Flashcards in Exam 3 Part two Deck (115):
The external ear is composed of?
External auditory meatus (canal)
Tympanic membrane (ear drum)
The middle ear is composed of?
Middle ear cavity
Middle ear ossicles-Malleus, incus, stapes
Middle ear muscles-Tensor tympani, stapedius
Oval window (receives stapes
Round window (releases pressure)
The inner ear is composed of?
Bony capsule=osseus labyrinth
Tubular sac=membranous labyrinth
Fluid of the inner ear are
Vessel that carries blood away from the heart
Vessel that carries blood to the heart
Pumped to the right side of the heart
Carry deoxygenated blood from the heart to the lungs
Carry oxygenated blood from the lungs to the heart
Pumped by the left side of the heart
Carry oxygenated blood from the heart to the organ system
Carry deoxygenated blood from the organ systems to the heart
Supplies the pulmonary & systemic circuits
3 layers of the heart
Cavity and membranes of the heart
What are the 5 changes that take place after birth?
1) Ductus arteriosus- ligamentum arteriosum
2) Ductus venosus- ligamentum venosum
3) Foramen ovale- fossa ovalis
4) Umbilical areteries- umbilical ligaments
5) Umbilical vein- round ligament
Extrinsic eye muscles
Often called extraocular muscles, move the eyes. Termed extrinsic because they origninate w/in the orbit & insert onto the white outer surface of the eye (sclera). Six extrinsic eye muscles; the rectus muscles (medial, lateral, inferior, & superior) and the oblique muscles (inferior & superior)
The medial rectus attaches to the
Anteromedial surface of the eye and pulls the eye medially (adducts the eye). Innervated by the CN III (Oculomotor nerve)
Attaches to the anterolateral surface of the eye and pulls the eye laterally (abducts the eye). Innervated by CN VI (abducens)
The inferior rectus
Attaches to the anteroinferior part of the sclera. Pulls the eye inferiorly (as when you look down) & medially (as when you look at your nose). Innervated by CN III
The superior rectus
Located superiorly & attaches to the anterosuperior part of the sclera. Pulls the eye superiorly (when you look up) & medially (as when you look at your nose). Innervated by CN III (oculomotor nerve)
The oblique eye muscles originate from within the
Orbit & insert on the posterolateral part of the sclera of the eye
The inferior oblique
Elevates the eye & turns the eye laterally. Innervated by CN III (Oculomotor nerve)
The superior oblique
Depresses the eye and turns the eye laterally. Passes through a pulleylike loop, called the trochlea, in the anteromedial orbit. Attaches to the superior posterior part of the eye, so contracting this muscle pulls the posterior part of the eye superiorly (but depresses the anterior surface of the eye). Innervated by CN IV (Trochlear)
Also called retina or internal tunic.
General function of the retina
The retina is the photo receptive sensory layer of the back of the eye (that covers about 65 percent of its interior surface), where the optics of the eye focuses an image of what is in front of the eye. The optic nerve carries signals from the retina to the brain, which interprets them as visual images. The retina has two types of cells the rods and cones. The cones are responsible for color vision while the rods provide black and white and night vision
Very light sensitive (night vision￼￼￼￼); but supplies grainy images & they do not distinguish between colors (black & white)
supply us with color perception & sharper, clearer images; but requires adequate light levels to function; three kinds of cones
Interpretation of sight is where?
Occipital lobes of cerebrum
Holds the lens in place
Contraction of ciliary muscles =
Relaxation of ligaments
Secrete cerumen (ear wax) which slows the growth of bacteria and traps dirt
Role of the auditory canal
Equalize pressure to the middle ear
The inner ear has
Cochlea, vestibule and semi-circular canals
Mesenteries ( intestines)
Positive feedback loop
Accelerates the original process, either to ensure that the pathway continues to run or the speed up its activities. Only a few of these feedback loops occur in the human body
An example of a positive feedback loop is
The process of milk release from the mammory glands
What are endocrine glands?
