Flashcards in A & P Exam 4 Deck (343):
The endocrine system works with the ____ system to maintain homeostasis.
How does the endocrine system communicate with the rest of the body?
Hormones travel through bloodstream & act of specific target cells
Reaction to stimuli is ____ and duration of effects is ____ compared to the nervous system.
Chemical messengers produced by endocrine glands and secreted directly into blood vessels.
A cell that has receptors for a particular hormone is referred to as the ___ of that hormone.
Hormone secretion is usually controlled by what?
negative feedback system
Some endocrine glands, such as ____ ____ and _____ ____ are under direct stimulation from the nervous system.
Secretion of ____ and _____ from the adrenal medulla is stimulated by sympathetic nervous system.
epinephrine & norepinephrine
Are these major or minor endocrine organs? Pituitary gland, thyroid, parathyroid, adrenal gland, pancreas (islets), gonads.
Are these major or minor endocrine organs? Kidneys, stomach, small intestine, placenta, thymus, pineal body.
This endocrine gland is part of the diencephalon section of the brain. Its functions include appetite control, body temp regulation, control of wake-sleep cycles, controls activities of pituitary gland. Portal system of blood vessel links this with the anterior pituitary gland.
What structure in the hypothalamus secrete releasing and inhibitory hormones into portal blood vessels?
Including secreting releasing & inhibitory hormones, what else does the hypothalamus secrete? (2)
Antidiuretic hormone (ADH)
ADH & Oxytocin are transported to the ____ ____ for storage. They are released into the bloodstream by nerve impulses from the hypothalamus.
The pituitary gland is also known as the ____, which means to grow beneath.
This part of the pituitary gland is the most rostral portion. It is stimulated by hypothalamus and direct feedback from target organs and tissues to produce its hormones.
The anterior pituitary is also known as the
This is the caudal portion of the pituitary gland. It does not produce any hormones; stores and releases hormones produced by the hypothalamus.
The posterior pituitary is also known as the
Growth hormone is released from ____ gland. It is also known as somatotropin and somatotropic hormone.
Secretion of growth hormone by the pituitary is controlled by the ______ and ______ (somatostatin) from the hypothalamus.
growth hormone releasing hormone
growth hormone inhibitory hormone
____ is the only pituitary hormone that does not function through a target gland but instead exerts its effects on almost all tissues of the body.
GH (growth hormone)
This hormone: promotes growth in young animals, helps regulate metabolism of proteins, carbs, and lipids, increases protein synthesis in all cells of body, increases mobilization of lipids from storage in fat tissue and their breakdown for energy, decreases rate of glucose utilization.
GH decreases rate of glucose utilization, also called
In short, ___ enhances body protein, uses up fat stores, conserves carbs.
Growth Hormone deficiency; congenital deficiency usually due to destruction of somatotrophs by a cyst; primarily seen in German Shepherds; lack of growth
Excess secretion of GH prior to closure of physis
Excessive secretion of GH after closure of physis; most commonly a fuctional adenoma of the somatotropic cells in the pituitary; older male cats; increase in body size, diabetes due to anti-insulin effects of GH.
Secreted by AP, helps trigger and maintain lactation. Production & release continues as long as the teat or nipple continues to be stimulated by nursing or milking.
Secretion of prolactin from the AP is normally inhibited by what hormone from the hypothalamus?
Prolactin inhibitory hormone
When the lactating teat is stimulated, the hypothalamus secretes what hormone which stimulates the AP to release prolactin?
Thyroid Stimulating Hormone (TSH) is also known as
This hormone secreted by the AP stimulates growth & development of thyroid gland & causes it to produce its hormones.
Secretion of TSH is regulated by feedback from the thyroid gland. It has direct effects on AP gland & through changes in _______ hormone produced by the hypothalamus.
This hormone secreted by the AP stimulates growth & development of the adrenal cortex & release of some of its hormones.
