PRACTICAL 2 FINAL

What two main groups can the digestive system be broken into?

1) The alimentary canal

2) The accessory digestive organs

What is another name for the alimentary canal?

gastrointestinal tract / GI tract

One long muscular, hollow tube that extends from the mouth to the anus (includes mouth, oropharynx, esophagus, stomach, and small & large intestines

Alimentary canal (aka gastrointestinal / GI tract)

What are the accessory digestive organs?

1) teeth

2) tongue

3) gallbladder

4) salivary glands

5) liver

6) pancreas

5 main processes of digestion

1) ingestion

2) propulsion

3) mechanical & enzymatic digestion

4) absorption

5) elimination

Where do mechanical and enzymatic digestion each begin?

They both begin in the mouth

What two important enzymes are produced in/with saliva by the salivary glands?

1) Amylase

2) Salivary lipase

What macromolecule does amylase metabolize?

carbohydrates

The appendix is described as a “______” organ in humans

vestigial

What is different about the appendix when comparing humans to cats?

Humans- vestigial organ

Cats- discarded via evolution (same for many animals)

What is different about the respiratory structures of the human vs. the cat?

Human: Due to cardiac notch…(1) Left primary bronchus is longer, (2) Left lung is smaller

-Left lung smaller because the heart has to fit, and fits into the cardiac notch

-Left primary bronchus is longer, because it has to pass under aorta and across esosphagus to reach left lung

(none of this is true for felines, as there are quadrupeds, so their thoracic cavity is shaped differently than that of a bipedal human.)

thin, oily, substance; surface-active lipoprotein complex formed by type II alveloar cells- reduces surface tension

Pulmonary surfactant

Surfactant in the lungs acts to reduce _________

surface tension

Pulmonary surfactant is formed by …

type II alveolar cells

Explain why pulmonary surfactant is important / the 2 things that happen pulmonary surfactant prevents…

Pulmonary surfactant is important because…

-reduces surface tension at the air-to-liquid interface in the alveoli

1) It decreases surface tension, preventing the alveoli from collapsing / making it easier to breathe

2) It decreases surface tension, helping prevent fluid from being drawn into the alveoli, keeping the airways dry / keeping fluid from accumulating

(Pulmonary surfactant is a thin, oily substance composed mainly of phospholipids and produced by type II alveolar cells. Its main function is to decrease surface tension at the air–water interface inside the alveoli. Because water molecules form hydrogen bonds and exhibit cohesive properties, they create surface tension that pulls the alveolar walls inward and can lead to alveolar collapse. The increased surface tension can also contribute to pressure differences that promote fluid movement into the alveoli. By reducing surface tension, pulmonary surfactant helps prevent alveolar collapse and helps keep the alveoli open for efficient gas exchange.)

GO BACK AND ADD THE STUFF FROM THE SLIDES / THE NOTES I TOOK ON PAGE 104 for LAB 6

…

Technique we did in lab for recording respiratory varibales (measures how much air and how quickly you can inhale & exhale air)

Spirometry

Primary function of the Respiratory system….

1) To release carbon dioxide from the body

2) aquire oxygen for use by the body

Four steps of Respiration…..

1) pulmonary ventilation

2) external respiration

3) transport of respiratory gases

4) internal respiration

The movement of air into the lungs

inspiration

The movement of air out of the lungs

expiration

What is the term for the movement of air into (inspiration) and out of (expiration) the lungs so that the gases in the lung are constantly refreshed with infustions of new air and effusion of old air

Pulmonary ventilation

During __________ carbon dioxide diffuses to the lungs from the blood, and oxygen diffuses to the blood from the lungs

external respiration

______________ is accomplished using the blood of the cardiovascular system. Carbon dioxide is transported from the cells of body tissues to the lungs, and oxygen is transported from the lungs to the cells of body tissues.

