Lecture 4 Flashcards

Question

Describe smooth muscle

Answer 1

Short, small, spindle shaped Involuntary contraction Non-striated (smooth) - but still have thin and thick filaments that attach to dense bodies Single central nucleus Located in the walls of hollow internal structures (blood vessels, intestines, skin)

Answer 2

A major protein is actinin

Answer 3

Sensory: detection of internal and external stimuli and transfer to CNS Integrative: analysis and storing of information Motor: stimulation of effectors (e.g. muscle and glands) through PNS i.e. motor here means “effector”

Answer 4

Neurons Neuroglia

Answer 5

Have a cell body Have branched dendrites Have axons Longest cells in the body (up to 1m - spinal cord to toe) Functions;: Conscious and unconscious control For our purposes: Do not divide High metabolic rate (die rapidly without O2)

Answer 6

They receive/input nerve impulses (action potentials) into the cell body

Answer 7

Outer portion of neutron Carries the nerve impulse away from the neuron

Answer 8

Unipolar Bipolar Multipolar Anaxonic

Answer 9

Have 2 or more dendrites Single axon Most common neurons in CNS All motor neurons are multipolar Some of the longest (spinal chord to toe muscles)

Answer 10

1 dendritic process (can branch at tip but not at cell body) 1 axon Has cell body between axon and dendrite Rare and small Location: Special sense organs (sight, smell, hearing) relay information from receptor to neurons

Answer 11

The dendrites and axon are continuous Cell body off to one side Whole part from where dendrites converge (come together into 1) is called the axon Most sensory nerves are unipolar Very long (1m) like motor nerves CNS-toe tip.

Answer 12

Rare and function poorly understood Anatomy cannot distinguish dendrites from axons Found in brain and special sense organs

Answer 13

Smaller than neurons but more numerous Found in both CNS and PNS Make up ~50% the volume of the CNS (“glue”). Do not propagate action potentials, but can communicate. Can divide within the mature nervous system Functions: Physical structure of nervous tissue Repair framework of nervous tissue Undertake phagocytosis Nutrient supply to Neurons Regulate interstitial fluid in neural tissue.

Answer 14

Star-shaped; largest; most numerous of neuroglia. Syncytium network. Support (have microfilaments) and repair (scar). Communicate with neurons via 'gliotransmitters’ e.g. glutamate Maintain environment around neuron e.g. by regulating ions. Maintain blood-brain barrier via endothelium. Wrap around vessels and influence their permeability

Answer 15

Form insulating multilayered myelin sheath (protein lipid layer) around CNS axons. Can myelinate more than one neuron cell’s axon. Accelerate the action potential.

Answer 16

They are phagocytic (resident macrophages) - protection Can be inactive or active

Answer 17

Produce cerebrospinal fluid (CSF). Line the Cerebrospinal Fluid (CSF)-filled ventricles in the brain and the central canal of the spinal cord. These single layer of predominantly cuboidal cells have cilia (flow) and microvilli (sampling). Located in ventricles and in other locations where CSF found. CSF mechanical buffer; moves nutrients and waste

Answer 18

CNS neuroglia PNS neuroglia

Answer 19

Astrocytes Oligodendrocytes Microglia Ependymal cells

Answer 20

Schwann cells Satellite cells

Answer 21

"PNS version of CNS oligodendrocyte” Form insulating myelin sheath around axons or can just support and surround several non-myelinated axons. (Note: One Schwann cell per axon for myelination but more axons/cell if just support).

Answer 22

They surround neuron cell bodies. Support and fluid exchange (equiv. to astrocytes in CNS).

Answer 23

The branch like things that come out of axons

Answer 24

The things that come together to form a dendrite