Adrenocorticotropic Hormone (ACTH)
ACTH is regulated by feedback from the hormones of the adrenal gland to the (2)
hypothalamus & AP
ACTH can also be released quickly as a result of stimulation of the hypothalamus by
To override the inhibitory feedback system, the hypothalamus sends a burst of _____ hormone to the AP causing ACTH to be released quickly.
This hormone is secreted by the AP. In females, it stimulates oogenesis and stimulates cells lining the follicles to produce and secrete estrogens. In males, it stimulates spermatogenesis.
Follicle-Stimulating Hormone (FSH)
This hormone secreted by the AP completes process of follicle development in ovary, increasing amounts of estrogens feedback to AP & cause reduced production of FSH and increased production of ___.
Luteinizing hormone (LH)
LH levels reach a peak when follicle is fully mature which usually causes
After ovulation, LH stimulates cells in the empty follicle to multiply and develop into the
The corpus luteum produces ___ hormones necessary for the maintenance of pregnancy.
In the male, LH stimulates ____ ___ within the testes to development and produce testosterone.
This hormone secreted by the AP is associated with control of color changes in the pigment cells of reptiles, fish, and amphibians.
Melanocyte-Stimulating Hormone (MSH)
Administration of artificially large amounts of ___ to higher mammals can cause darkening of the skin from melanocyte stimulation.
The posterior pituitary gland, also known as ____, develops from the embryo's nervous system & looks like nervous tissue under the microscope.
The PP stores what 2 hormones produced in the hypothalamus?
antidiuretic (ADH) and oxytocin
The PP periodically releases ADH & oxytocin into the bloodstream in response to ___ impulses from the hypothalamus.
This hormone secreted from the PP has it effects on the uterus, causing contraction of the myometrium at the time of breeding & at parturition; causes milk letdown.
ADH helps prevent ____, loss of large quantities of water in the urine
Receptors in the ____ detect changes in osmotic pressure of blood that result from dehydration/hemoconcentration.
ADH travels to the ____ and causes resorption of more water from urine and returns it to the bloodstream. It also causes vasoconstriction.
ADH deficiency; pituitary (lack of ADH) or nephrogenic (no response to ADH); PU/PD, inability to concentrate urine; modified water deprivation test; dDAVP (derivative of ADH), continuous access to water.
(insipid means tasteless)
What stimulates the thyroid gland to secrete thyroid hormone?
This gland consists of 2 lobes on either side of the larynx.
Thyroid hormone is produced in the ____ of the thyroid gland.
Each thyroid follicle consists of simple, cuboidal glandular cells surrounding a globule of thyroid hormone precursor called
What are the 2 thyroid hormones?
Thyroid hormones have negative feedback on what 2 endocrine glands?
hypothalamus and pituitary
Which thyroid hormone is produced in greater abundance but converts to the other before producing effects on target cells.
These are effects of what hormones: influences development & maturation of CNS; growth & development of muscles and bones; calorigenic effect - regulates the metabolic rate of all body cells; allows animal to generate heat & maintain constant internal body temp.
Production of thyroid hormones increase with exposure to ____ and then increases metabolic rate to generate more heat.
TH affects metabolism of proteins, carbs, and lipids much like ___ does. Encourages synthesis of proteins if adequate energy sources, encourages breakdown of lipids for energy, discourages using carbs as energy source.
Deficiency of thyroid hormone
Hypothyroidism is most commonly what type? Lymphocytic thyroiditis and idiopathic atrophy of the thyroid gland.
CSX of what? Lethargy, weight gain, cold intolerance, alopecia.
DX of what disease? Free T4 by ED, T4, TSH, Csx
TX of hypothyroidism
thyroid hormone supplementation
Excessive thyroid hormone
Etiology of hyperthyroidism: ___ or ____ of thyroid gland typically in middle aged to older cats.
hyperplasia or neoplasia
CSX of what disease? PU/PD, polyphagia, weight loss, v/d, tachycardia, hyperactive
DX of what disease: T4, free T4, Csx
TX for hyperthyroidism
antithyroid drugs, sx, radioactive iodine
What disease? lack of iodine>decrease T4>increase TSH> hyperplasia of thyroid gland
Besides T3 & T4, the thyroid gland also secretes
Calcitonin is produced by ____ (____) cells located between thyroid follicles.
