Week 3 Flashcards
What are 3 layers of Mucosa
Epithelium, lamina propia, muscularis Mucosae
In the epithelium layer of mucosa, there are two layers:
- _______ (in mouth, esophagus & anus) = tough.
- _______ in the rest = secretes enzymes and absorbs nutrients
- specialized cells (____) secrete mucus onto cell surfaces
_______ cells—secrete hormones controlling organ function
- Stratified Squamous
- Simple Columnar
- Goblet
- Enteroendocrine
The Lamina Propia layer of Mucosa contains:
Layer of loose connective tissue – contains BV and lymphatic tissue (MALT) and IgA’s
The Muscularis mucosae layer of Mucosa contains:
Thin layer of ____ muscle – causes folds to form in mucosal layer – increases local movements to ensure that all ______ cells are fully exposed to contents of GI tract
- smooth
2. absorptive
The Submucosa:
Loose _____ tissue – containing BV, glands lymphatic tissue, and network of neurons
• Submucosal plexus (_____ plexus)— • Controls secretions in mucosal epithelium
- Connective
2. Meissner’s
The muscularis contains 3 layers:
Skeletal, Smooth, Myenteric Plexus (Auerbach’s plexus)
Layers of Muscularis:
• Skeletal muscle = voluntary control – in mouth, pharynx , upper esophagus and anus – control over _________
• Smooth muscle = involuntary control – made of _____ and mixes, crushes & propels food along by peristalsis
• Myenteric Plexus (Auerbach’s plexus) – both parasympathetic & sympathetic innervation of circular and longitudinal ____ muscle layers
- swallowing and defecation
- inner circular fibers & outer longitudinal fibers
- smooth
Serosa (visceral peritoneum):
• Thin layer of loose CT covered by simple ____ epithelium (mesothelium)
• Covers all organs and walls of cavities not open to the outside of the body
• Also sometimes called the _____ (when the organ is bound to other structures)
- Squamous
2. Adventitia
The ____ is a straight, collapsible, tube. ____ waves move food though the tube. Mucous glands are scattered throughout the submucosa.
Contains _______ (LES)
- esophagus
- Peristalic
- Loweresophageal sphincter
The stomach stretches due to?
rugae
Parts of stomach: cardia, _____, body, pylorus. It empties as small squirts of ____ and leaves the stomach through the pyloric valve.
- fundus
2. chyme
The stomach acidifies and converts the bolus into a thick, viscous fluid known as _____.
chyme
In which parts of the stomach can you find rugae?
Rugae are folds of the mucosa and submucosa.
The stomach has many gastric pits which are shallow in the cardia and fundus and deepest in the _____. Glands in the cardia and pylorus are more ____ tubular vs. body/ fundus.
- pylorus
2. COILED
3 layers of the muscularis externa:
• Inner oblique layer
• Middle circular layer that forms _______
• Outer _______
- the pyloric sphincter
2. longitudinal layer
Parietal cells secrete _______, important for vitamin ___ absorption
- hydrochloric acid and intrinsic factor
2. B12
Parietal and chief cells of stomach are mostly found in the ?
They are found mostly in the body and fundus
What do cheif cells of the stomach secrete?
pepsinogen and gastric lipase
G cells of the stomach are found in the ____ and secrete ____
- Pylorus
2. the hormone: gastrin
Parietal Cells of the stomach produce:
_______ (gives stomach its acid environment) & converts pepsinogen made from ____ to pepsin (the active form of the enzyme)
_______ absorption of vitamin B12 for RBC production
- Hydrochloric acid
- Chief cells
- Intrinsic factor
Gastrin hormone (g cell) – “get it out of here”
• release more gastric juice (HCl from ___ cell)
• increase gastric motility
• relax ____ sphincter
• constrict ____ sphincter preventing entry
- Parietal
- pyloric
- esophageal
Mucous cells – form a protective barrier to prevent digestion of stomach wall. Surface cells are very ___ and secrete _____ as well.
- alkaline
2. lysozyme
Chief cells – secrete _____ (inactive enzyme) & gastric ___
- pepsinogen
2. lipase
Gastric pits in the fundus are called ____
foveolus; in a faveolus a parietal cell is oxyntic and cheif cells are peptic
The small intestines are ____ long
Major role in ______
3 parts:
- 20 feet
- absorption
- duodenum, jejunum, ilium
There are three parts to the small intestine, which is the shortest? longest?
The duodenum is 10 inches (shortest)
Next is jejunum 8 feet
Finally the ileum is 12 feet (longest)
What marks the end of the small intestine?
