Unit 5 Lectures Flashcards
What is the function of the respiratory system?
- Conduction of gases to and from lungs
- Protection of respiratory surfaces
- Sound production
- Defense against airborne pathogens
- Gas exchange (o2 coming in, co2 leaving)
- Regulation of blood volume, BP, pH, etc
What are the zones of the respiratory system?
Conduction zone and respiratory zone
What is the conduction zone?
This is the pathway that leads to the lungs
- transports air
- warms, humidifies, and filters air
- sound production
What is the respiratory zone?
This is the area inside of our lungs
- defense mechanisms
- gas exchange
- regulation of blood properties
What is the conductive zone tracing?
nose - nasal cavity - pharynx - larynx - trachea - bronchi - terminal bronchioles
What is the respiratory zone tracing?
Respiratory bronchioles - alveolar ducts - alveolar sacs - alveoli
What process occurs at the alveoli?
Gas exchange
What are the two components of gas exchange?
External respiratory and internal respiratory
What is the difference between external respiratory and internal respiratory?
External: lungs and blood stream
Internal: blood and oxygen starved tissues
Why is it important for our nasal cavity to have PSCC?
Because they have goblet cells that secrete mucus which filter debris
What is the overall function of the nasal cavity?
It consists of nasal conchae and ridges that swirl air and throw it against mucus to create sticky wall and filter debris. It is also highly vascular to warm the air
What are the 3 parts of the pharynx?
Nasopharynx
Oropharynx
Laryngopharynx
What areas does the nasopharynx cover?
hard palate to uvula
What areas does the oropharynx cover?
Fauces (end of soft palate) to the hyoid bone
What areas does the laryngopharynx cover?
hyoid bone to esophagus
Why is the oropharynx and laryngopharynx lined with stratigies squamous tissue?
Because this tissue protects them from abrasion
What is the difference between the fauces and the epiglottis?
Both are flaps found in our pharynx
Fauces: ensures food does not go from mouth to nose
Epiglottis: ensures food does not go to respiratory system
The pharynx is known as the ____ while the larynx is known as the ______
Pharynx: throat
Larynx: voicebox
What are the parts of the larynx?
Thyroid cartilage (largest in this region)
Laryngeal prominence (on thyroid cartilage)
Epiglottis
Cricoid Cartilage
What creates a guys adam’s apple?
Enlarged thyroid cartilage
What is the difference of vocal cords between women/ children and men
Women and children: vocal cords are thinner causing a higher pitched voice
Men: vocal cords become thicker after puberty, causing a deep voice
What are the parts of the trachea?
Carina (end of trachea, where it splits)
C-shaped cartilage rings
Trachealis muscle (posterior)
What is the difference between the right and left bronchus?
Right: wider and vertical
Left: narrow and horizontal
If you inhale something pastthe carina, which bronchi is it more likely to go into?
Right
What happens to lungs with asthma?
There is swelling of the tubes and an increase of mucus secretion
There are ____ to _____ million alveoli
300-500 million alveoli
Where does the majority of gas exchange occur?
Alveoli
What are the cells of the alveoli (inside the lung)?
Type 1 Cells
Dust cells
Type 2 cells
What are the functions of type 1 cells?
gas diffusion
What is the function of dust cells?
These cells hold alveolar macrophages that remove pathogen and debris from the lungs
What is the function of type 2 cells?
Produce surfactant, reduce surface tension, allow lungs to stay inflated
What is surfactant?
It is a fluid secreted by type 2 cells into the alveolar space to reduce surface tension and prevent the collapse of alveoli
What is respiratory distress syndrome?
Mainly occurs during fetal development. By about 7-8 months, surfactant should be produced. if an infant is born prematurely, they can have little or no surfactant and whenever they beathe, their alveoli will collapse
It can happen in adults but it means their lung is disease
What is emphysema?
Progressive disease, mainly common in long-term smokers or those who work around chemicals. It causes alveolar walls to be destroyed , constricts capillaries, and reduces surface area of gas exchange. The elastic fibers can also breakdown
Smokers who have been smoking for over 40 years have what condition?
Emphysema, 100% have it
Where are our lungs housed?
Pleural cavity
What are the pleural membranes?
Parietal (membrane that lines the cavity)
Visceral (membrane that lines the lungs)
Both secrete pleural fluid
What is the function of pleural fluid?
To seal the membranes together
What are the lobes of our right lung?
Superior lobe
Middle lobe
Inferior lobe
What are the lobes of our left lung?
Superior lobe
Inferior lobe
What are the 2 general categories of muscles we use?
Inspiration muscles and expiration muscles
What is inspiration? What muscles are found here?
Inspiration: inhaling
when inhaling we use the diaphragm and external intercostals
What is expiration?
Passive process and muscle relax
What controls breathing?
Since it is a reflux, it is controlled by the medulla oblongata and the pons
How does breathing work?
When we inhale, our external intercostals contract and the diaphragm moves down, our rib cage expands
When we exhale, muscles relax, diaphragm moves back up and elastic of lungs recoils
What happens to pressure when inhaling?
When you inhale, the throacic, pleural cavity volume and lung volume increases so pressure drops
How does the medulla oblongata and pons work with our heart to control breathing?