C cells (parafollicular cells)
This thyroid gland secretion helps maintain blood calcium levels, prevents hypercalcemia by encouraging excess calcium to be deposited in the bones.
___ is involved in muscle contraction, blood clotting, milk secretion, and formation & maintenance of the skeleton
Small, paled nodules in, on, or near the thyroid glands.
What hormone do the parathyroid glands produce?
parathyroid hormone (PTH) or parathormone
This hormone helps maintain blood calcium levels and prevent hypocalcemia.
PTH prevents ___ by converting Vit D into its active form calcitriol, causes kidneys to reabsorb calcium, releases calcium from bones.
What is the active form of Vit D?
This causes intestines to absorb calcium from food and releases calcium from bones.
____ __ is carried in the bloodstream to the liver, where it is converted into the prohormone calcidiol.
Circulating calcidiol can be converted into ____, the biologically active form of vit D, either in the kidneys or by monocyte-macrophages in the immune system.
A decreased production of PTH by the parathyroid gland.
Primary hypoparathyroidism is ___ in dogs and cats.
CSX of primary hypoparathyroidism are consistent with _____; weakness, seizures.
DX of primary hypoparathyroidism
measure serum PTH & ionized calcium
TX for primary hypoparathyroidism
calcitriol & calcium supplements
Neoplasia of the parathyroid gland; causes hypercalcemia.
With progressive renal disease, renal synthesis of calcitriol is also reduced. This causes
renal secondary hyperparathyroidism
Commonly seen in reptile not getting enough calcium or Vit D>increases PTH> mobilized calcium from bones> rubber jaw
Nutritional secondary hyperparathyroidism (NSHP)
The adrenal glands consist of what 2 glands?
Which organ are the adrenal glands located near?
What are the 3 layers of the adrenal cortex?
The adrenal cortex is under direction of which AP hormone?
What type of hormones are produced by the adrenal cortex?
What are the 3 main groups of steroid hormones released from the adrenal cortex?
Glucocorticoids, Mineralocorticoids, Sex hormones
What are the different types of glucocorticoids? (3)
cortisone, cortisol, corticosterone
These hormones produced by the adrenal cortex are under the direction of ACTH; have a hyperglycemic effect; also help maintain blood pressure & help the body resist the effects of stress.
Glucocorticoids are secreted by which 2 layers of the adrenal cortex?
zona fasiculata & zona reticularis
Sex hormones are secreted by which 2 layers of the adrenal cortex?
zona fasiculata & zona reticularis
The adrenal cortex produces androgens and estrogens, which are __ hormones, in small amounts.
Mineralocorticoids (e.g., aldosterone) are secreted by which layer of the adrenal cortex?
ACTH has only a mild impact on regulating secretion of this adrenal cortex hormone.
This adrenal cortex hormone regulates levels of important electrolytes (NA & K) in the body by: telling the kidneys to reabsorb NA & H2O follows; telling the kidneys to eliminate K.
Secretions of this adrenal cortex hormone are regulated by electrolyte concentrations, blood volume, arterial pressure, renal function, etc.
This part of the adrenal gland develops from nervous tissue & resembles nervous tissue microscopically. It produces epinephrine & norepinephrine.
What is the adrenal medulla controlled by?
sympathetic autonomic nervous system
Excessive production of cortisol
Hyperadrenocorticism in dogs
What disease: usually pituitary tumor, adrenal tumor, iatrogenic
CSX: PU/PD, polyphagia, panting, pot-belly, alopecia
DX: measure cortisol levels with ACTH stim test or low-dose dexamethasone suppression test
TX: trilostane - acts on adrenal cortex to block synthesis of steriods.
hyperadrenocorticism or Cushings
Hypoadrenocorticism is also called
What type of hypoadrenocorticism: idiopathic atrophy of all layers of adrenal cortex resulting in deficiency of both mineralocorticoids and gludocorticoids.