Transport of respiratory gases

_________ occurs as oxygen diffuses form blood to the cells of the body, and carbon dioxide diffuses from the cells of the body to the blood

Internal respiration

(this is more a function of the blood / cardiovascular system)

Carbon dioxide is produced and oxygen is used, by cells, for energy production during __________

cellular respiration (in oxidative reactions).

Upper respiratory system vs Lower respiratory system (with what structure do they start and end?)

Upper respiratory system: Structures from the nose to the larynx

Lower respiratory system: The larynx and the structures inferior to is

The ____ warms and moistens entering air, provides a resonating chamber for vocalizations, cleans and filters entering air, and houses the olfactory receptors.

Nose

4 functions of the nose…

1) Warms and moistens entering air

2) Provides a resonating chamber for vocalizations

3) Cleans and filters entering air

4) Houses the olfactory receptors

What accounts for the different nose shapes people have?

The differences in nasal cartilages (the ones that form parts for the nose are pretty consistent in regards to the external appearance they facilitate)

2 types of mucosa in the nasal cavity

1) Olfactory mucosa

2) Respiratory mucosa

A small portion of the superior nasal cavity is line with ______________ containing receptors for smell. The rest of the nasal cavity is lined with respiratory mucosa composed of ________________ with goblet cells and seromucous nasal glands

olfactory mucosa epithelium ; pseudostratified ciliated columnar epithelium

Composed of cells that secrete mucus (traps bacteria, dust, and debris) and cells that secrete a watery (to humidify incoming air), enzyme rich (contains lysozyme which is antibacterial) fluid

Seromucous nasal glands

What do seromucous nasal glands’ function?

1) Composed of cells that secrete mucus (traps bacteria, dust, and debris)

2) Composed of cells that secrete a watery (to humidify incoming air), enzyme rich (contains lysozyme which is antibacterial) fluid

What do respiratory mucosa epithelial cells secrete to assist in killing microbial invaders?

antibiotic defensins

What is triggered when irritants (dust, pollen, etc.) contact the rich supply of sensory nerve endings in the nasal cavity?

Sneeze reflex

How is cold air warmed by the nose?

Thin walled veins and plexuses of capillaries lie just beneath the nasal epithelium and warm the air as it is inspired…

When cold air stimulates plexuses beneath the nasal epithelium when inspiring, what happens to the plexuses?

They engorge with blood, allowing for greater heat transfer

What is the reason nosebleeds are so easy to get?

Blood vessels in the nose are very superficial, and this exposes them to damage

Role of the nasal conchae

-Increase surface area

-Help create turbulence, which deflects non-gaseous particles onto the mucus coatings

The _________ increase surface area in the nose and Help create turbulence, which deflects non-gaseous particles onto the mucus coatings

Nasal conchae

Explain how the heat and moisture gradient in the nose is constantly flipping as we breath

1) Inspired air is warmed as we breathe in

-in the process, the conchae are cooled (since they are the ones giving away warmth to the incoming air)….

2) Upon expiration, the cooled conchae cause moisture to precipitate out… and heat to be exchanged into the conchae to warm them

__________ are located in the frontal, sphenoid, maxillary, and ethmoid bones.

Paranasal sinuses

Role of paranasal sinuses

lighten the skull

Paranasal sinuses lighten the skull, but they are prone to ________

Inflammation, especially due to infection or allergies

Term for inflamed sinuses

Sinusitis

Why does inflamed sinuses cause pain associated with sinus headache?

When the sinuses are inflamed (sinusitis), additional mucus (and inflammatory products) are produced and can block the openings between the sinuses and the nasal cavity. When this happens, the air in the sinus is absorbed and a partial vacuum is created, which causes the pain.

What happens with inflammation of the nasal mucosa?

