Lecture 20 4/15/14 Flashcards
Respiratory Centers of the brain
located in the reticular formation of the pons and medulla.
Respiratory Rhythmicity Centers
Sets the basic rhythm for respiration. Not thinking about respiration. Controls the Respiratory Rate and Rhythm at Rest.
Two Parts of the Respiratory Rhythmicity Centers
Dorsal Respiratory Center
Ventral Respiratory Center
Dorsal Respiratory Center
Controls the Respiratory, Rate, and Rhythm Centers.
Ventral Respiratory Center
Anterior to dorsal. Involved in the spill over effect into the ventral during exercise. Increase the respiratory rate.
Apneustic Center
located posterior and inferior to pons. Blocks off or switches off the inspiratory ramp. Adjust the rate and depth of respiration.
Pneumotaxic Center
Involved modifying the activities of the rhythmicity center.
Mechanoreceptors
Respond to lung volume
Mechanoreceptors Proper
Stretch receptors of the lung
Inflation Reflex
Prevents over expansion of the lungs
Deflation Reflex
Opposite of Inflation Reflex. Stimulates inspiration when the lungs begin to collapse.
Baroreceptors
Monitors blood pressure through the lungs
Chemoreceptors
They monitor blood gases and pH.
CO2, O2, and pH.
CO2 is the main driver for what?
Respiration
Increase in CO2 causes what?
Drives respiration.
In high altitudes, what drives respiration?
O2
Higher Centers in the brain?
Cerebrum which allows voluntary control of respiration
Receptors from these areas send info back to the brain to alter respiration. What are they?
Mechanoreceptors
Chemoreceptors
Higher Centers in the Brain
Respiratory Center performance can be altered by what?
Input from:
Mechanoreceptors
Chemoreceptors
Higher Centers in the Brain
Digestion
the process of converting food to chemical substances that can be absorbed and assimilated by the body’s tissues.
5 Activities of Digestive System
Ingestion
Peristalsis
Mechanical and Chemical Digestion
Absorption
Defecation
Ingestion
eating/taking food into the body
Peristalsis
the movement of food along digestive tract via smooth muscle contraction. Pushes food into one area to the next.
Mechanical and Chemical Digestion are a part of what?
part of the mouth
Mechanical Digestion
starts in the mouth. Physical movement, moving the tongue around to mix the saliva with the food we chewed in the mouth.
Chemical Digestion
food gets to the stomach. Churning of food, chewing to mix with digestive enzymes. Anything involved in breaking down food molecules into smaller food molecules. Enzymatic reactions that break down carbohydrates, lipids, and proteins into usable molecules.
Absorption
the passage of digested materials into the circulatory system and lymphatics.
Defecation
When this material that we’re digesting moves through the stomach and the small and large intestine, it is a semi liquid material in the small intestine, but in the large intestine, it pulls the water out of the material, so then the semi liquid turns to a semi solid material and then we defecate that material.
The elimination of digestive waste products.
Gastrointestinal Tract - AKA Alimentary Canal
a continuous muscular tube that runs through the ventral body cavity extending from mouth to the anus. Approximately 30 feet long.
What are the Organs of the Digestive Tract
1) mouth
2) pharynx
3) esophagus
4) stomach
5) small intestine
6) large intestine
Accessory Organs are involved with what?
Assisting Digestion
What are the Accessory Organs
1) teeth
2) tongue
3) salivary glands
4) gastric and intestinal glands
5) liver
6) gall bladder
7) pancreas
8) spleen
What are the four layers of the GI Tract
Tunica Mucosa
Tunica Submucosa
Tunica Muscularis
Tunica Serosa
Tunica Mucosa Has 3 Layers
Epithelium
Lamina Propria
Muscularis Mucosa
Epithelium of Tunica Mucosa
Inner most layer. Lines lumen of GI Tract, mostly simple columnar epithelium for absorption.
One cell layer thick that promotes absorption. Oral cavity, pharynx, esophagus, and anus is stratified squamous epithelium and then it transitions almost to immediately to a simple columnar epithelium that we would see in the stomach and small and large intestines. Protection.
Lamina Propria of Tunica Mucosa
its loose connective tissue, not dense connective tissues. 80% diffusable with water. Highly diffusable. Deep to epithelium. Has blood and lymph vessels.
Muscularis Mucosa of Tunica Mucosa
serves two purposes, helps to throw those inner hypothelium into folds that we call, vili, finger like projections that increase surface area for greater absorption. And the other things that it does is that , it regulates blood vessel flow through the lamina propria and Meissners Plexus. Deep to lamina propria, smooth muscle layer that throws the mucous into folds, serving to increase the surface area for absorption.
Meissners Plexus
known as submucosal plexus. Autonomic Nervous Plexus. Helps to control the muscularis mucosa, and then also involved in controlling vasodilation and constriction of those vessels, or blood flow in the vessels of the lamina propria.
Tunica Submucosa
where the Meissners Plexus is found. 2nd main layer, more of loose CT that binds tunica mucosa to next layer, contains blood vessels.
Tunica Muscularis
located throughout GI Tract. Involuntary smooth muscle
Two Layers of the Tunica Muscularis
Circular Fibers
Longitudinal Fibers
Circular Fibers
Inner Ring
Longitudinal Fibers
Outer ring
Auerbach Plexus
Nerve supply for the Tunica Muscularis.
