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Flashcards in Test 3 Deck (148)
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1

What are the two cells of nervous tissue?

neurons and glia

2

Which cranial nerve controls the Lateral Ptyregoid?

V. Trigeminal Nerve

3

What is another name for a neuron's cell body?

Perikaryon

4

What is another name for chromatophilic substance?

Nissl bodies

5

Nissl substance

Membranous organelles located in neuronal cell bodies and dendrites. Rough endoplasmic reticulum making peptide chains. It is not found in either axons or the axon hillock

6

Lower Motor Neurons are located where?

Brainstem and Spinal Cord

7

Which neurotransmitter does lower motor neurons use to communicate with the muscles?

Acetylcholine

8

How many pairs of spinal nerves are their?

31 pairs

9

Myasthenia gravis

Autoimmune disease that decreases cholinergic receptors. Acetylcholine is inhibited to help with this disease.

10

Rigor Mortis

stiffening of the body after death, contraction of the muscles.

11

Oligodendrocytes

-Glia of CNS found in high density in white matter
-produces myelin

12

Central Canal

Ventricle that contains Cerebral Spinal Fluid in center of spinal cord

13

Sarcoplasmic reticulum

Stores and sequesters calcium ions in muscle cells; smooth endoplasmic reticulum

14

Peristalsis

Smooth muscle contraction of tubular internal organs; digestive tract

15

I-bands

-Region of sarcomere with only actin present
-they shorten when sarcomere contracts
-held by direct attachments to structures called Z lines

16

Nodes of Ranvier

Unmyelinated regions of axons

17

tropomyosin

Protein located in grooves of actin that blocks myosin attachment

18

myosin crossbridges

-They connect to actin and pull actin toward the center, which contracts the sarcomere
-Loaded with ATP

19

Sliding filament hypothesis

the contraction of sarcomeres; theory of muscle contraction

20

myosin

proteins(thick & dark) that, with actin, forms the filaments that interact to contract muscle fibers

21

actin

Protein in a muscle fiber that forms the thin filaments(light) that slide between filaments of the protein myosin, shortening the muscle fibers.

22

Sarcomeres

the striations form a repeating pater of units along the muscle fiber

23

A-bands

the second part of the striation pattern, which composes thick myosin filaments overlapping thin actin filaments

24

ATPases

-an enzyme found in myosin heads
-it catalyzes the breakdown ATP to ADP and a phosphate

25

Tropomyosin

-rod-shaped and occupy the longitudinal grooves of the actin helix
-Prevents myosin cross bridges from binding/attaching to actin

26

Troponin

-High affinity for calcium
-attached to actin

27

Basic process of muscle contraction

Calcium is attached to troponin causing it to change shape and push tropomyosin out of the actin helix. With the removal of tropomyosin the myosin cross bridges can now attach to the actin, which causes the sarcomere to contract

28

Muscle relaxation

cross bridges have to be loaded with ATP, which allows the cross bridges to disconnect from the actin.

29

Triads

Region where the actin and myosin filaments overlap

30

Neuromuscular junction

-axon terminal of lower motor neuron
-synaptic cleft
-motor end plate