Final Exam Flashcards
Kidneys
Located retroperitoneally
- *Renal capsule**-surrounds the kidney-fibrous sac
- *Adipose capsule**- contains perirenal fat
- *Renal fascia**- anchors to parietal peritoneum and deep fascia of lumbar muscles.
- *Kidneys**
- Excretion (filter fluids and eliminate from body)
- Regulate volume and blood pressure of blood
- Maintain proper balance of water, salts, acids, and bases
- *Main waste products**
- Urea (from protein breakdown)
- uric acid (nucleic acid breakdown)
- creatinine (breakdown of creatine phosphate in muscles)
Anatomy of Kidney
Cortex
medulla
renal pyramids-striated due to tubules
Papilla- the pyramid’s apex points internally
Renal columns- inward extensions of the renal cortex, separate adjacent pyramids
Lobes- a single medullary pyramid plus the cortical tissue surrounding it.
Hilus – on concave surface
Vessels, ureters, lymphatics and nerves enter and exit
- *Renal pelvis**- flat, funnel-shaped tube, expanded superior part of the ureter
- *Major calices (calyx)**- branching extensions of the renal pelvis. Forms minor calices.
- *Minor calices**- cup shaped tubes that enclose the papillae of the pyramids. Collect urine draining from papillae and empty it into renal pelvis
- *Nephron** (the functional unit of the kidney)
- *Renal corpuscle** (located where it is labeled “cortical nephron”)
- *Glomerulus**
- *Glomerular capsule**
- *Renal (uriniferous) tubule**
- *Proximal Convoluded Tubule**
- *Nephron loop** (“loop of Henle”)
- *Distal Proximal Convoluded Tubule**
- *Collecting duct** (not part of the nephron, but attaches to many nephrons)
FLOW
Note: no segmental vein
Mechanisms of Urine Production
- *Filtration** – filtrate of blood leaves kidney capillaries. Resembles blood plasma but free of cells and lower in protein; “glomerular filtrate”.
- *Reabsorption** – most nutrients, water, and essential ions reclaimed (99% of volume reabsorbed). Occurs throughout renal tubule.
- *Secretion** – active process of removing undesirable molecules from the blood of surrounding capillaries (drugs, antibiotics, toxins, hydrogen ions, etc.)
Renal corpuscle = glomerulus and glomerular capsule
Glomerulus – tuft of capillaries
Capillaries are fenestrated (porus).
Afferent (arise from cortical raiate arteries) and efferent arterioles.
High-resistance vessels. Efferent is narrower than afferent arteriole and so blood pressure is EXTREMELY high in glomerulus.
Glomerular (Bowman’s) capsule-
Parietal layer – simple squamous epithelium
Visceral layer – consists of podocytes- podocytes have pedicels that interdigitate with one another. Filtrate passes into capsular space through filtration slits between pedicels
Filtration Membrane
- *Filtration Membrane- 3 parts**
- Fenestrated endothelium of capillary
- Filtration slits on pedicels of podocytes: each covered by slit diaphragm.
- Intervening basement membrane formed from basal laminae (just protein and carbohydrate sheet) of endothelium and podocyte epithelium
Proximal Convoluted Tubule
Filtrate proceeds to renal tubules from glomerulus
confined to renal cortex.
most active in reabsorption (and secretion as secondary action).
Cuboidal epithelial cells with long microvilli to maximize reabsorbing capacity.
Have many mitochondrial to provide energy.
Loop of Henle
Simple cuboidal to simple squamous to simple cuboidal
- *Thin decending segment**- only permiable to water, reabsorption of water from tubular fluid.
- *Thick ascending limb**- only reabsorption of ions; assists in creation of a concentration gradient in the medulla.
- *Cortical or juxtamedullary nephrons-** depend on length of the loop of henle
note:
-the lower the loop goes: the more concentrated the pee.
Nephrons: 85% corticol-short loop, 15% juxtamed.-long
Distal Convoluted Tubule
- *Distal convoluted tubule** –Simple cuboidal epithelium.
- No microvilli
- Continues as “diluting segment”
- Reabsorption of solutes; water is variable and dependent on hormones (sodium and calcium)
- Part of the juxtaglomerular apparatus-functions in the regulation of blood pressure and is an area of specialized contact between distal convoluted tubule and afferent arteriole
Note: know ADH(Neurohypophisis–> kidneys to uptake water) & Aldosterone (Adrenal cortex-kidneys to uptake salt)
Juxtaglomerular Apparatus
- *Juxtaglomerular cells** in afferent arteriole– detect falling blood pressure, and secrete renin in response
- *Macula densa** – portion of distal convoluted tubule
- Tall, closely packed epithelial cells
- Act as chemoreceptors – sense when solute concentrations fall below critical level. Signal juxtaglomular cells to secrete renin (targets the renal cortex to secrete aldosterone which makes the kidneys reabsorb salt and thus water bringing up blood voume and pressure)
Note: Dieretics target the DCT to prevent the uptaking of sodium, and thus water.
Collecting Tubules (Collecting ducts)
- Collecting tubules – receive urine from distal convoluted tubules.
