Test 2 (Chapters 22, 23, 24 and 45) Flashcards
Does the autonomic nervous system regulate visceral activities?
No
Are all of its neurons motor?
No, it’s a mix of motor and somatic
What are the major functions of the ANS?
Regulate heartbeat, smooth muscle contraction, glandular secretions, and metabolism
What can happen when preganglionic fibers are inside the sympathetic fiber?
- Can synapse with sympathetic postganglionic neuron
- Can send ascending/descending branches through the sympathetic trunk to synapse with postganglionic neurons in other chain ganglia
- Pass through one or more chain ganglia without synapsing
Why do sympathetic responses have a widespread affect on the whole body?
It is the fight-or-flight division, which serves as an emergency system
Where are parasympathetic preganglionic neuron cell bodies located?
Nuclei in the brainstem or lateral gray columns of the sacral cord
What do parasympathetic preganglionic neuron cell bodies do?
They extend a considerable distance before synapsing with postganglionic neurons
What does tonically active mean?
Remaining stable, being aware, flowing.
What do adrenergic fibers release?
Norepinephrine and epinephrine
What do cholinergic fibers release?
Acetylcholine
In parasympathetic division, is the preganglionic chain long or short?
Long
In the sympathetic division, is the preganglionic chain long or short?
Short
In the sympathetic division, is the postganglionic chain long or short?
Long
In the parasympathetic division, is the postganglionic chain long or short?
Short
In parasympathetic, the postganglionic chain releases acetylcholine, which makes the chain _______ and binds to what receptors?
Cholinergic, muscarinic
In sympathetic, the postganglionic chain releases norepinephrine or epinephrine, which makes the chain _______ and binds to what receptors?
Adrenergic, Alpha or Beta
What does acetylcholine stimulate?
Digestive glad secretion
What do special senses consist of?
General (somatic) and Special
What happens in the presence of a continuous stimulus?
The frequency (rate) of impulses declines quickly in rapidly adapting receptors
What are somatic senses?
Also known as general senses which involve touch, pressure, pain and temperature
Mechanoreceptors
activated when “deformed” to generate receptor potential
Chemoreceptors
Activated by the amount or changing concentration of certain chemicals, such as taste and smell
Thermoreceptors
Activated by changes in temperature
Nocireceptors
Activated by intense stimuli that may damage tissue (pain)
Photoreceptors
Found only in the eye (light); they respond to light stimuli if the intensity is great enough to generate a receptor potential
Osmoreceptors
Concentrated in the hypothalamus and are activated by changes in the concentration of electrolytes in extracellular fluids, stimulates the thirst center
What is another name for free nerve endings?
Nociceptors - primary receptors for pain
Tactile (Meissner) Corpuscle
Large numbers in hairless skin areas, such as nipples, fingertips and lips
Lamellar (Pacini) Corpuscle
Found in deep dermis and joint capsules; adapt quickly, but sensations they evoke seldom last long
Proprioception
Ability to sense stimuli arising within the body regarding position, motion and equilibrium.
What type of receptors are olfactory cells?
Chemoreceptors
What are chemoreceptors stimulated by?
Chemicals dissolved in the saliva
What are the 5 taste sensations?
Sweet, sour, bitter, salty and umami
What are the 3 auditory ossicles of the middle ear?
Malleus (hammer)
Incus (anvil)
Stapes (stirrup)
What is the malleus attached to?
Inner surface of the tympanic membrane
What is the opening from the external acoustic meatus covered with?
Tympanic membrane
What opening does the stapes fit into?
Oval window
What other window is covered by a membrane?
Round window
What is another opening of the middle ear?
Opening into the auditory (eustachian) tube
What is the cochlea associated with?
Hearing
What is the bony labyrinth composed of?
Vestibule, cochlea, and semicircular canals
What is the sclera?
Tough, white fibrous tissue
What is the retina made up of?
An outer layer of figmented epithelium and an inner layer of nervous tissue
What is strabismus?
An abnormal convergence
What are the refracting media of the eye?
The cornea, aqueous humor, lens and vitrous body
What are the 3 types of cones that are present in the retina?
S cones, M cones, L cones
S Cones
Blue-sensitive (short wavelengths)
M Cones
Green-sensitive (medium wavelengths)
L Cones
Red-sensitive (long wavelengths)
What is the reproductive system’s purpose?
To ensure survival of the genes that characterize the human species
What are the essential organs of the male reproductive system?
Gonads, testes
What are the accessory organs?
Genital ducts, glands, supporting structures
What are the supporting structures?
Scrotum, penis, and pair of spermatic cords
What make up the accessory glands?
Pair of seminal vesicles, one prostate, and a pair of bulbourethral glands
What is the tunica albuginea?
It encases each testes and sends out septa that divide the testes into 200 lobules
How much lower is the left testes from the right?
1 cm
