions.

How does one neuron communicate with another across the synapse?

Neurons communicate across synapses via neurotransmitters. The action potential triggers the release of neurotransmitters from the presynaptic neuron. These neurotransmitters bind to receptors on the postsynaptic neuron, generating a response.

What are graded potentials and where do they occur?

Graded potentials are changes in membrane potential that vary in size and occur in the dendrites and cell body of a neuron.

What are the different types of neurons, and where are they found in the body?

Types of neurons include sensory neurons (found in sensory organs and carry signals to the CNS), motor neurons (carry signals from the CNS to muscles and glands), and interneurons (found within the CNS and process information).

Why does an action potential travel down an axon?

An action potential travels down an axon to transmit a signal from the cell body of a neuron to its target.

What's the difference between stimulatory and inhibitory graded potentials?

Stimulatory graded potentials cause depolarization and increase the likelihood of an action potential, while inhibitory graded potentials cause hyperpolarization and decrease the likelihood of an action potential.

What's the difference between spatial and temporal summation?

Spatial summation is the summing of potentials from different parts of the cell. If the overall sum can depolarize the cell, an action potential will occur. Temporal summation is the summing of potentials that arrive at the axon hillock at different times. The closer together the times of arrival, the greater the likelihood of an action potential.