Autonomic Nervous System for the GI Tract.
Tunica Serosa
Outermost layer.
Serrous membrane made of connective tissue and epithelium. AKA Visceral Peritoneum.
Peritoneum Membranes
Largest serrous membranes in the body
Function of the Peritoneum Membranes
Suspend and hold organs in place and reduce friction
Two Layers of the Peritoneum Membranes
Parietal Peritoneum
Visceral Peritoneum
Parietal Peritoneum
Lines inner abdominal wall
Visceral Peritoneum
Lines organs surfaces, makes up serosa
Embryological Development
fist and balloon theory. Abdominal organs invaginate into the peritoneum like fist in balloon.
Falciform Ligament
Connects liver to the diaphragm
Lesser Omentum
Connects Liver and stomach
Greater Omentum
Visceral fat, subcutaneous fat
Transverse Colon
connected to the back wall via the transverse mesocolon
Small Intestine cross sections and large intestine get thrown into what?
The mesenteries
Boundaries of the Oral Cavity
Lateral Walls
Anterior Walls
Superior
Inferior
Lateral Walls
Cheeks, muscular wall lined with
Anterior Walls
Lips, outside skin
Inside mucous membrane that transitions between inside and outside mucous membranes
Vermillon of Anterior Walls
Transitional zone between inner and outer lips
Superior Boundary of Oral Cavity
Hard Palate anterior 2/3
Soft Palate posterior 1/3
Inferior Boundary of Oral Cavity
Tongue and associate muscles of mouth floor
Posterior Fauces
opening between oral cavity and throat
2 Arches of the Palantine Arches
Palatoglossal arch
Palatopharyngeal arch
Palatoglossal arch
front one towards the tongue;
Anterior;
Uvula
Palatoglossal arch
back one;
Posterior
Tongue Of Oral Cavity
comprised of skeletal muscle covered with mucous membrane, has a tremendous amount of nervous innervation. Has a lot of dexterity to it. Involved in digestive process.
Muscle Types of Tongue
Extrinsic Muscle
Intrinsic Muscle
Extrinsic Muscle
originates outside of the tongue and inserts into the tongue
Intrinsic Muscle
originates inside of the tongue and inserts inside into the tongue
Lingual Frenulum of Tongue
a fold of mucous membrane on the midline under surface of the tongue
Lingual Frenulum Duct
Submandibular Ducts which open on either side of the lingual frenulum
Papillae of the Tongue
projections of the lamina propria covered with epithelium that line the tongue’s surface.
3 Types of Papillae
Circumvallate
Fungiform
Filiform
Circumvallate
form an inverted V, large, conical shapes, have bitter taste buds to help prevent us from eating poisonous material.
Fungiform
mushroom shaped more numerous at the tip. Located all over the tongue.
They are located on the sides because they are not exposed to direct abrasions.
Also they are in the recesses then there’s more fluid there for better diffusion of the chemicals that we pick up as taste. Red dots.
Filiform
slender projections, anterior 2/3 of the tongue. Thread like or shape.
Salivary Glands
glandular tissue that secretes saliva. Big guns. Don’t secrete much saliva. Only time it will is when you think about it or while you’re eating.
Saliva
keeps mouth moist, lubricates food, breaks down starches.
3 Pairs of Salivary Glands
Parotid Glands
Submandibular Glands
Sublingual Glands
Parotid Glands
The big guns. They don’t secrete much saliva normally. Only time it will is when you think about it or while you’re eating. Anterior and inferior to ear.
Parotid Duct or Stensons Duct is paired with Parotid Gland
Parotid Duct (Stensons Duct)
opens into oral cavity. Goes forward and then dives medially at the masseter and then enters at the upper second molar.
Submandibular Glands
Located beneath the base of the tongue.
Whartons Duct is paired with Submandibular Gland
Whartons Duct
Enter oral cavity on either side of lingual frenulum. Produces most of the saliva while we are resting.
Sublingual Gland
Located anterior underneath the tongue. 20-30 little ducts that go in. Multiple ducts enter into the floor of oral cavity. Provide less than 1% of saliva.
Groovenous Duct is paired with Sublingual Gland
Saliva Function
Initiates carb breakdown
Destroys bacteria
Lubricate food for swallowing
Composition of Saliva
Salivary Amylase
Mucin
Lysozyme
Teeth
Adults have 32 teeth and babies have 20 teeth. Total of 52 that we go through in our lifetime.
Function of Teeth
To aid in mechanical digestion
Crown
What sticks up above
Enamel
Hardest substance in human body
Dentin
resembles bone
Pulp Cavity
filled with vessels, nerves, and lymphatics
Root Canal
tooth is about to die, turns grey and stays intact, the ligaments look good then they would put a crown
Cementum
bone like attaches dentin to
Periodontal Ligament
Dense fibrous connective tissue. Attaches cementum to surrounding bone. Allows for some flexibility.
Neck
joins crown to root. Where the gum line is.
Root
Consists of 1-3 projections embedded in bone.
Adult Teeth have 4 Quadrants
1) Central or Lateral Incisors.
2) Cuspid Tooth or Canine Tooth.
3) Then Pre-Molars or bicuspid - cutting and tearing together and moving it to molars.
4) 1st, 2nd, and 3rd Molars. The 3rd molar is the wisdom tooth.
