Chapter 10: Homeostasis Flashcards
The _________________ consists of the kidneys, ureters, bladder, and urethra.
Excretory system
The ___________ is the kidney’s outermost layer.
Cortex
The ___________ of the kidney sits within the cortex.
Medulla
Each kidney has a renal _________, which is a deep slit in the centre of its medial surface.
Hilum
The widest part of the ureter, the _______________, spans almost the entire width of the renal hilum.
Renal pelvis
The renal artery, renal vein, and ureter enter and exit through the _____________.
Renal hilum
The renal artery branches out, passes through the medulla, and enters the cortex as __________________.
Afferent arterioles
The highly convoluted capillary tufts derived from the afferent arterioles (from renal artery) are known as ______________.
Glomeruli
After blood passes through a glomerulus, the ______________ then form a second capillary bed.
Efferent arterioles
The capillaries from the second capillary bed (from efferent arterioles) surround the loop of Henle and are known as _______________.
Vasa recta
Around the glomerulus is a cup-like structure known as _________________.
Bowman’s capsule
The bladder has a muscular lining known as the ________________.
Detrusor muscle
In order to leave the body, urine must pass through two sphincters - the ___________________ and _________________.
- Internal urethral sphincter
- External urethral sphincter
The _________________, consisting of smooth muscle, is contracted in its normal state. It is under involuntary control.
Internal urethral sphincter
The ________________ consists of skeletal muscle and is under voluntary control.
External urethral sphincter
When bladder is full, stretch receptors convey to nervous system that the bladder requires emptying. This causes parasympathetic neurons to fire, and the detrusor muscle contracts. This contraction also causes the internal sphincter to relax. This reflex is known as the ________________.
Micturition reflex
Kidney function may be divided into three different processes: ___________, ___________, and _______________.
- Filtration
- Secretion
- Reabsorption
The nephron’s first function is _____________.
Filtration
In the kidneys, approximately 20% of the blood that passes through the glomerulus is filtered as fluid into Bowman’s space. The collected fluid is known as the ____________.
Filtrate
The movement of fluid into Bowman’s space is governed by _______________, which account for the pressure differentials in both hydrostatic and oncotic pressures between the blood and Bowman’s space.
Starling forces
The hydrostatic pressure in the glomerulus is significantly (higher?/lower?)______________ than that in Bowman’s space, which causes fluid to move into the nephron.
Higher
Ammonia is a byproduct of the metabolism of nitrogen-containing compounds and, as a base, can disturb the pH of blood and cells. The liver converts the ammonia to ___________, a neutral compound, which travels to the kidney and is secrete into the nephron for excretion in the urine.
Urea
_____________ is the movement of solutes from blood to filtrate at Bowman’s capsule.
Filtration
_____________ is the movement of solutes from blood to filtrate anywhere besides Bowman’s capsule.
Secretion
_____________ is the movement of solutes from filtrate to blood.
Reabsorption
__________________ (______) is where amino acids, glucose, water-soluble vitamins, and the majority of salts are reabsorbed along with water.
Proximal convoluted tubule (PCT)
Solutes that enter the _____________ - the connective tissue surrounding the nephron - are picked up by vasa recta to be returned to the bloodstream for reuse within the body.
Interstitium
Major waste products excreted in the urine: Dump the HUNK
- H+
- Urea
- NH3 (Ammonia)
- K+ (potassium)
Filtrate from the proximal convoluted tubule (PCT) then enters the _____________________, which dives deep into the medulla before turning around to become the ______________________.
- Descending limb of the loop of Henle
- Ascending limb of the loop of Henle
Together, the vasa recta and nephron create a ______________________.
Countercurrent multiplier system
The ___________________ is only permeable to salts and is impermeable to water.
Ascending limb of the loop of Henle
While the __________________ maximizes water reabsorption by taking advantage of increasing medullary osmolarity, the __________________ maximizes salt reabsorption by taking advantage of decreasing medullary osmolarity.
- Descending limb of the loop of Henle
- Ascending limb of the loop of Henle
At the transition from the inner to outer medulla, the loop of Henle becomes thicker in what is termed the _______________.
Diluting segment
The __________________ (______) responds to aldosterone, which promotes sodium reabsorption.
Distal convoluted tubule (DCT)
Because the sodium ions are osmotically active particles, water will follow the sodium, concentrating the urine and decreasing its volume in the ____________________ (______).
Distal convoluted tubule (DCT)
The final concentration of urine will depend largely on the permeability of the _____________, which is responsive to both aldosterone and antidiuretic hormone (ADH or vasopressin).
Collecting duct
When the body is very well hydrated, the _______________ will be fairly impermeable to salt and water.
Collecting duct
_____________ is a steroid hormone that is secreted by the adrenal cortex in response to decreased blood pressure.
Aldosterone
Decreased blood pressure stimulates the release of ____________ from ____________ cells in the kidneys.