Primary adrenocortical insufficiency
What type of hypoadrenocorticism: reduced secretion of ACTH resulting in deficiency of glucocorticoids only
Secondary adrenocortical insufficiency
CSX: lethargy, anorexia, vomiting
DX: electrolytes, ACTH stim test
TX: mineralocorticoid supplement +/- glucoorticoid supplement
Hyperadrenocorticism in ferrets is do to an
excessive production of sex hormones
What disease: hyperplasia or neoplasia of adrenal cortex linked to early spay/neuter
CSX: alopecia, swollen vulva in females, prostatic cysts in males
DX: adrenal panel to evaluate levels of sex hormones
TX: adrenalectomy, Lupron, melatonin, deslorelin
hyperadrenocorticism in ferrets
This organ is located near the duodenum and has both exocrine and endocrine functions.
Groups of cells scattered throughout the pancreas with endocrine functions.
Islets of Langerhans (Pancreatic Islets)
Alpha cells produce
Beta cells produce
Delta cells produce
This hormone is regulated mainly by blood glucose concentration. It raises blood glucose levels by stimulating liver cells to convert glycogen to glucose and by stimulating gluconeogenesis.
This hormone is regulated by blood glucose concentration. It lowers blood glucose levels by causing glucose, amino acids, and fatty acids to be absorbed into the body cells.
This hormone secreted by the pancreas is the same as growth hormone inhibitory hormone. It is secreted when food is ingested. It inhibits secretion of insulin, glucagon, & GH; diminishes activity of the GI tract.
This pancreatic hormone prevents rapid exhaustion of food, making it available over a longer period of time.
Loss of beta cell function resulting in hypoinsulinemia. CSX: PU/PD, polyphagia, wgt loss. DX: CSX along w/persistent, fasting hyperglycemia & glucosuria. TX: insulin injections
Neoplasia of beta cells that causes increased insulin production. CSX: weakness, seizures from hypoglycemia. DX: hypoglycemia, hyperinsulinemia. TX: SX, corticosteriods.
What organ produces erythropoietin?
This hormone stimulates bone marrow to increase production of RBCs.
Production of erythropoietin is stimulated by
As RBC production increases, more O2 feeds back to kidneys and slows production of
Kidney failure results in ____ because of kidneys' inability to produce erythropoietin.
The kidneys release ___ in response to decreased blood volume/blood pressure.
Renin causes _____ to be converted to angiotensin I.
Angiotensinogen is produced by the
Renin causes angiotensinogen to be converted to
Angiotensin I is converted to angiotensin II by
angiotensin converting enzyme (ACE)
What causes the adrenal cortex to release aldosterone which causes the reabsorption of sodium from the kidneys.
Angiotensin II causes the adrenal cortex to release ___ which causes the reabsorption of sodium from the kidneys.
_____ causes the reabsorption of sodium from the kidneys, water follows sodium, therefore increasinng blood pressure.
Angiotensin II also tells the posterior pituitary to release ___ thereby conserving water and increasing blood pressure.
____ is produced by G cells in the wall of the pyloric antrum.
Secretion of gastrin is stimulated by presence of ___ in the stomach.
Gastrin encourages muscular ___ of the stomach wall.
What 2 hormones are secreted by cells lining the small intestine?
Secretin and cholecystokinin
Secretion of ___ occurs in response to presence of acid in the duodenum.
Secretin stimulates the pancreas to secrete ___ to neutralize the acid. It also inhibits peristalsis of the stomach.
______ stimulates the pancreas to release digestive enzymes into the duodenum in response to fats and proteins. It also inhibits peristalsis of the stomach.
The placenta produces what 2 hormones to help support and maintain pregnancy?
estrogen & progesterone
The placentas of humans and horses release what hormone that makes fat stored in the mother's body available for use.
