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Flashcards in Chapter 14 Deck (53)
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31

Classes of sympathetic receptors: Cholinergic receptors bind to ................. and include the following two types: ..................... and ....................

acetylcholine. muscarinic, and nicotinic receptors

32

Where are muscarinic receptors located? Where are nicotinic receptors located?

muscarinic: sweat glands in skin. nicotinic: adrenal medulla

33

Explain how alpha-2 receptors differ from the other adrenergic receptor subtypes.

found in preganglionic sympathetic neuron. They prevent action potentials from firing to postganglionic cells, and are part of the shut off system for sympathetic response.

34

Summarize the effects of norepinephrine on cardiac muscle cells when it binds b-1 receptors

increase in heart rate and force of contraction, which increases blood flow to tissues and increases blood pressure

35

Constriction of blood vessels serving the digestive, urinary, and integumentary system occurs when norepinephrine binds to ............... receptors, which decreases blood flow to these organs.

alpha 1

36

Dilation of the bronchioles occurs when norepinephrine binds to ................ receptors, which increases the amount of oxygen that can be inhaled with each breath.

beta 2

37

Dilation of blood vessels serving the skeletal and cardiac muscle occurs when norepinephrine binds to b-2 receptors, which .................... the blood flow, allowing for an increase in physical activity.

increases

38

Relaxation of the smooth muscle of the digestive tract occurs when norepinephrine binds to b-2, which .................... digestion during increased physical activity.

slows

39

Dilation of the pupils occurs when norepinephrine binds to a-1 receptors that cause the dilator papillae muscles to contract, which causes the pupil to allow ............... .

light in by dilating

40

Constriction of blood vessels serving most exocrine glands occurs when norepinephrine binds to beta receptors on the blood vessels serving various salivary glands, which ................. the secretion of saliva, with the exception of sweat glands.

decreases

41

Effects on cellular metabolism: during times of sympathetic nervous activation, nearly all cells, especially skeletal muscle, require higher amounts of ATP. To assist with this higher energy demand norepinephrine has the following three effects:

1. triggers the breakdown of fatty acids for fuel
2. binds to liver to trigger release of glucose
3. binds to pancreas to trigger release of glucogon

42

Effects on secretion from sweat glands: the sympathetic nervous system attempts to maintain body temperature homeostasis during periods of increased physical activity. Summarize the process:

postganglionic neurons release ACh that binds to muscarinic receptors and increases secretions of sweat

43

Effects on cells of the adrenal medulla: the adrenal medulla sits on top of each kidney. It is in direct contact with preganglionic sympathetic neurons. The medulla of this multifunctional endocrine gland is composed of modified sympathetic postganglionic neurons with the following functions:

1. ACh is released from preganglionic neurons that then bind to ............ receptors on the adrenal medulla cells.

2. ACh stimulates the medullary cells to release ............... and .................... into the bloodstream. In this case these are considered hormones rather than neurotransmitters.

3. These hormones act as long-distance chemical messengers and act as an interface between the endocrine and sympathetic nervous systems.

1. nicotinic
2. epinephrine and norepinephrine

44

What are some of the functions the parasympathetic nervous system maintains?

body's maintenance, digestion and urine formation

45

Parasympathetic cranial nerves are associated with the .......... (CN III), ................. (CN VII), ............. (CN IX), and ............... (CN X) nerve.

Oculomotor III, Facial VII, Glossopharyngeal IX, and Vagus X

46

The two ........... nerves are the main parasympathetic nerves that innervate most thoracic and abdominal viscera.

Vagus X

47

Branches of the vagus nerves contribute to the .............., and ............. plexuses.

cardiac, pulmonary, esophogeal

48

The parasympathetic sacral nerves make up the pelvic nerve-component of this division. This subdivision supplies the last segment of the large intestine, the urinary bladder, and the reproductive organs.
Sacral nerve branches form the pelvic ................ nerves, which form plexuses in the pelvic floor.

splachnic

49

Parasympathetic Neurotransmitters and Receptors: both pre and postganglionic parasympathetic neurons release ................. at their synapses, and the effect is generally ................... The following two cholinergic receptors are components of this ANS division:
1. ..................... receptors are located in the membranes of all postganglionic neurons.
2. .................... receptors are located in the membranes of all parasympathetic target cells.

ACh, excitatory.
1. nicotinic
2. muscarinic

50

Effects on cardiac muscle cells: parasympathetic activity ............... heart rate and blood pressure.

decreases

51

Preganglionic parasympathetic neurons travel to the heart with the vagus nerve (CN X). Postganglionic neurons ................ the heart rate, which reduces the blood pressure.

reduce

52

Effects on smooth muscle cells: postganglionic neurons innervate smooth muscle cells in many organs with the following effects:

1. Constriction of the pupil involves the ................... nerves, CN III, the ciliary ganglion, and the sphincter papillae muscle, which reduces the amount of light allowed into the eye.

2. Accommodation of the lens for near vision involves the ................. nerves, CN III, and the contraction of the ................ muscle, which changes the lens to a more rounded shaped.

3. Constriction of the bronchioles or bronchoconstriction involves the ............... nerves, CN X.

4. Contraction of the smooth muscle lining the digestive tract involves the ................... nerves, CN X, which produces rhythmic contractions called peristalsis that propels food through the digestive tract.

5. Relaxation of digestive and urinary sphincters involves the .................... nerves, CN X, and sacral nerves, which promotes .............. and ......................

6. Engorgement of the penis or clitoris occurs when stimulated by the sacral nerves in the male or female respectively.

7. Although the parasympathetic division only innervates specific blood vessels, many blood vessels dilate when the system is activated, due to a reduction in sympathetic activity.

1. Oculomotor III
2. Oculomotor III, cilliary
3. Vagus X
4. Vagus X
5. Vagus X, urination and defecation

53

Effects on glandular epithelial cells: the parasympathetic division has little effect on sweat glands but does increase secretion production from other glands:

1. CN VII stimulation stimulates tear production from ................ glands and mucus production from glands in the nasal mucosa.

2. CN VII and IX stimulation leads to increased production of ................. from the salivary glands.

3. CN X stimulates secretion of enzymes and other products from .................... tract cells.

1. lacrimal
2. saliva
3. digestive