Biology 30 - Diploma Review - All Units Exam Questions And Answers Graded A+!!!

What does the nervous system do in regards to homeostasis? - ANS The nervous system regulates body structures and processes to maintain homeostasis despite fluctuations in the internal and external environment. What are the two divisions of the nervous system? - ANS Central nervous system (CNS) Peripheral nervous system (PNS) What does the two parts of the nervous system collectively control? - ANS Together, the central nervous system and the peripheral nervous system control sensory input, integration, and motor output. What parts of the body are in the central nervous system and what is their main function? - ANS Consists of the brain and the spinal cord, integrates and processes information sent by nerves. What is the peripheral nervous system divided into? - ANS The peripheral nervous system is further divided into the somatic system and the autonomic system. What is the somatic system, and what is it's function? - ANS (Voluntary). The somatic system consists of sensory receptors in the head and extremities, nerves that carry sensory information to the central nervous system, and nerves that carry instructions from the central nervous system to the skeletal muscles. Its neurons service the head, trunk, and limbs. It's sensory neurons carry information about the receptors in the skin, tendons, and skeletal muscles. Its motor neurons carry information in the skeletal muscles. What is the autonomic system, and what is it's function? - ANS (Involuntary). Controls glandular secretions and the functioning of smooth and cardiac muscles. (Breathing, heart rate, etc). What are the two different parts of the autonomic system? - ANS Sympathetic (stress - fight or flight) and parasympathetic (cool down - relief - rest and digest). What is the functions of the sympathetic and parasympathetic branches of the autonomic system? - ANS Divisions of the automatic system often work in opposition to each other to regulate the involuntary processes of the body. Involuntary processes, such as heartbeat and peristalsis, are those that do not require or involved conscious control. What are the two types of cells that make up the nervous system? - ANS Glial cells and neurons. What are glial cells? - ANS Glial cells outnumber neurons and they account for about half of the volume of the nervous system. Glial cells nourish the neurons, remove their wastes, and defend against infection and provide supporting framework for all the nervous-system tissue. What are neurons? - ANS Neurons are basic structural and functional units of the nervous system. They are specialized to respond to physical and chemical stimuli to conduct electrochemical signals, and to release chemicals that regulate various body processes. What are individual neurons organized into? - ANS Tissues called nerves. What is the function of a nerve? - ANS Nerves extend neurons throughout the peripheral nervous system. The transmission pathway of the nervous system consists of which three functions? - ANS Sensory input, integration, and motor output. What happens in the sensory input stage of the transmission pathway? - ANS Sensory neurons gather information from the sensory receptors (senses) and transmit these impulses to the central nervous system (brain and spinal cord). What happens in the integration stage of the transmission pathway? - ANS Main function is to INTERPRET. Interneurons are found entirely within the central nervous system. They act as a link between the sensory and motor neurons. They process and integrate incoming sensory information, and rely outgoing motor information. What happens in the motor output stage of the transmission pathway? - ANS Motor neurons transmit information from the central nervous system to the muscles, glands, and other organs (effectors). What are reflex arcs, and what is the function of the reflex arc? - ANS Reflex arcs are simple connections of neurons that explain reflexive behaviours. Involuntary responses to certain stimuli are called reflexes. Reflex arcs use very few neurons to transmit messages, therefore reflexes can be very rapid. The reflex arc moves directly to and from the brain or spinal cord, before the brain centres involved with voluntary control have time to process the sensory information. What are the 4 parts of a neuron? - ANS Dendrites, axon, cell body and branching ends. What are dendrites and what is their function? - ANS Are short, branching terminals that receive nerve impulses from other neurons or sensory receptors, and relay the impulse to the cell body. The dendrites are numerous and highly branched, which increases the surface area available to receive information. What is the cell body, and what is it's function? - ANS Contains the nucleus and is the site of the cell's metabolic reactions. The cell body also processes input from the dendrites. If the input received is large enough, the cell body relays it to the axon, where an impulse is initiated. Contains cytoplasm. What is the axon and what is it's function? - ANS Conducts nerve impulses away from the cell body to the target cells. What is the function of the cell body? - ANS Houses the organelles and is the bridge between the dendrites and the axon. What is the function of the terminal branches? - ANS End with axon bulbs (synaptic knobs or end plates) that contain vesicles that secrete neurotransmitters. What is the myelin sheath? - ANS The myelin sheath in the peripheral nervous system is composed of Schwann cells that form neurilemma. What are Schwann cells? - ANS A type of glial cell that forms the myelin sheath in the peripheral nervous system. What are the Nodes of Ranvier? - ANS Gaps between the myelin sheath that increases the speed of the impulse via salutatory conduction, packed with ion channels to boost signal. What is neurilemma? - ANS A delicate membrane of the peripheral nervous system neurons that promotes the regeneration of damaged axons. What is a synapse? - ANS Gap between pre-synaptic and post synaptic neurons. What is the difference between what myelinated neurons form and what unmyelinated neurons form in the nervous system? - ANS In the central nervous system, myelinated neurons form what is known as white matter, and unmyelinated neurons form the grey matter. Most neurons in the peripheral nervous system are _______________. - ANS myelinated. What are the two different groups branched under the peripheral nervous system? - ANS Sensory pathways and motor pathways. What are the different groups branched under the motor pathways? - ANS Somatic and autonomic nervous system. What is the somatic nervous system? - ANS Part of the peripheral nervous system. Under conscious control (voluntary). What is the autonomic nervous system? - ANS Automatic. Part of the peripheral nervous system. Not under conscious control (involuntary). What does voltage (mV) measure? - ANS The electrical potential difference between the inside and the outside of the axon. What is resting potential, what happens? - ANS When the axon isn't conducting a nerve impulse the inside of the axon is a negative charge of (-70mV) with potassium (K+) and the outside has a positive charge of (+40mV) with sodium (Na+). The reason that it is more negative inside of the axon as it is outside is because the K+ ions are free to move in and out where as Na+ ions cannot move freely. Also there are negatively large proteins which are inside of the axon contributing to the negative charge.