_____ extends cranially from the level of the heart up into the neck region along both sides of the trachea. It is large in young animals & atrophies later in life.
___ plays an important part in the animal's developing immune system.
The thymus secretes ____, a hormone that stimulates the development of T-lymphocytes.
The pineal body secretes ___, a hormonlike substance that seems to affect moods and wake-sleep cycles. It may also play a role in the timing of seasonal estrous cycles in some species.
These are hormonelike substances derived from unsaturated fatty acids and produced in a variety of body tissues (skin, intestine, brain, kidney, lungs, repro organs, eyes)
What prostaglandin causes rupture of the corpus luteum? Also called lutalyse.
_____ influence blood pressure, blood clotting, inflammation, GI, respiratory, reproductive & kidney function.
The primary androgen is
Testosterone has an overall ___ effect in that it stimulates buildup of proteins in muscle and bone.
Ovaries are CONTROLLED by what 2 hormones?
FSH & LH
Ovaries PRODUCE what 2 hormones?
estrogens and progestins
Amount of estrogen produced by follicles ___ as follicles grow.
Increasing estrogen levels cause the AP gland to ___ the production of FSH and ___ the production of LH.
_____ occurs when LH level peaks or LH surge.
In induced ovulators, ___ causes the release of LH from the AP.
Corpus luteum produces several hormones collectively called
What is the principle progestin that helps prepare the uterus to receive the fertilized ovum and is needed to maintain pregnancy.
The ___ system is the single most important route of waste-product removal in the body.
____ removes nearly all the soluble waste products from the blood and transports them out of the body. Urea, salts, & other products
The urinary system is also a major route of elimination for excess water in the body. Normally, urine is about ___% water.
What other ways are waste products eliminated?
Resp. system: CO2
Sweat glands: water & salts
What is the study of the kidney?
The following are ways kidneys maintain ____:
removal of waste products; fluid balance regulation; acid-base balance regulation; production of hormones; influence release of ADH from PP; influence release of aldosterone from cortex of adrenal gland.
Where are the kidneys in relation to the abdominal cavity?
In most domestic animals (except pig) the right kidney is more ___ than the left.
cranial (righty tighty)
The kidneys are somehwat mobile and are pushed caudally as the diaphragm contracts. The left kidney is more ___ than the right.
mobile (lefty loosey)
The outer fibrous connective tissue layer of the kidney
The indented area on the medial side of the kidney. Ureter, nerves, blood & lymph vessel enter & leave kidney.
What species has an outwardly lobulated kidney?
Most kidneys are bean shaped except the right kidney of the horse is ___ shaped
Medulla of the kidney has numerous pyramid-shaped areas giving the medulla a scalloped appearance.
multipyramidal (multilobular) kidneys
___ is a cuplike extension of the renal pelvis into which the medullary pyramids fit. In cattle this empties directly into the ureter.
Which species has a smooth outer kidney but is multipyramidal?
Medullary pyramids fuse to occupy the entire inner area of the kidneys. Ex: dogs, horses, cats, sheep.
Unipyramidal (unilobular) kidneys
The basic functional unit of the kidney
The ___ is composed of a glomerulus surrounded by Bowman's capsule.
A "tuft" of capillaries within the renal corpuscle.
A double-walled capsule that surrounds in the glomerulus.
The space between the glomerulus and Bowman's capsule is the
The renal corpuscle filters ___ in the first stage of urine production.
Fluid filtered out of blood in the renal corpuscle is called
The renal corpuscle is located in the renal
What is the continuation of the capsular space of Bowman's capsule called?
Proximal Convoluted Tubule (PCT)
This is the longest part of the tubular system of the nephron. It has a twisting path through the cortex.
Epithelial cells lining the PCT are ___ and have a brush border that increases surface area for reabsorption and secretion functions.
When glomerular filtrate enters the PCT, it is now called
The Loop of Henle continues from the PCT. The descending loop of henle descends into the ___ and makes a U-turn.