- Run from cortex into the deep medulla. Adjacent collecting tubules form larger papillary ducts that empty into minor calices through the renal papillae.
- Made of simple cuboidal epithelium which thickens to form simple columnar papillary ducts.
Urinary Bladder
3 layers:
Mucosa with distensible transitional epithelium and lamina propria
-Thick muscular layer (detrusor muscle)- smooth muscle fibers arranged in inner and outer longitudinal layers and a middle circular layer.
-Fibrous adventitia (superior surface is parietal peritoneum).
-Trigone
-Prostate gland
Urethra
-Transitional to stratified squamous (in to out)
-Internal urethral sphincter –involuntary smooth muscle that keeps urethra closed in between voidings
-External urethral sphincter (voluntary control)
In females –opens to external urethral orifice just anterior to vaginal opening and posterior to clitoris.
In males – three named regions
-Prostatic urethra – passes through the prostate gland
-Membranous urethra – through the urogenital diaphragm
-Spongy (penile) urethra – passes through the length of the penis and opens at external urethral orifice.
Carries both semen and urine (not simultaneously)
Digestive System
Organs are divided into two groups:
The alimentary canal
Mouth, pharynx, and esophagus
Stomach, small intestine, and large intestine (colon)
Rectum and anal canal
Accessory digestive organs (not part of the tube)
Teeth and tongue
Gallbladder, salivary glands, liver, and pancreas
Histology of the Alimentary Canal Wall
- Serosa (in abdominal cavity) vs. adventitia- outside of abdominal cavity loose fibrous connective tissue) vs. both
- Longitudinal muscle (muscularis externa)
- Myenteric (Auerbach’s) nerve plexus
- Circular muscle (muscularis externa)
- Submucosa
- Submucosal (Meissner’s) nerve plexus
- Muscularis mucosae
- lamina propria
- Epithelial lining
Nervous System of Gut
Gut has it’s own nervous system:
Intrinsic -Enteric Nervous System- Submucosal nerve plexus & myenteric nerve plexus
- *Extrinsic**- (ANS) sympathetic (slow down) and parasympathetic (speed up)
- can influence/override Enteric Nervous system
- *Sympathetic**- inhibit muscle contractions (peristalsis) and prevent enzyme secretion
- *Parasympathetic**- opposite (speed up digestion)
Tone= contraction
Extrinsic control from Sympathetic and parasympathetic
Parasympathetic
-Vagus is 75% afferent and 25% efferent
Sympathetic
50/50 afferent and efferent
Peritoneal Cavity and Peritoneum
- *Peritoneum** – a serous membrane
- *-Visceral peritoneum** – surrounds digestive organs
- *-Parietal peritoneum** – lines the body wall
- *Peritoneal cavity** – a slit-like potential space
- *Peritoneal fluid**- a lubricating serous fluid secreted by the peritoneum
- *Mesentery** – a double layer of peritoneum that extends to the digestive system from the body wall
- Holds organs in place
- Sites of fat storage
- Provides a route for circulatory vessels and nerves
Dorsal Mesentary- attaches organ to the posterior wall of the cavity.
Ventral Mesentary- attaches organ to the ventral wall of cavity
Mesenteries
- *Ventral mesenteries**-
- Falciform ligament
- Lesser omentum
- *Dorsal mesenteries**
- Greater omentum (roundabout way)
- Mesentery proper (in the coils between jejunum and ileum)
- Transverse mesocolon from transverse colon
- Sigmoid mesocolon from sigmoid colon
The Mouth and Associated Organs
The mouth – oral cavity
Mucosal layer
Stratified squamous epithelium
Lamina propria (MALT-mucosa associated lymphoid tissue)
The lips and cheeks
Formed from orbicularis oris and buccinator muscles, respectively
- *Uvula**- keeps food out of the nasopharynx
- *Palatoglossal arches** -mark end of oral cavity and the beginning of the oropharynx
- *Palatopharyngeal arches** (in oropharynx)
The Superior Surface of the Tongue
Tongue (stratified squamous)
• Tongue papillae
– Filiform papillae- “rough tongue”(most abundant)
– Fungiform papillae-”mushrooms”(dispersed among filiform p.)
– Circumvallate papillae- v-shaped row
– Sulcus terminalis- border of mouth and pharynx
– Lingual tonsils- big bumps on the back of the tongue
Note: Tastebuds are on papillae
Teeth for Mastication
Permanent dentition- (2I, 2C, 2P, 3M) x4=32
Crown, neck, root
Dentin-bonelike and collagen components, harder than bone covered with enamel on crown and cementum on root
Periodontal ligament-tooth to jaw bone
Gingiva-gum
The Salivary Glands
-Produce saliva; moistens mouth
Water, ions, mucus, enzymes (digestive and anti-bacterial), antibiotics
-Starts digestion of food (enzyme: amylase- breaks down carbohydrates, and only carbohydrates, in the mouth)
–Parotid- only serous cells (water and enzymes)
–Submandibular – serous fliud and mucous
–Sublingual glands- mostly mucous cells
–Parasympathetic (promotes) and sympathetic innervation