3.1 - Internal Surfaces of the Body Flashcards
What would you call the functional tissue of an organ (as opposed to the supportive or connective tissue)?
Parenchyma
What would you call the supportive or connective tissue of an organ (as opposed to the functional tissue)?
Stroma
What type of tissue forms the parenchyma of glands?
Epithelium
What type of tissue forms stroma (supportive tissue)?
Connective
What type of tissue allows movement?
Muscle
What type of tissue facilitates information processing and communication?
Nerve
List 4 tracts lined by mucous membranes.
- GI tract
- Respiratory tract
- Urinary tract
- Reproductive tract
Where would you find muscularis mucosa?
GI tract
What is the adventitia?
A layer of connective tissue that anchors organs to surrounding structures
How do serous membranes develop?
During embryonic development, the heart, lungs, and gut develop next to a bag-like cavity into which they invaginate (visualize: a fist in a balloon)
What are the two layers of serous membranes?
- Visceral
2. Parietal
List 3 structures enveloped by serous membranes.
- Peritoneum
- Pleural sac
- Pericardial sac
How do serosa ease the movement of the structures they surround?
Secrete lubricating fluid that reduces friction
Which peritoneal organ is enveloped by serosa on the superior surface and adventitia on the inferior surface?
Bladder
What are the 4 layers of the gut wall? (Hint: needs to move.)
- Mucosa
- Sub-mucosa
- Muscularis externa
- SEROSA
What are Peyer’s patches?
Masses of lymphatic tissue found in the ileum
What is the function of Peyer’s patches?
Immune surveillance
Which layer of the GI wall moves food via peristalsis?
Muscularis externa
Which branch of the nervous system control peristaltic movement?
Parasympathetic nervous system
You are looking at a histological image of esophageal mucosa. Which layer contains many cells of the immune system?
Lamina propria
What are the 4 layers of the esophagus?
- Mucosa
- Sub-mucosa
- Muscularis externa
- ADVENTITIA
Why is the esophagus surrounded by adventitia rather than serosa?
To anchor it in place
Why is the skeletal muscle in the upper regions of the esophagus progressively replaced with smooth muscle?
Swallowing begins with voluntary muscle action, but transitions to involuntary action as it moves further down
What type of epithelium lines most of the gut?
Simple columnar epithelium
Define gastric.
Relating to the stomach
What are rugae?
Folds of gastric muscosa
Where would you find rugae?
Stomach (more specifically, gastric mucosa)
Which structure of the stomach allows it to expand?
Rugae
Where would you find Brunner’s glands?
Duodenum
What is the function of Brunner’s glands?
Secrete alkaline mucin to counteract acidic chime, protecting the mucus membranes
What are gastric pits?
Indentations in the stomach which denote entrances to gastric glands
List 2 digestive enzymes.
- Pepsinogen
2. Gastric lipase
What is the function of the hormone gastrin?
Digestion
List 4 substances secreted by gastric glands.
- Mucus
- HCl
- Digestive enzymes (e.g., pepsinogen and gastric lipase)
- Digestive hormones (e.g., gastrin)
How frequently do stomach glands turnover?
4-7 days
What are the 4 regions of the stomach?
- Cardia
- Fundus
- Body
- Pylorus
Which 2 regions of the stomach contain gastric glands?
- Fundus
2. Body
What is the main function of the pylorus and cardia?
Mucus production
Which glands of the duodenum create optimum pH for digestion?
Brunner’s glands
In which part of the small intestine are plicae circulares most abundant?
Jejunum
What is another name for glands found in the intestine?
Crypts of Lieberkühn
Why does the colon have fewer plicae circulares and no villi?
Main function is waste production, not nutrient absorption
Why are goblet cells in the colon highly productive?
Must produce mucus to aid in the passage of stools
What do the epithelial cells of the colon absorb?
- Water
2. Remaining electrolytes
What are teniae coli?
Three longitudinal bands of smooth muscle on the colon
In the colon, the muscularis externa changes, and the longitudinal muscle forms three bands known as ___.
Teniae coli
Why does epithelia transition from columnar to stratified squamous non-keratinized at the recto-anal junction?
Function shifts from absorptive to protective
The CONDUCTING portion of the respiratory tract extends from the ___ to the ___.
Nasal cavity
Bronchioles
The RESPIRATORY portion of the respiratory tract extends from the ___ to the ___.
Respiratory bronchioles
Alveoli
Where would you find olfactory chemoreceptors? (Hint: site of smell.)
Olfactory epithelium
What type of epithelium lines the nasal cavity?
Pseudostratified columnar ciliated
Where are Bowman’s glands found?
Olfactory mucosa
Classify the structure of Bowman’s glands
Branched tubuloalveolar
What is the function of Bowman’s glands?
Produce fluid to dissolve odiferous substances
What is another term for olfactory glands?
Bowman’s glands
Why does air get warmer as it passes the nasal cavity?
Area is highly vascularized
What type of epithelium lines the trachea?
Pseudostratified columnar ciliated
What holds the trachea open?
Rings of C-shaped cartilage
Which muscle bridges the gap between the ends of C-shaped cartilage in the trachea?
Trachealis muscle
What happens to the C-shaped cartilage ring in trachea with aging?
Becomes partially ossified
With aging, the C-shaped cartilage ring in trachea becomes partially ossified. What impact does this have?
Harder to swallow or cough due to rigidity
What type of epithelium would you find at the head of the bronchus?
Pseudostratified columnar ciliated
What are pneumocytes?
Epithelial cells of the alveoli
What is the role of surfactants?
Lower surface tension
List 3 types of cells found in the alveolar lining.
- Type I pneumocytes
- Type II pneumocytes
- Macrophages
Compare the structure of type I pneumocytes and type II pneumocytes.
Type I: simple squamous
Type II: cuboidal
Compare the alveolar area covered by type I pneumocytes and type II pneumocytes.
Type I: 90%
Type II: 10%
Compare the function of type I pneumocytes and type II pneumocytes.
Type I: gas exchange
Type II: produce surfactant
What is the role of macrophages in the alveoli?
Phagocytose foreign particles
How long do erythrocytes spend in the alveolar capillaries?
< 1 second
Which cup-like sack performs the first step in the filtration of blood to form urine?
Bowman’s capsule
Why can a needle only be inserted in a full bladder?
Empty bladder is covered by pubic symphysis
Place the following structures in the correct order (re: path of urine).
- Collecting ducts
- Calyces
- Ureter
- DCT
- Renal papillae
DCT -> Collecting ducts -> Renal papillae -> Calyces -> Ureter
What type of epithelium lines the distal convoluted tubules?
Simple cuboidal
What type of epithelium lines the calyces and ureter?
Transitional
Compare the functions of the male urethra and female urethra.
Male: urinary, reproductive
Female: urinary
The distal urethra contains which rare type of epithelium?
Stratified columnar
What type of tissue would you find in the sub-mucosa?
Connective
List 2 structures where you would find c-shaped cartilage.
- Trachea
2. Bronchi