Epithelial cells in the descending Loop of Henle still have a
Epithelial cells in the ascending Loop of Henle become ___ ____ and lose their ___ ____.
The distal convoluted tubule (DCT) is a continuation of the ascending
loop of Henle
DCT from all nephrons in the kidney empty into
This structure in the kidneys: carries tubular filtrate through the medulla to the renal pelvis; primary site of action of ADH; regulation of potassium & acid-base balance.
Collecting ducts are the primary site of action of what hormone?
ADH - antidiuretic hormone
Up to __% of the blood pumped by the heart goes to the kidneys.
Every __-__ min, all the circulating blood in the body passes through the kidneys.
Arterioles called ____ ___ ___ carry blood into the renal corpuscle and continue as glomerular capillaries.
afferent glomerular arterioles
Glomerular capillaries filter some of the ___ out of the blood and put it in the capsular space of Bowman's capsule, now called glomerular filtrate.
Glomerular capillaries continue as ___ ____ ____ as they leave the renal corpuscle
efferent glomerular arterioles
The blood in the efferent glomerular arterioles is still arterial, ___ exchange hasn't taken place yet. The only place in the body where blood entering and leaving capillaries is oxygenated blood.
Efferent glomerular arterioles divide to form the
Tubular reabsorption and secretion takes place here. Oxygen transfer to the cells of the nephron also takes place here.
Nerve supply to the kidneys is primarily from the ___ portion of the autonomic nervous system.
The sympathetic nervous system ___ the diameter of blood vessels to kidneys.
Is nerve supply essential for the kidney to function?
Glomerular capillaries contain many large ___ in capillary endothelium.
What forces plasma from the glomerulus out into the capsular space?
high blood pressure
Are fenestrations large enough to allow blood cells or large proteins to pass through?
How fast plasma is filtered through glomerulus. Depends on the rate of blood flow.
Glomerular filtration rate (GFR)
Abnormal amounts of protein in the urine can be used as an indicator of
Glomerular filtrate contains waste products that need to be cleared from the body. Glomerular filtrate is considered to be ___ the body.
____ is the mechanism to get useful substances in glomerular filtrate back into the body by way of the blood.
About 65% of all tubular reabsorption takes place in the
Substances to be reabsorbed pass out of the tubular lumen through or between tubular epithelial cells, then enter interstitial fluid and pass through endothelium into
Sodium has to be actively transported across cell membranes. Sodium attaches to a ___ protein.
Glucose and amino acids attach to the same carrier protein and follow sodium into the cell by passive transport. This is called
The amount of glucose that can be reabsorbed by the proximal convoluted tubules.
Renal threshold of glucose
If the blood glucose level gets too high, the amount of glucose filtered through the glomerulus exceeds the amount that can be reabsorbed, and the excess is lost in the
The renal threshold of glucose for dogs is
The normal blood glucose for dogs is
The renal threshold of glucose for cats is
The normal blood glucose for cats is
Sodium ions are also reabsorbed in the (2)
ascending loop of Henle
Sodium ions are reabsorbed in exchange for hydrogen, ammonium, or potassium ions under influence of what hormone?
Magnesium is reabsorbed from the PCT, ascending loop of Henle, and the
Potassium and calcium reabsorption takes place in the PCT, ascending loop of Henle, and
Calcium moves through the epithelial cells under the influence of what hormone?
parathyroid hormone (PTH)
During reabsorption, water follows the sodium, glucose, amino acids, and chloride into the interstitial space and peritubular capillaries by
Even though urea is a waste product, the body maintains a normal level of urea in blood, called
blood urea nitrogen (BUN)
Once water leaves the tubules during reabsorption, the concentration of other substances increases and they ____ diffuse out of the tubules.
The excess of urea or other nitrogenous compounds in the blood. Elevated BUN/CREA
Decreased blood flow to the kidneys due to dehydration, congestive heart failure and shock are causes of what type of azotemia?
The inability of the kidney to adequately regulate urine production because of damage to the nephrons, i.e., toxins, inflammation, infections are causes of what type of azotemia?