Ductless organs that secrete their molecular products directly into the bloodstream. All endocrine cells are located w/in highly vascularized areas to ensure that their products enter the bloodstream immediately
Endocrine v. other glands?
Ductless, direct into blood stream, hormones
Pancreas, Insulin and Blood Sugar levels are an example of what kind of feedback loop?
Steroids are derived from what common
The anterior & posterior Pituitary produce
how many hormones each?
7&0...why zero? FLATMPGAO
What is the “control center”?
General Characteristics of the Endocrine System
1. endocrine glands secrete hormones.
A. secreted into the bloodstream
B. affects "target” cell.
Derived from cholesterol; secreted mostly by reproductive organs and adrenal cortex
GENERAL CHARACTERISTICS OF THE
2. Glands are effectors
3. endocrine glands
Amino acid derivatives & thus small; thyroid hormones & melatonin from the pineal gland are examples
Polypeptide & protein
String of amino acids too large to pass through cell membranes. Most hormones are “peptide hormones”
e.g.-ALL pituitary hormones
What are the 3 influences of the hypothalamus as a control center?
1) Hormones stimulate the anterior pituitary-FSH, LH, ACTH, TSH, MSH, PRL, GH
2) Posterior pituitary hormones are actually made by the hypothalamus-ADH (Antidiuretic hormone) & oxytocin Travel down the axons in the infundibulum to be released by the posterior pituitary
3) Hypothalamus stimulates the Adrenal Medulla (neural)
Master control center of the endocrine system, regulates most endocrine activity
Connects the pituitary gland to the hypothalamus. Extends from the base of the hypothalamus at the median eminence
Most of the pituitary gland is composed of this. Also called adenohypophysis. Part of the pituitary gland that both produces & secretes hormones. Partitioned into 3 areas; pars distal is, pars intermedia, pars tuberalis
The pituitary gland is controlled by the
Hypothalamus. Nervous and endocrine systems combined
(Neurohypophysis) is the neural part of the pituitary gland because it was derived from nervous tissue at the base of the diencephalon. Composed of a rounded lobe called the pars nervosa & the infundibular stalk (infundibulum).
The thyroid gland
Largest gland entirely devoted to endocrine activities. located inferior to the thyroid cartilage of the larynx & anterior to the trachea. Covered by connective tissue capsule. Exhibits a butterfly shape.
The parathyroid gland
Located on the posterior surface of the thyroid gland. Usually 4 small nodules.
Hypothalamus location, hormones, & basic function
* Increase Ca++ in blood
* Immune response
* Adrenalin (epinephrine)
* Noradrenalin (norepinephrine)
* Glucose balance
* Ovaries and Testes
* Sex Hormones
* Estrogen, Progesterone & Testosterone
Change stimulus into action potential
What are the separate origins of the anterior pituitary glands?
1) The pars distalis
2) Pars intermedia
3) Pars tuberalis
The pars distalis is
The large anterior portion of the anterior pituitary
The pars intermedia is
A thin scant region between the pars distalis & the posterior pituitary
The pars tuberalis is
A thin wrapping around the infundibular stalk
What are the separate origins of the posterior pituitary glands?
1) Pars nervosa
2) Infundibular stalk (infundibulum)
Pars nervosa is
Round lobe part of the posterior pituitary
The infundibular stalk is
An elongated funnel-shaped structure that connects the hypothalamus with the pituitary gland
Types of receptors (origin)
Skin receptors & special ￼￼￼senses that supply information about the ￼outside world; located near body surface
Monitors conditions inside the body (i.e., internal organs)
Monitors body position (joints & muscles)
Types of receptors (stimulus)
Triggered by physical distortion
Respond to changes in temperature-free nerve endings
Pressure within organs
Respond to the presence of specific molecules- sense of smell (olfactory) & taste (gustatory)
Respond to changes in visible light energy
(or pain receptors): respond to extremes in temperature, mechanical damage & chemicals; free nerve endings
Felt in another part of body
The most superficial sensory receptors of the skin.
