Respiratory System

Module 5

What are the turbinates (or conchae) and what functions do they serve

Bony ridges in the nasal cavity (turbinates) covered with well vascularized tissue 

that warm and humidify the air before it enters the lungs. 

2. What is the function of the cartilage rings in the trachea?

They help to keep the trachea open. 

Why are the tracheal "rings" actually horseshoe shaped?

The esophagus is behind the trachea and the horseshoe shape allows the 

esophagus to expand without bumping into a hard surface. 

2. What are the muscles between the ribs and what is their function?

Intercostal muscles between the ribs help to elevate the ribs, bringing air to the lungs.

What is the function of the ribs sloping down at an angle?

When the ribs that are sloping downward elevate, it creates more space for air to enter the lungs, both front to back and laterally. 

How many lobes does the left lung have and how many lobes does the right lung have?

Right lung has three lobes; the left lung has two lobes. 

What important organ resides in the mediastinum between the lungs?

 Heart 

Why is it important that the lungs reside in a double wall pleural sac?

The lungs move as we breathe so the lubricant between the parietal and visceral layers of the pleural sac helps to keep the lungs from creating too much friction and heat as they expand and contract. 

What holds the lung open in its pleural space?

Surface Tension

What is the most important muscle for breathing and where is it located?

The diaphragm is located under the lungs, and divides the top half of the body from the bottom half

What structures pass through the diaphragm?

 Esophagus and aorta 

What structures allow the ribs to move up and down?

Lubricated hinges in the back; cartilage in the front 

What is involved in expelling air from the lung?

 The elastic connective tissue in the lungs contracts the lungs to their resting state 

The muscles of breathing are voluntary muscles. Why might that surprise us?

The act of breathing is involuntary in most cases so that we don't need to think about each breath, yet the muscles are voluntary so that we can control our breathing if we want to. 

When the diaphragm flattens out in breathing, what organs in the abdomen need to move out of the way?

Liver, stomach, intestines 

The movement of the organs when the diaphragm flattens would produce heat of friction. How is this minimized?

 Each organ is encased in a peritoneal sac that has lubricant between the visceral and parietal layers, allowing for slippage without friction.

What are the structures that branch off the trachea to supply air to each lung?

The Bronchi

Why is it that if a child inhales (aspirates) a small structure like a bean, it is more likely to go into the right lung than the left lung?

The right bronchus would allow something to drop straight into the right lung,while the left bronchus veers off steeply.

All bronchi are kept open by what structures?

 Cartilage rings or plates

How do bronchioles differ from bronchi?

Bronchioles don't have cartilage. 

What structures are included in the respiratory system?

Nasal cavity; pharynx; larynx; trachea; bronchi; lungs 

Where is the olfactory mucosa located and what does it do?

 The olfactory mucosa is located at the top of the nasal cavity. The epithelial cells interact with the nerves coming from the brain to produce our sense of smell. 

How does the size of the olfactory mucosa of humans compare to that of dogs?

he olfactory mucosa in humans is about the size of a postage stamp. In some dogs, it can approach the size of a handkerchief. 

Where are the pharynx and larynx located?

The pharynx and larynx are located at the back of the throat. 

How are the turbinates able to heat the air we breathe?

The tissue investing the turbinates is filled with big blood vessels that give off 

heat, warming the air as it passes through the nasal cavity. 

Where is the olfactory mucosa located in the nasal cavity?

At the top 

What is the function of odorant-binding proteins?

Odorant-binding proteins bind to odorant molecules and help us to detect different smells

What would normally keep food and water from going down the trachea instead of the esophagus?

The trachea is not in the main line of food exiting the oral cavity into the esophagus, also the epiglottis helps to prevent food from entering the trachea when swallowing. 

What is the advantage of having the trachea and esophagus meet in the oropharynx?

Speech is possible by having the trachea connected to the vocal chords and oral cavity. 

What are the tracheal rings made of?

 Hyaline cartilage

What is the function of mucus lining much of the respiratory tree, and what cells make the mucus?

Goblet cells make mucous to line the respiratory tree acting as a filter to trap dust and other particles that enter through the mouth or nose. 

How is the mucus able to be moved up the respiratory tree to the oropharynx?

Cells that line the trachea and bronchi have tiny hair-like filaments (cilia) that move the mucous up toward the mouth. 

What movement is necessary for cilia to move mucus?