Obstruction that prevents urine from being expelled from the body (stones, blood clots, tumors) are causes of what type of azotemia?
Waste products not filtered from the blood in the glomerular capillaries pass through the peritubular capillaries into the
Secretion primarily occurs in the
Hydrogen, potassium, ammonium and urea are eliminated by
Some medications are eliminated from the body by secretion such as
penicillin and sulfonamides
When the tubular filtrate reaches the renal pelvis, it is considered
Urine volume is determined by the amount of ___ contained in the tubular filtrate when it reaches the renal pelvis.
Urine volume is controlled by what 2 hormones?
ADH & aldosterone
____ (hormone) acts on the DCT and collecting ducts to promote water reabsorption.
____ increases reabsorption of sodium. (hormone)
Etiology: pituitary (Lack of ADH) or nephrogenic (no response to ADH)
CSX: PU/PD, inability to concentrate urine
DX: modified water deprivation test
TX: dDAVP, continuous access to water
A continuation of the renal pelvis. Tube that exits the kidney at the hilus and connects to the urinary bladder.
The ureters continually move urine from the kidneys to the urinary bladder by
_____ epithelium allows ureters to stretch as urine passes through them on its way to the bladder.
Ureters enter the urinary bladder at an ____ angle.
This functions to collect, store, and release urine. It is composed of a muscular sac and neck.
The urinary bladder is lined with ___ epithelium that stretches as the bladder becomes filled with urine.
Wall of the urinary bladder contains ____ muscle bundles that run lenghtwise, obliquely, and in a circular direction
Neck of the bladder extends caudally from the sac into the __ canal and joins the urethra.
When the trigger point is reached, a spinal reflex returns a motor impulse to bladder muscles causing them to contract. This contraction gives the sensation of
having to urinate
____ control of the muscular sphincter around the neck of the bladder results in temporary control of urination.
Expulsion of urine from the urinary bladder into the urethra is called (2)
Micturition or uresis
The urethra is lined with ___ epithelium which allows it to expand.
The _____ urethra is shorter and straighter than the long, curved ____ urethra.
The sphincter at the neck of the urinary bladder closes at the beginning of ____ to prevent semen from entering the bladder and mixing with urine.
What are the 4 orders in the Reptilia class?
Crocodylia, Squamata, Chelonia, Rhynocephalia
Alligators, caimans, and crocodiles are in which order?
Snakes and lizards are in which order?
Turtles, tortoises & terrapins are in which order?
These types of animals, including reptiles, are unable to generate body heat internally. Body temp depends on environmental temp. 2 exceptions: leatherback sea turtles & pythons
Reptiles maintain body temps via _____ thermoregulation (basking, coiling).
Reptiles' ability to thermoregulate depends on access to temperatures within the
preferred optimal temperature zone (POTZ)
This is the range of temperatures in which the animal can perform all necessary metabolic functions
preferred optimal temperature zone (POTZ)
Ectotherms regulate temp depending on
Ectothermy allows many reptiles to survive on ___ amounts of food.
If temperatures are too ____, reptiles can suffer from digestive problems, immunosuppression, and other disorders.
If temps are too ___, reptiles are forced to maintain a high metabolic rate and may suffer from energy deficits.
Reptiles will undergo ____ or brumation when temps drop below POTZ.
The epidermis of reptiles is made of distinct scales formed by a ___ of the epidermis and is relatively impermeable.
This type of keratin on reptiles is soft, flexible, and found in the interscalar skin.
This type of keratin on reptiles in rigid and found in scales.
The dermis of reptiles is dense connective tissue that contains blood & lymph vessels, nerves and
The subcutaneous space in reptiles is _____, making SQ injections inadvisable.
The process of shedding the skin is controlled by the
Shed skin of reptiles is called
The process of shedding the skin is called
An enzyme-containing ___ is secreted between old and new epidermal layers during ecdysis.
During ecdysis, skin color ___ and spectale opacifies.