Excessive mucus production leading to congestion and postnasal drip

When swallowing food, the muscular ___________ and ________ move superiorily to block off the ________, and the __________ flaps over the _______, to keep food out of the nasal cavity and lungs, respectively

When swallowing food, the muscular _____soft palate______ and ____uvula____ move superiorily to block off the ____nasopharynx____, and the _____epiglottis_____ flaps over the ___larynx____, to keep food out of the nasal cavity and lungs, respectively

In the nasopharynx, ______ propel mucus toward the stomach

Cilia

Common name is the adenoids, but their real name is the __________

Pharyngeal tonsils (of the nasopharynx)

The pharyngeal tonsil (adenoid) of the nasopharynx contains _________ tissue that traps and destroys pathogens.

Lymphatic

The __________ of the nasopharynx contains lymphatic tissue that traps and destroys pathogens.

pharyngeal tonsil (adenoid)

The _______________ connect the middle ear to the nasopharynx so that air in the middle ear can match pressure with atmospheric air which is important for sound conduction and proper hearing

pharyngotympanic tubes

Role of the pharyngotympanic tubes

-Connect the middle ear to the nasopharynx… so that air in the middle ear can match pressure with atmospheric air

The __________ and _________ receive both food and air and thus have a more protective stratified squamous epithelium.

Oropharynx and laryngopharynx

The oropharynx transitions directly into the ___________

Laryngopharynx

Two zones of the respiratory system

respiratory zone & conducting zone

What makes up the respiratory zone & what makes up the conducting zone?

respiratory zone- site of external respiration (where gas is exchanged)… made up of microscopic alveoli, alveolar ducts, and respiratory bronchioles

conducting zone- consists of all the tubes transporting air from the nose to the respiratory bronchioles (during this process, air is humidified, warmed, and filtered/cleansed)

Another name for the vocal cords

vocal folds

Where are the vocal folds?

In the larynx

Function of the vocal folds

voice production

What is the real name for the Adam’s apple?

The laryngeal prominence of the thyroid cartilage

Why is the laryngeal prominence more prominent in males than females?

1) The thyroid cartilage is stimulated by androgens during male puberty grow larger

2) Also, estrogens stimulate fat deposition in the necks of females that obscure their smaller laryngeal prominence

What anchors the vocal cords?

The arytenoid cartilages

When you are unconscious…….. anything other than air entering the larnyx leads to…..

a cough reflex to expel it- this is why liquids should never be given orally to a patient who is unconcious.

The vocal folds and the opening between them are collectively called the _______

glottis

Below the vocal folds, into the larynx and trachea, the epithelium changes back to ___________________ epithelium

pseudostratified ciliated columnar epithelium

Which way does the pseudostratified cilitated columnar epithelium sweep mucus and why?

It sweeps the mucus up toward the pharynx so that it can be swallowed.

The glottis opens and closes during intermittent expiration to produce ________.

speech

-The glottis (the space between the vocal folds) opening and closing during intermittent expiration to produce speech means that vocal folds vibrate to break the steady airflow from the lungs into small, rapid pulses of air. This process, known as phonation, converts air pressure into sound, which is then shaped by the throat, mouth, and nasal cavity into speech.

The laryngeal muscles move the cartilages of the larynx (mostly the arytenoid) to change the length of the vocal folds and size of the glottis to ……

change the pitch and produce vocalization

How do the laryngeal muscles work to change the pitch and produce vocalization?

The laryngeal muscles move the cartilages of the larynx (mostly the arytenoid) to change the length of the vocal folds and size of the glottis

Tense vocal folds will vibrate more to produce…

higher pitch

What happens to thyroid cartilage and other structures during male puberty, and what does this lead to?

The thyroid cartilage is enlarging, and the rest of the larynx, including the vocal folds (which become longer and thicker), also enlarge to produce a deeper voice

Loudness is determined by what…

the force with which the air is expired across the vocal folds (more force equates to louder sound)

What do the pharynx, nasal, oral, and sinus cavities do to sound?

They resonate sound to enhance and amplify it.

How does enunciation happen?

Muscles in the lips, soft palate, tongue, and pharynx fine tune the sounds as the waves escape us

_________ is imflammation of the vocal folds causing them to swell and vibrate incorrectly

Laryngitis

-This results in a hoarse tone, and is most commonly caused by viral infection.