The iliocecal valve
3 important modifications in small intestine that increase surface area for absorption
plicae circularis, villi, and microvilli
In the small intestine, ______ are permanent ½ inch tall folds of the mucosa and submucosa. Increases surface area 2 to 3-fold
(It can not stretch out like rugae in stomach)
Plicae circularis
In the small intestine, ______ are permanent evaginations that contains vascular capillaries and ___ (lymphatic capillaries) in the lamina propria. Increases surface area 10-fold
- Villi
2. Lacteals
In the small intestine, ______ are cell surface feature of the epithelial cells that contain actin filaments – known as ______
(Increase surface area 20-fold)
- Microvilli
2. Brush border
Mechanical breakdown of small intestine includes:
•______: localized contractions that slosh chyme back & forth, mixing it with digestive juices to bring food into contact w/ mucosa
• _____: begins after most of a meal has been absorbed; pushes food along.
• Chyme remains in the small intestine for 3-5 hours
- Segmentation
2. Peristalsis
Cells of intestinal glands:
1) Digests and absorbs nutrients
2) Secretes mucous
3) Secretes: secretin, cholecystokinin, gastric inhibitory peptide
4) Regenerative cell
5) Secretes lysozyme, capable of phagocytosis
1) Absorptive cell
2) Goblet cell
3) Enteroendocrine
4) No name on slide
5) Paneth cells
Histology of large intestine:
1) Muscular layer – ?
2) ____ – visceral peritoneum
3) ____ – contains large amounts of lymphatic tissue
1) internal circular layer is normal; outer longitudinal muscle: taeniae coli, haustra (pouches) formed, epiploic appendages (growths from taeniae coli)
2) Serosa
3) Appendix
What are six main functions of the liver? Hint:
1) sugar
2) LDL, HDL, VLDL
3) albumin, alpha beta globulins, plasma enzymes, glycoproteins, prothrombin
4) ETOH & barbiturates degraded by oxidation hydroxylation
5) RBC waste product billirubin secreted in bile
6) bile synthesized - emulsifies fat in intestines
1) Glucose regulation
2) regulation of blood lipid levels Lipoprotein synthesis
3) Synthesis of plasma proteins
4) Detoxification
5) Excretion (blood filtering). RBC is phagocytosed by Kupffer cells.
6) Exocrine secretion
Describe how the liver regulates glucose
When glucose enters the blood stream, insulin is released from the pancreas initiating glycogenesis to create glycogen which is stored in liver. If there is too little glucose then the pancreas produces glucagon. Glucagon (along with epinephrine) initiate glycogenolysis to produce more glucose from liver storages
Pancreatic secretions:
1) Endo + Exo (70%)
2) DNAse, RNAse
3) Hydrolyse starch and glycogen
4) triglycerides -> fatty acids and glycerol
1) Endopeptides - trypsin, chymotrypsin, elastases
Exopeptidases - carboxypeptidases
trypsinogen-> enterkinase (duct walls) -> trypsin -> activates all other precursors
2) nucleases
3) pancreatic amylase
4) pancreatic lipase
Regulation of pancreatic secretion (1 of 4):
1) ___: food -> release of stomach acid into duodenum -> release of ___ into blood by duodenal cells -> secretion of bicarbonate by ____ cells -> alkaline pH (ideal for pancreatic enzymes)
1) Secretin; Secretin; Duct cells
Regulation of pancreatic secretion (2 of 4):
2)___/cholecystokinen: amino acids and fats in intestine -> release of _____ by intestinal mucosa into blood -> release of pancreatic enzymes into intestine
2) Pancreozymin; pancreozymin
Regulation of pancreatic secretion (3 of 4):
3) ___: food -> __ secretion by stomach mucosa -> release of pancreatic enzymes into intestine
3) gastrin; gastrin
Regulation of pancreatic secretion (4 of 4):
4) ___ = Vagus nerve
4) Autonomic innervation
Respiratory epithelium:
1) ___ ciliated __ epithelium nasal cavity to bronchi
2) ___ - filled in their apical portions with granules of mucin glycoproteins.
* The lamina propria of resp. epthel. is vascularized
1) Pseudostratified ciliated columnar epithelium
2) Mucus-secreting goblet cells
The olfactory chemoreceptors are located in the ____, a specialized region of the mucous membrane covering the superior ___ at the roof of the nasal cavity.
1) olfactory epithelium
2) conchae
The olfactory epithelium is a pseudostratified columnar epithelium composed of what three parts?
1) Basal, stem cells
2) Supporting cells
3) Receptor cells (Neurons)
Internal nares are also called
Conchae
What are the three regions to the pharynx?