Cilia move in a coordinated wave called a metachronal rhythm, which is like the "wave" you see spectators do at a ballgame. 

Mucus is too viscous to allow ciliary movement. How is this problem solved?

The cells produce a layer of fluid the same height as the cilia-as the cilia move through the fluid, the tips move the mucous over the fluid. 

 Describe the structure of the axoneme. 

An axoneme is made of tubules-nine doublets of tubules around the outside and one set in the middle. 

 What makes the cilium bend and move? 

One of the tubules in each doublet has cross-bridges which oscillate causing the tubules to slip in relation to each other, bending the cilium one way or the other. 

 All bronchi have what primary tissue which is lacking in bronchioles?

Cartilage. 

How does an alveolar duct differ from a bronchiole?

Alveolar ducts have alveoli attached to them whereas bronchioles do not. 

What structure is necessary for gas exchange in the lung?

Alveoli. 

What is an alveolar sac?

An alveolar sac is at the end of an alveolar duct.

Why must the alveolar wall be very thin?

Gas exchange occurs through the walls of the alveolar ducts so the walls need to be thin to facilitate the exchange. 

What are greater alveolar cells (type two pneumocytes), how do they differ from type one pneumocytes, and what do they produce?

Type one cells allow the diffusion of oxygen from air to blood; type two cells are foamy looking and produce surfactant to break the surface tension on the alveolus. 

Why do babies who are born a few months premature have trouble breathing?

Type two cells don't develop until the last month of a baby's development in utero. So the surfactant isn't produced in a baby born pre-term, and the baby's lungs cling together. 

Why is surfactant important for breathing?

The surfactant decreases the surface tension in the alveoli, preventing them from collapsing or sticking, and helping to facilitate gas exchange. 

Why does warm water taste "flat" compared to cold water?

Warm water doesn't allow oxygen to dissolve in it as easily as cold water does.

How is warm blood able to carry oxygen?

Hemoglobin in the blood has a high affinity for oxygen.

What is the shape of a red blood cell and why is this shape important?

Bi-concave disk; this shape provides the most surface area possible. 

What is the problem with red blood cells in sickle cell anemia?

 They are shaped like a sickle instead of as a bi-concave disk due to a mutation in one amino acid. 

How does the red blood cell keep its shape?

 A cytoskeleton holds the RBC in the right configuration. 

Why is the spleen removed sometimes in patients who have sickle cell anemia?

As the blood circulates through the spleen, the spleen destroys RBCs that are not right. So the spleen destroys sickle cell RBCs. The spleen is removed to prevent destruction of sickle cells. 

About how many different ways could you put the amino acids of hemoglobin together? How many are known to work normally?

1x10^600; only five configurations are known to work normally. 

What is the function of neutrophils and what do they look like?

Neutrophils contain lysosomes that eat bacteria. Their tiny granules don't show up as well so they don't stain as much as the others. 

What is the function of eosinophils and what do they look like?

 Eosinophils defend against parasites. They contain red granules that stain with the dye eosin. 

What is the function of basophils and what do they look like?

Basophils carry histamine and act as inflammation mediators. They contain large blue granules that stain with basic dyes. 

What type of cells do monocytes turn into?

Macrophages. 

What are the two basic types of lymphocytes found in blood and what are their functions?

B lymphocytes make antibodies; T lymphocytes kill virus infected cells. 

What are blood platelets and what is their function?

Platelets make blood clotting factors. 

Where is blood normally made?

 Marrow. 

What is a megakaryocyte and what does it produce?

Megakaryocytes are large cells in the bone marrow that produce platelets. 

What are the stages of development of a red blood cell in the marrow?

Basophilic erythroblasts; polychromatophilic erythroblast; picnotic nucleus is ejected; reticulocyte; mature erythrocyte. 

What is the difference between an erythroblast and erythrocyte?

Erythroblasts make red blood cells; erythrocytes are the mature red blood cells that lack a nucleus. 

If you see immature red blood cells in peripheral blood, what might be causing the problem?

Internal bleeding could cause more immature blood cells in the peripheral blood. 

What problems does smoking cause in the lungs?

Smoking particles get caught in the mucous; those particles that aren't caught in the mucous get gobbled up by macrophages. The macrophages with the carbon migrate to the connective tissue of lung lobules and stay there. 

What is a lung lobule?

A lobule is a unit of lungs supplied with a terminal bronchiole.