Laryngitis is most commonly caused by __________

A viral infection

When straining to defecate, what can happen to the vocal folds / other body structures and why?

The vocal folds can completely close over the glottis to stop air passage…. in this case, the abdominal muscles contract, and the glottis closes, to increase intra-abdomincal pressure to help empty the rectum

Under certain conditions, the vocal folds can completeluy clsoe over the glottis to stop air passage, such as when straining to defecate. In this case, the abdominal muscles contract, and the glottis closes, to increase the intra-abdominal pressure to help empty the rectum. This is known as …….

The Valsalva maneuver

How does the Valsalva maneuver slow the heart rate? (2 ways)

Increases the pressure in the thorax, which ….

1) decreases venous return to the heart by squeezing on the major blood vessels

2) Presses on the vagus nerve to increase vagal tone

At a constant temperature, the pressure of a gas varies inversely with its volume…. this is known as…..

Boyle’s Law

Inspiration is alway an _______ process

Active! This is because you using energy / are always contracting at least one muscle to do it

How does the body use Boyle’s law to breath?

In order to exhale air, we squeeze on the thorax and decrease the volume by relaxing (expiration is largely passive in normal breathing due to recoil of the pulmonary structures) the diaphragm (relaxed domes up into the thorax) and external intercostal muscles (relaxed allows ribs and sternum to depress and ratchet down) to increase pressure in the thorax until the intra-thorax pressure exceeds atmospheric pressure which then forces air out of the lungs.

How does forced expiration work?

A forced deep expiration is accomplished by contracting the abdominal wall muscles which pushes the abdominal organs somewhat superiorly against the thorax, and the rib cage is pull inferiorly to further increase pressure in the thorax.

Additionally, the internal intercostal muscles also depress the rib cage to further increase pressure for forced expiration

What are all the muscles of expiration?

Internal intercostals, Rectus abdominis, External obliques, Transverse abdominis, Internal obliques, (Diaphragm)

What are all the muscles of inspiration?

External intercostals, Scalenes, Sternocleidomastoid, Diaphragm

Heart rate _______ when we breathe in and _________ when we breath out

Heart rate increases when we breathe in and decreases when we breath out

The trachea, similar to other tube structures of the body, such as the gastrointestinal tract, is composed of a (1)___________, (with pseudostratified columnar ciliated epithelium containing goblet cells which produces and moves mucus up and out of lungs), a (2) ________ (with seromucous glands), and (3) _________ (outermost connective tissue sheath)

(1) Mucosa

(2) Submucosa

(3) Adventitia

What holds the trachea open?

C-shaped cartilage rings

What shape is the cartilage rings in the trachea, and why are they that shape?

They are C-shaped, so that the esophagus behind can expand during swallowing

Why is it important that respiratory structures remain open at all times?

If they opened and collapsed consttatnly, then great amounts of energy would be needed to overcome the cohesive and adhesive properties of wet structures in contact with one another in order to open them when bringing in air.

The ____________ lies between the esophgus and trachea and contraction of the this aids in the rapid movement of air and mucus out of the lungs and trachea during coughing

trachealis muscle

Each lobe of the lung is fed by one ____________.

Seondary (lobar) bronchus ; (3 lobes on the right, 2 lobes on the left)

Passageways in the lung where the branching produces diameters smaller than 1mm are termed __________

bronchioles

Do the bronchioles contain cartilage?

No

As the conducting tubes of the lungs beocmes smaller, the mucosal epithelium thins until ultimately becoming ________ epilelium in the terminal bronchioles with very few cilia and mucus producing cells.

cuboidal

As the tube walls of the lings decrease in diameter, the percentage composition of smooth muscle in the walls __________

increases - this allows for constriction and dilation to control the restriction and dilation to control the resistance to air passage to meet out physiological demands (such as dilation during exercise to increase gas exchange capabilities)

An ___________ is basically the cluster of alveoli coming off an alveolar duct.

alveolar sac