The term for abnormal shedding of the skin is
Causes of dysecdysis include (4)
low humidity, dehydration, underlying illness, lack of cage furniture
Tx for dysecdysis
proper husbandry, soaking
The iris of reptiles is made of skeletal muscle and is under ___ control.
Since the iris of reptiles is under voluntary control, ___ are not predictable.
Snakes and some lizards have this clear, scale-like structure formed by the fusion of the upper and lower eyelids instead of eyelids.
The spectacle is ___ to topical medications
Most reptiles have ____ developed extraocular muscles, with the exception of chameleons.
Chelonians have no ___ ___ so tears spill over the lid margin.
Most reptiles (exceptions: snakes & crocodilians) have ____ bones which help the eye maintain its shape.
Crocodilians are the only reptiles that have a ____ which help them see better in the dark.
This structure is found in tuataras and some lizards. It is a rudimentary retina & cornea with no iris, lids, or musculature. It may play a role in hormone production & thermoregulatory behavior.
The parietal eye is connected to the pineal body via the
The location of the heart varies in reptiles. For ____, the heart is on midline just caudal to the thoracic girdle and ventral to the lungs.
The location of the heart varies in reptiles. For most ____ the heart is within the thoracic girdle.
The location of the heart varies in reptiles. For ____ and some lizards, the heart is more caudal in the coelomic cavity.
The location of the heart varies in reptiles. For ____, the heart is usually at junction of first & second third of the body length but is fairly mobile.
The heart of most reptiles has ___ atria and __ ventricle.
There are 3 regions within the ventricle that are functionally separate. What are they?
In times of ___ ____, reptiles can shunt blood away from the lungs.
____ are the only reptiles that possess a four-chambered heart. It is very different from birds and mammals.
When the vagus nerve of lizards is suddenly stimulated, it sets off a chain of events within the body, most notably a rapid reduction of BP and HR. This is called
The vasovagal reflex is triggered by applying gentle pressure to both
Mature reptilian RBCs are different from mammalian in what 2 ways?
The WBC in reptiles that is analogous to neutrophils.
Because heterophils do not possess peroxidase & acid phosphatase which break down necrotic material, reptiles produce ___ pus instead of liquid material.
What are the different blood collection sites of reptiles? (5)
ventral coccygeal vein
dorsal coccygeal vein
Reptiles are capable of surviving long periods without breathing due to their large pulmonary volume, efficient ___ metabolism, and cardiac shunting capabilities.
Respiration in reptiles is driven by ___ levels in blood, as compared to CO2 levels in mammals.
Reptiles do not have an epiglottis, only a ___ in the rostral portion of the oral cavity.
Paired ___ cartilages border the glottal opening and open during respiration
The only vocalizations of reptiles are hissing, grunting, and bellowing. This is because they do not have
A glottal keel is present in some species of snakes. This increases
volume of vocalizations
Tracheal rings are ___ in chelonians and _____ in lizards and snakes.
complete - chelonians
incomplete - snakes & lizards
The ___ are analogous to alveoli in mammals. They are fixed structures (do not expand or contract) surrounded by capillaries.
This lung type is a simple, saclike structure. The cranial portion is the site of gas exchange. The caudal portion is avascular and comparable to avian air sac. Snakes and some lizards have this lung type.
This lung type is present is chelonians, some lizards, and crocodilians. It has many compartments and possesses intrapulmonary bronchi.
This lung type is present in iguanas and chameleons. It has characteristics of both unicameral & multicameral lungs.
Most snakes only have a single ___ lung.
There is no true ___ in reptiles that would separate the thoracic & abdominal cavity in mammals.
Since reptiles do not possess a true diaphragm, they have one cavity called
The single bone in the middle ear of reptiles is called
The columella connects to the tympanum and the ____ bone.
Since the columella articulates with the quadrate bone, it allows snakes to be very sensitive to ground vibrations transmitted through the
Concerning feeding, snakes & crocodilians are strict