BSC 2085 EXAM 3 Question and Answer Grade A+ 100% Correct Questions and Answers

BSC 2085 EXAM 3 Question and Answer
Grade A+ 100% Correct Questions and
Answers
• Nervous System -✓✓includes all neural tissue in the body

• Two kinds of cells of neural tissue -✓✓neurons and neuroglia

• Neurons -✓✓Cells that send and receive signals; basic functional units of the
nervous system

• Neuroglia (glial cells) -✓✓Cells that support and protect neurons

• Organs of the Nervous System -✓✓brain, spinal cord, sensory receptors, nerves

• Anatomical Divisions of the Nervous System -✓✓Central Nervous System
(CNS) and Peripheral Nervous System (PNS)

• Central Nervous System (CNS) -✓✓Consists of the spinal cord and brain;
contains neural tissue, connective tissues, and blood vessels

• CNS Functions to process and coordinate: -✓✓•Sensory data
•Motor commands
•Higher functions of brain

• Peripheral Nervous System (PNS) -✓✓Includes all neural tissue outside the CNS

• PNS functions to: -✓✓•Deliver sensory information to the CNS
•Carry motor commands from the CNS to peripheral tissues and systems

• Peripheral nerves -✓✓Bundles of axons with connective tissues and blood vessels

• Peripheral nerves function -✓✓Carry sensory information and motor commands
in PNS

• Cranial nerves -✓✓connect to brain

,• Spinal nerves -✓✓attach to spinal cord

• Tract -✓✓bundle of axons in the CNS

• Nerve -✓✓bundle of axons in the PNS

• Functional Divisions of the PNS -✓✓Afferent division and efferent division;
receptors and effectors

• Afferent division -✓✓(A)pproaches CNS; Carries sensory info from PNS sensory
receptors to CNS

• Efferent division -✓✓(E)xits CNS; Carries motor commands from CNS to PNS
muscles and glands

• Receptors of PNS -✓✓Detect changes or respond to stimuli (internal/external);
receptors can be found on neurons and specialized cells; complex sensory organs

• Effectors -✓✓Respond to efferent signals coming from CNS; cells and organs are
effectors

• Two components of efferent division -✓✓Somatic Nervous System (SNS) and
Autonomic Nervous System (ANS)

• Somatic nervous system (SNS) -✓✓Controls voluntary and involuntary (reflexes)
skeletal muscle contractions

• Autonomic nervous system (ANS) -✓✓Controls subconscious actions,
contractions of smooth muscle and cardiac muscle, and glandular secretions

• Two divisions of ANS -✓✓Sympathetic division and parasympathetic division

• Sympathetic division -✓✓Stimulating effect
(fight or flight response)

• Parasympathetic division -✓✓Relaxing effect

,• Structure of neurons -✓✓cell body (soma), dendrites, axon

• Dendrites -✓✓Short, branched; used to receive information

• Axon -✓✓Long, single; sends information away from the soma towards a target
cell

• Typical organelles/structures of cell body -✓✓•Large nucleus and nucleolus
•Perikaryon (cytoplasm)
•Mitochondria
•Rough endoplasmic reticulum and ribosomes (produce NTs)

• Neuron cytoskeleton -✓✓neurofilaments, neurotubules, neurofibrils

• Neurofilaments -✓✓similar to intermediate filaments

• Neurotubules -✓✓similar to microtubules

• Neurofibrils -✓✓bundles of neurofilaments that provide support for dendrites and
axon

• Nissl bodies -✓✓Dense areas of RER and ribosomes; gray matter

• Dendritic spines -✓✓fine processes on each branch of dendrites; 80-90% neuron
S.A.; receive info from other neurons

• Action potential -✓✓electrical signals

• Axon structure -✓✓Axoplasm, axolemma, axon hillock, collaterals, telodendria,
axon (synaptic) terminals

• Axoplasm -✓✓Cytoplasm of the axon; contains neurofibrils, neurotubules,
enzymes, organelles

• Axolemma -✓✓Specialized cell membrane of the axon; covers the axoplasm

, • Axon hillock -✓✓Thick section of cell body found prior to axon; attaches to
initial segment of axon to the soma

• Initial segment important... -✓✓to the formation of an action potential

• Collaterals -✓✓Branches of a single axon

• Telodendria -✓✓Fine extensions of distal axon

• Axon (synaptic) terminals -✓✓Tips of telodendria; aka synaptic boutons/synaptic
knobs; contains mitochondria, portions of ER, and vesicles containing NTs; release
NTs which signals the target cell

• Most neurons lack... -✓✓centrioles and cannot divide (undergo mitosis); except
neural stem cells in the nose (to regenerate olfactory sensory receptors) and in the
hippocampus of the brain (involved in storing memories)

• Synapse -✓✓Area where a neuron communicates with another cell; involves 2
cells (DONT make physical contact)

• Presynaptic cell -✓✓Neuron that sends message

• Postsynaptic cell -✓✓Target cell that receives message

• Synaptic cleft -✓✓small gap that separates the presynaptic membrane and the
postsynaptic membrane

• Neurotransmitters (NTs) -✓✓Chemical messengers released from the presynaptic
membrane (exocytosis); affect receptors of postsynaptic membrane; broken down
by enzymes (in synaptic cleft); reassembled at axon terminal (reabsorbed and
reused)

• Axoplasmic transport -✓✓Neurotubules (used as roadways) within the axon;
transport raw materials; between cell body and axon terminal; powered by
mitochondria, kinesin, and dynein

• Kinesin -✓✓transports materials from soma to axon terminal; anterograde flow