If they detect low amounts of co2 in the heart (through chemoreceptors), it will cause an increase rate of breathing so we can get more oxygen
What does nicotine do to our lungs?
It constricts terminal bronchioles
What does Carbon monoxide do to our lungs
binds to hemoglobin (the protein that carries oxygen to the body) so less oxygen is available for other organs
What does the irritants in smoke do to us?
- increases mucus production
- swells the tissue of respiratory tubules
- reduces the function and destroys cilia (hair like appendages that help move debris and substances out of the lungs)
What happens to long term smokers?
Their elastic fibers breakdown and their bronchioles collapse. They can also develop a form of emphysema
What are the general tunics of the digestive tract?
Tunica mucosa
Tunica submucosa
Tunica muscularis (circular and longitudinal)
Tunica externa (adventitia and serosa)
What does the tunica mucosa consist of?
It is the deepest layer (inside the stomach) and has a muscularis mucosa at the bottom
What does the tunica submucosa consist of?
veins, arteries, capillaries and the submucosal plexus
What does the tunica muscularis consist of?
two layers; circular and longitudinal, in between those there is a myenteric plexus
What tunics are in the stomach?
Tunica mucosa
Tunica submucosa
Tunica muscularis (circular, longitudinal, and oblique)
Tunica externa
What structures does the ilium have?
villi, peyer’s patch, intestinal glands
What structures does the duodenum have?
Duodenal glands
What is the function of our digestive system?
Ingestion Mechanical digestion Propulsion Chemical Digestion Absorption Defacation
What is the GI tract tracing?
oral cavity, pharynx, esophagus, stomach, small intestine (duodenum, jejunum, ilium), large intestine (ascending, transverse, descending, sigmoid), rectum, anus
What are mesenteries?
Connective tissue that connects our organs together and anchor them to our body
What are the mesenteries found in our abdominal region?
Falciform ligament, lesser omentum, greater omentum, mesentery proper, mesocolon
What is the falciform ligament?
Seperates liver into 2 (left and right) and attaches it to the anterior abdominal wall
What is the lesser omentum?
It connects the stomach from the liver
What is the greater omentum?
Comes down from stomac and lays like a fat apron over the small intestines
What is the mesentery proper?
It attaches the small intestines to the back wall of the abdominal cavity
What is the mesocolon?
It attaches the large intestine to the back wall of the abdominal cavity
What digestive organs are part of the retroperotineal space?
ascending and descending colon
Rectum
Pancreas
Duodenum
What mouth strucutre helps guide food down the pharynx?
The uvula
what is enamel?
The hard white covering of the teeth
What is the difference between peristalsis and swallowing?
Swallowing: can be voluntary or involuntary
Peristalsis: muscular contraction waves that move the food through GI tract
Is the esophagus controlled by swallowing or peristalsis ?
Peristalsis
What sphincter is at our esophagus?
Cardiac sphincter: pretty weak, can cause our stomach acid to move up and create acid reflux
What is the main function of the stomach?
Very acidic and functions to breakdown proteins into amino acids
What substance does our stomach use to breakdown proteins?
HCl which gives it a pH of 2-3
What are the 2 types of cells in the stomach?
Chief and Parietal
What are chief cells?
Cells that secrete pepsinogen (a precursor to pepsin)
What are parietal cells?
They make HCl
What is pepsin?
An enzyme that is responsible for breaking down protein
What organ secretes pepsin?
Gastric glands
What property MUST the stomach have in order to prevent self destruction?
In order to prevent self-destruction from acidic conditions, the stomach must have large amounts of mucus
Why is it important for the stomach to have 3 muscle layers (tunica muscularis)?
Because it allows it to contract and digest food through segmentation
What sphincter is found at the stomach?
At the end of the stomach, we have a pyloric sphincter (strong) and it helps pass food to small intestine
What substances can the stomach absorb?
water, electrolytes, some drugs (aspirin) and alcohol
What enzyme is secreted by the stomach to break down alcohol? why?
Alcohol dehydrogenase to make it less toxic
What are the 3 parts of the small intestine?
Dudoenum, Jejunum, and Ilium
What small intestine segment has secretions from pancreas and liver?
Duodenum
What substances does the duodenum breakdown?
Carbohydrates, lipids, and proteins
What are submucosal glands?
These are glands found in the duodenum that secrete bicarbonate to neutralize the acidity
Which small intestine area has the most amount of absorption? Why?
The jejunum, it has enlarge villi and plicae
What is the last segment of the small intestine that takes food to the large intestine?
Ilium, specifically the ileocecal valve
What is the difference plicae, villi, and microvilli?
Plicae: ridges in the inner surface of intestine
Villi: finger-like projections that have lacteal to absorb fats and capillaries for non-lipid nutrients
Microvilli: Are found on the cells that make up the villi and they create a brushed border
What is the primary function of the large intestine?
absorb water, vitamins, compaction, and defacation
What are the accessory structures of the large intestine?
Appendix, taneia coli, colon, haustra
What gland is found in the oral cavity? what does it secrete? what does the secretion break down?
Salivary glands, they secrete salivary amylase and they breakdown carbohydrates
What cells are found in the stomach? What does it secrete? what does the secretion break down?
Parietal and chief cells secrete HCl and Pepsinogen which combined make pepsin. This secretion break down proteins