- Renin
- Juxtaglomerular cells
Renin cleaves ________________, a liver protein, to form angiotensin I.
Angiotensinogen
Angiotensin I peptide is metabolized by ____________________ (_____) in the lungs to form angiotensin II, which promotes the release of aldosterone from the adrenal cortex.
Angiotensin converting enzyme (ACE)
_____________ works by altering the ability of the distal convoluted tubule and collect duct to reabsorb sodium. As sodium is reabsorbed, water will flow with it. It also increase potassium and hydrogen ion excretion.
Aldosterone
______________ (_______, also known as _____________) is a peptide hormone synthesized by the hypothalamus and released by the posterior pituitary in response to high blood osmolarity.
Antidiuretic hormone (ADH, also known as vasopressin)
______________ (______) directly alters the permeability of the collecting duct, allowing more water to be reabsorbed by making the cell junctions of the duct leaky.
Antidiuretic hormone (ADH)
Alcohol and caffeine both inhibit _______________ release and lead to the frequent excretion of dilute urine.
Antidiuretic hormone (ADH)
Vasoconstriction will secondarily lead to _________ release, which will help raise blood pressure.
Renin
____________ pressure is the “sucking” pressure that draws water into the vasculature caused by all dissolved particles.
Osmotic pressure
__________ pressure is the osmotic pressure that is attributable to dissolved proteins specifically.
Oncotic pressure
The ____________ buffer system is the major regulator of blood pH.
Bicarbonate buffer system
When blood pH is too low, the kidneys excrete more _____________ and increase reabsorption of bicarbonate, resulting in a higher pH.
Hydrogen ions
When blood pH is too high, the kidneys can excrete more _____________ and increase the reabsorption of hydrogen ions.
Bicarbonate
By both weight and size, the __________ (__________) is the largest organ in our bodies.
Skin (integument)
Starting from the deepest layer and working outward, the skin layers are: ______________ (_____________ layer), ______________, and _____________.
- Hypodermis (subcutaneous layer)
- Dermis
- Epidermis
The epidermis is subdivided into layers called ___________.
Strata
Layers of the skin (superficial to deep):
Come, Let’s Get Sun Burned
- Strata corneum
- Strata lucidum
- Strata granulosum
- Strata spinosum
- Strata basale
The ________________ contains stem cells and is responsible for proliferation of keratinocytes, the predominant cells of the skin, that produce keratin.
Strata basale
In the ________________, these cells become connected to each other; this layer is also the site of Langerhans cells.
Stratum spinosum
_____________ cells are actually special macrophages that reside within stratum spinosum. These cells are capable of presenting antigens to T-cells in order to activate the immune system.
Langerhans cells
In the _____________, the keratinocytes die and lose their nuclei.
Stratum granulosum
The _____________ is only present in thick, hairless skin, such as on the sole of the foot or the palms, and is nearly transparent.
Stratum lucidum
The ______________ contains up to several dozen layers of flattened keratinocytes, forming a barrier that prevents invasion by pathogens and that helps to prevent loss of fluids and salt.
Strata corneum
In the epidermis, the main cells are _______________.
Keratinocytes
____________ is resistant to damage and provides protection against injury, water, and pathogens for the skin.
Keratin
___________ form from excessive keratin deposition in areas of repeated strain due to friction; they provide protection to avoid damage in the future.
Calluses
Fingernails and hair are formed from ___________ and are produced by specialized cells in the skin.
Keratin
___________ are a cell type derived from neural crest cells and found in the stratum basale.
Melanocytes
Melanocytes produce ____________, a pigment that serves to protect the skin from DNA damage caused by ultraviolet radiation.
Melanin
The upper layer of the dermis (right below the epidermis) is the ______________, which consists of loose connective tissue.
Papillary layer
Below the papillary layer is the denser ______________.
Reticular layer
Sweat glands, blood vessels, and hair follicles originate in the __________.
Dermis
Most sensory receptors are located in the ___________.
Dermis
_____________ (______) are sensory receptors present at the epidermal-dermal junction.
Merkel cells (discs)
Other sensory organs in the skin include free nerve endings, which respond to pain; ______________, which respond to light touch; and _______________, which respond to stretch; and _______________, which respond to deep pressure and vibration.
- Meissner’s corpuscles
- Ruffini endings
- Pacinian corpuscles
The ____________ is a layer of connective tissue that connects the skin to the rest of the body. This layer contains fat and fibrous tissue.
Hypodermis
_______________ is achieved by sweating, piloerection, vasodilation, and vasoconstriction.
Thermoregulation
_____________ is an excellent cooling mechanism that is controlled by the autonomic nervous system.
Sweating
In cold conditions, ____________ muscles contract, causing the hairs of the skin to stand up on end (____________)
- Arrector pilli
- Piloerection
____________ requires a sizeable amount of ATP; however, a significant portion of the energy from ATP is converted into thermal energy.
Shivering
