Homeostasis

Question 1

serves many functions, including the regulation of blood pressure, blood osmolarity, acid-base balance, and removal of nitrogenous wastes

Answer 1

excretory system

Question 2

flow of urine

Answer 2

Question 3

has a muscular lining known as the detrusor muscle, which is under parasympathetic control; has two muscular sphincters

Answer 3

bladder

Question 4

bladder:

consists of smooth muscle and is under involuntary (parasympathetic) control

Answer 4

internal urethral sphincter

Question 5

bladder:

consists of skeletal muscle and is under voluntary (sympathetic ) control

Answer 5

external urethral sphincter

Question 6

contains a cortex (outer portion) and a medulla (inner portion), and has a hilum which contains a renal artery, renal vein, and ureter; produces urine, contains a portal system, participates in solute movement, functional unit is the nephron, is under hormonal control and can regulate pH

Answer 6

kidney

Question 7

kidney:
has two capillary beds in series in the kidney; blood from renal artery flows through afferent arterioles, which form glomeruli in Bowman’s capsule (the first capillary bed); blood then flows through efferent arteriole to the vasa recta (the second capillary bed), which surround the nephron; blood leaves the kidney through the renal vein

Answer 7

renal portal system

Question 8

kidney:

kidney function of regulating blood volume and osmolarity; occurs through three processes in the kidney

Answer 8

solute movement

Question 9

solute movement:
the movement of solutes from blood to filtrate at Bowman’s capsule; the direction and rate is determined by Starling forces which account for the hydrostatic and oncotic pressure differentials between the glomerulus and Bowman’s space

Answer 9

filtration

Question 10

solute movement:

the movement of solutes from blood to filtrate anywhere other than Bowman’s capsule

Answer 10

secretion

Question 11

solute movement:

the movement of solutes from filtrate to blood

Answer 11

reabsorption

Question 12

kidney:

functional unit of the kidney, about a million of them; has five segments each with specific function

Answer 12

nephron

Question 13

nephron:

first part of nephron where blood is initially filtered to form filtrate

Answer 13

Bowman’s capsule

Question 14

nephron:
a network of small blood vessels (capillaries), known as a tuft, that prevents entry of large molecules, such as proteins, into filtrate

Answer 14

glomerulus

Question 15

nephron:
the site of bulk reabsorption of glucose, amino acids, soluble vitamins, salt, and water; also site of secretion for hydrogen ions (H+), urea, ammonia (NH3), and potassium ions (K+)

Answer 15

proximal convoluted tube (PCT)

Question 16

proximal convoluted tube (PCT) mnemonic

Answer 16

dump the HUNK:

H (H+ ions), U (urea), N (NH3), K (K+ ions)

Question 17

nephron:
permeable to water but not salt; therefore, as the filtrate moves into the more osmotically concentrated renal medulla, water is reabsorbed from the filtrate; the vasa recta and nephron flow in opposite directions, creating a countercurrent multiplier system that allows maximal reabsorption of water

Answer 17

descending limb of the loop of Henle

Question 18

nephron:
permeable to salt but not water; therefore, salt is reabsorbed both passively and actively; the diluting segment is in the outer medulla; because salt is actively reabsorbed in this site, the filtrate actually becomes hypotonic compared to the blood

Answer 18

ascending limb of the loop of Henle

Question 19

nephron:

is responsive to aldosterone and is a site of salt reabsorption and waste product excretion

Answer 19

distal convoluted tube (DCT)

Question 20

nephron:
is responsive to both aldosterone and antidiuretic hormone (ADH or vasopressin) and has variable permeability, which allows reabsorption of the right amount of water depending on the body’s needs

Answer 20

collecting duct

Question 21

kidney:

control the kidney; when blood pressure (and volume) are low, two different ____ systems are activated

Answer 21

hormones (hormonal)

Question 22

hormone:
a steroid hormone regulated by the renin-angiotensin-____ system that increases sodium reabsorption in the distal convoluted tubule and collecting duct, thereby increasing water reabsorption; results in an increased blood volume (and pressure), but no change in blood osmolarity

Answer 22

aldosterone

Question 23

hormone:
a peptide hormone synthesized by the hypothalamus and released by the posterior pituitary; its release is stimulated not only by low blood volume but also by high blood osmolarity; it increases the permeability of the collecting duct to water, increasing water reabsorption; results in an increased blood volume (and pressure) and decreased blood osmolarity

Answer 23

antidiuretic hormone (ADH or vasopressin)

Question 24

kidney:

kidney function by selective reabsorption or secretion of bicarbonate (HCO3-) or hydrogen ions (H+)

Answer 24

pH regulation

Question 25

the largest organ in the body; acts as a barrier, protecting us from the elements and invasion by pathogens; functions in thermoregulation and preventing dehydration and salt loss from the body; composed of three major layers: epidermis, dermis, and hypodermis (subcutaneous)

Answer 25

skin (integument)

Question 26

layer of skin:
composed of five layers: stratum basale, stratum spinosum, stratum granulosum, stratum lucidum, and stratum corneum; also contains keratinocytes, melanocytes, and Langerhans cells
mnemonic for layers: Come, Let’s Get Sun Burned (superficial to deep)

Answer 26

epidermis

Question 27

cell type in epidermis:

predominant cell of skin that produces keratin

Answer 27

keratinocytes

Question 28

cell type in epidermis:
cells that produce melanin, which protects the skin from DNA damage caused by ultraviolet radiation; melanin is passed to keratinocytes

Answer 28

melanocytes

Question 29

cell type in epidermis:

cells that are special macrophages that serve as antigen-presenting cells in the skin (subset of dendritic cells)

Answer 29

Langerhans cells

Question 30

layer of skin:

composed of two layers: the papillary layer and the reticular layer

Answer 30

dermis

Question 31

cell type in dermis:
many receptors contained in the dermis, including Merkel cells (deep pressure and texture), free nerve endings (pain), Meissner’s corpuscles (light touch), Ruffini endings (stretch), and Pacinian corpuscles (deep pressure and vibration)

Answer 31

sensory cells

Question 32

layer of skin:

contains fat and connective tissue and connects the skin to the rest of the body

Answer 32

hypodermis

Question 33

function of skin in maintenance of a constant internal temperature

Answer 33

thermoregulation

Question 34

thermoregulation:

include sweating, which draws heat from the body through evaporation of water form sweat, and vasodilation

Answer 34

cooling mechanisms

Question 35

thermoregulation:
include piloerection, in which arrector pili muscles contract causing hairs to stand on end (trapping a layer of warm air around the skin), vasoconstriction, shivering, and insulation provided by fat

Answer 35

warming mechanisms