Nasopharynx, oropharynx, laryngopharynx
Nasopharynx lies over soft palate. Starts at the ___. Contains the pharyngeal tonsils, ___. *Lined with ____ epithelia. Openings to two ___ (auditory or Eustachian) tubes which help with three things:
1) internal nares
2) adenoids
3) respiratory
4) pharyngotympanic
5) open into middle ear, open by swallowing or yawning, help equalize air pressure on the ear drum
____ is a fleshy extension at the back of the soft palate which hangs above the throat.
uvula
The pharynx is a tube with walls of ___ muscle and lined with mucous membrane.
skeletal
Oropharynx extends from soft palate down to level of ____ bone. Receives the ____ (opening from oral cavity) contains two types of tonsils (____ tissue):
1) ____ (ones removed during tonsillectomy)
2) ____ tonsils (lie at base of tongue)
A) hyoid B) fauces C) lymphoid 1) palatine 2) lingual
A circular ring of lymphoid tissue that guards the entrance to the nasopharynx and oropharynx
The ‘tonsilar’ Waldeyer ring
Laryngopharynx extends downward from level of hyoid bone*, empties into:
1) ____(food tube) posteriorly
2) larynx (voice box) and trachea anteriorly
1) esophagus - opening = upper esophageal sphincter
2) larynx - opening = glottis
The ___, in addition to maintaining an open airway, movements of laryngeal cartilages by skeletal muscles participate in sound production during ____, and the _____ serves as a valve to prevent swallowed food or fluid from entering the trachea
1) larynx
2) phonation
3) epiglottis
The larynx contains ___ and ___ cartilage
Thyroid cartilage and cricoid cartilage
The ____ projects from the upper rim of the larynx and extends into the pharynx.
epiglottis
The wall of the trachea is lined by typical _____ underlain by lamina propria and _____ in the lamina propria and submucosa.
Submucosa contains C-shaped rings of hyaline cartilage covered by ____ .
The watery mucous fluid produced by goblet cells and by the glands forms a layer permitting ciliary movement to propel foreign particles out of the respiratory system in the ____.
1) respiratory epithelium
2) seromucous glands
3) perichondrium
4) mucociliary escalator.
From the bronchial tubes to the lungs, ___ decreases and ___ increases
cartilage decreases and smooth muscle increases
Each broncho-pulmonary segments is supplied by a different _____ bronchus.
tertiary (segmental)
How do cells change descending from larger bronchioles to smaller ones?
In the larger bronchioles, the epithelium is still ciliated pseudostratified columnar, but this decreases in height and complexity to become ciliated simple columnar or cuboidal epithelium in the smaller terminal bronchioles.
Descending from larger bronchioles to smaller ones, ____ cells disappear during this transition, but the epithelium of terminal bronchioles instead contains other numerous columnar cells, commonly called ___ cells which are mitotically active cells secrete ____ components and have various important defensive roles.
1) Goblet
2) Club
3) Surfactant
In bronchioles there is a lack of cartilage and ___
glands
Groups of cells, called ____ bodies, occur in some bronchioles and at higher levels in the bronchial tree.
These are innervated by autonomic and sensory fibers and some of the cells appear to function as ____ receptors in monitoring air O2 levels.
Terminal bronchioles branch into ____ bronchioles.
1) neuroepithelial
2) chemosensory
3) respiratory
*Epithelial stem cells are also present in these groups of cells.
Portions of the respiratory bronchioles are lined with ciliated ____ epithelial cells and ___ cells.
At the rim of the alveolar openings, the bronchiolar epithelium becomes continuous with the squamous alveolar lining cells (______).
Proceeding distally along these bronchioles, the alveoli increase in number, and the distance between them is reduced.
1) Cuboidal
2) Club
3) type I alveolar cells/type 1 pneumocytes
Which muscle and tissue type lie beneath the epithelium of respiratory bronchioles?
Smooth muscle and elastic connective tissue
Type I alveolar cells (also called ___) are extremely thin cells that line the alveolar surfaces and cover __% of the alveolar surface.
Organelles such as the ER, Golgi apparatus, and mitochondria are grouped around the ___, leaving large areas of cytoplasm free of organelles and reducing thickness of the ___ for gas exchange.
1) type I pneumocytes or squamous alveolar cells
2) 97% = type 1; (type II cells covering the remainder).
3) nucleus
4) blood-air barrier
What is emphysema?
When alveoli burst and fuse into enlarge air spaces. surface area for gas exchange is reduced
In the blood- air barrier, respiratory gases have to diffuse across which 3 layers?
1) alveolar epithelial cell
2) basement membrane
3) capillary endothelial cell
Type II alveolar cells (___) are interspersed among the type I alveolar cells.
Type II cells are ___ cells that often occur in groups of two or three along the alveolar surface at points where the alveolar walls unite.
- type II pneumocytes
2. cuboidal
Type II alveolar cells divide by ___ to replace their own population and provide ____ to replace the type I population.
- mitosis
2. progenitors