Can be associated with hair follicles
root hair plexus
Free nerve endings
What is the difference between encapsulated and unencapsulated nerve endings?
Unencapsulated nerve endings are dendrites without a connective tissue wrapping. Encapsulated nerve endings are dendrites wrapped in glial cells or connective tissue.
Encapsulated endings are
Dendrites wrapped in glial cells or connective tissue
Located on the posterior surface of the thyroid gland. Two types of cells in the parathyroid gland; chief cells & oxyphill cells.
Adrenal cortex exhibits
A yellow color as a consequence of the stored lipids in its cells. Its cells synthesize more than 25 diff. steroid hormones (corticosteroids). Partitioned into 3 regions; zona glomerulosa,zona fasciculata, zona reticularis
The zona glomerulosa in the adrenal cortex is a
Thin, outer cortical layer composed of dense, spherical clusters of cells. Synthesize mineralocorticoids
The zona fasciculata is the
Middle layer & the largest region of the adrenal cortex. Composed of parallel cords of lipid-rich cells. Synthesizes glucocorticoids
The zona reticularis is the
Narrrow band of small, branching cells. Capable of secreting minor amounts of sex hormones called gonadocorticoids. Secrete androgens
The adrenal medulla is
Forms the inner core of each adrenal gland. Consists of clusters of spherical cells called chromaffin cells.
Thyroid stimulating hormone: source, target, effects
Source: Thyrotropic cells of pars distalis (pituitary gland)
Hormone target: Thyroid gland
Effect: Stimulates thyroid hormone synthesis & secretion
Prolactin: source, target, effect
Source: Mammotropic cells of pars distalis (pituitary gland)
Hormone target: Receptors on organs throughout the body, female: mammary glands, male: interstitial cells in testes
Effect: female: Stimulates milk production in mammary glands
Male: May play a role in the sensitivity of the interstitial cells to LH
Adrenocorticotropic hormone (ACTH): Source, target, effect
Source: Corticotropic cells of pars distalis (pituitary gland)
Hormone target: adrenal cortez
Effect: Stimulates production of corticosteroid hormones
Growth hormone: source, target, effect
Source: Somatotropic cells of pars distalis (pituitary gland)
Hormone target: almost every cell in the body
Effect: Stimulates increased growth & metabolism in target cells; stimulates syntheiss of somatomedin in the liver to stimulate growth at epiphyseal plate
Follicle stimulating hormone: source, target, effect
Source: Gonadotropic cells of pars distalis (pituitary gland)
Hormone target: ovaries, testes
Effect: Stimulates growth of ovarian follicles, sperm production
leutinizing hormone: source, target, effect
Source: Gonadotropic cells of pars distalis (pituitary gland)
Hormone target: Ovaries, testes
Effect: Stimulates ovulation, estrogen & progesteron synthesis in corpus luteum of ovary, stimulates androgen synthesis in testes
Melanocyte stimulating hormone: Source, target, effect
Source: Cells of par intermedia (pituitary gland)
Hormone target: Melanocytes
Effect: Stimulates synthesis of melanin & dispersion of melanin granules in epidermal cells
Hormone whose production tends to be cyclic. Increases at night & decreases during the day. Helps regulate a circadian rhythm (24 hour body clock)
Day-night cycles. Referred to as the "body clock", a 24-hour cycle that rules us all. This internal body clock is affected by external forces, such as sun rise and time zones. And when one's circadian rhythm is disrupted, sleeping and eating patterns can run amok
Thyroid hormone: source, target, effect
Source: Follicular cells of thyroid gland
Hormone target: Most body cells
Effect: Increases metabolism, O2 use, growth, & energy use; supports & increases rate of development
Calcitonin: source, target, effect
Source: Parafollicular cells of thyroid gland
Hormone target: Bone, kidney
Effect: Reduces calcium levels in body fluids; decreases bone resorption & increases calcium deposition in bone