Ch 12 Review Flashcards
Describe how diffusion is involved in the
respiratory systems of
(a) earthworms
Earthworms do not have lungs.
They breathe through their skin.
Oxygen and carbon dioxide pass through the earthworm’s skin by diffusion.
For diffusion to occur, the earthworm’s skin must be kept moist.
Describe how diffusion is involved in the
respiratory systems of
(b) grasshoppers
have a tracheal system, which’s a system of tubes that extend through their bodies
-Air enters and leaves the system through openings in the body surface.
-The larger tubes, called tracheae, branch into
smaller and smaller tubes called tracheoles,
which extend to nearly every cell in the
insect’s body.
-Gas exchange occurs along the moist membrane at the tips of the tracheoles
Explain why most terrestrial organisms need to
have respiratory systems that are found inside
rather than outside the organism
Most terrestrial animals have evolved internal respiratory surfaces, such as tracheal
systems and lungs
- helps minimize the loss of moisture.
What are two ways in which the air is changed
as it passes through the nose?
-Many of the impurities in air, such as dirt and bacteria, are filtered by hair and mucus in your nose.
-Air is warmed and moisture is added.
What is the function of the epiglottis?
When you swallow, the epiglottis covers the air pathway to prevent food from entering the trachea, instead of the esophagus
What is the function of the diaphragm?
Upon inhalation, the diaphragm contracts and flattens and the chest cavity enlarges.
This contraction creates a vacuum, which pulls air into the lungs.
Upon exhalation, the diaphragm relaxes and returns to its domelike shape, and air is forced out of the lungs
Describe the process of the diffusion of oxygen
and carbon dioxide in the lungs
Oxygen in the air you inhale dissolves in the film of
moisture on these epithelial cells. The oxygen then diffuses into a web of capillaries surrounding each alveolus and enters red blood cells, binding to hemoglobin.
Hemoglobin increases the efficiency of gas exchange by creating a diffusion gradient. In other words, when the hemoglobin in a red blood
cell binds to the oxygen, it removes the oxygen from the plasma.
Oxygen then keeps on diffusing from the alveolus into the plasma
As cellular respiration produces energy, carbon dioxide is produced as a by-product of that process. Carbon dioxide diffuses the opposite way to oxygen, from the capillaries across the epithelial cells and into the alveoli.
The carbon dioxide is carried away from the cells and deposited in the lungs.
Then the carbon dioxide is expelled back up the trachea, through the nose or mouth, and into the environment.
Describe how breathing is controlled in the
brain
Most of the time, breathing is controlled by the medulla oblongata, a part of the brain located
near the top of the spinal cord.
The medulla oblongata sends nerve signals to
the diaphragm and rib muscles, causing them to contract and relax.
Why is the process of ventilation described
as a passive process?
Because breathing is an involuntary process you seldom realize is occurring
Distinguish between bronchi,
bronchioles, and alveoli
The trachea forks into two bronchi (singular, bronchus), which are air tubes that connect the trachea to the lungs
Within each lung, the bronchus branches repeatedly into finer and finer tubes called bronchioles
Each bronchiole ends in grapelike clusters of tiny air sacs called alveoli
explain how the movements of the ribs, chest and diaphragm are involved in the process of breathing
*When your diaphragm and rib muscles contract, you inhale.
Your inhalation expands your chest cavity, which increases the volume of your lungs, resulting in reduced air pressure within the alveoli.
Since air tends to move from an area of higher pressure to an area of lower pressure, air rushes in through your nose or mouth and fills
the alveoli.
*When your diaphragm and rib muscles relax, your lung volume decreases, causing higher air pressure in the alveoli.
Air rushes from your lungs out through your nose or mouth as you exhale.
describe the process of how when the brain senses a lowered pH level in your blood, it initiates a faster breathing rate.
1) During exercise or other activity, cell metabolism
increases and produces more CO2.
2) More CO2 dissolves in plasma, forming carbonic
acid, which lowers plasma pH slightly.
3) Receptors in the brain sense the drop in pH and send nerve signals to increase breathing rate.
4) Increased breathing rate quickly removes more CO2 from blood. Blood pH rises slightly, returning to normal.
5) Homeostasis, CO2 level in body
Define “homeostasis.”
state of internal stability maintained by the body.
What is sinusitis?
a condition caused by viruses or bacteria in which the sinuses become swollen and irritated
(a) Define the term “asthma.”
a chronic disorder of the respiratory system in which airways become narrowed
(b) Explain how asthma may affect the function
of the respiratory system
Smooth muscles surround the bronchi and bronchioles.
When these muscles contract, they narrow the airway, making breathing very difficult.
Describe the condition called bronchitis
When the bronchioles or the airways that connect the alveoli and the trachea become irritated or infected, they swell and produce excess mucus, a condition called bronchitis
What happens in the lungs of a person with
emphysema?
lungs inflate
(a) What does COPD stand for?
(b) When is this condition found?
-Chronic obstructive pulmonary disease (COPD)
-occurs when chronic bronchitis and emphysema are found together
Why do patients with cystic fibrosis need daily
physical therapy?
Patients must participate in daily physical therapy to ease the flow of air.
(a) What does SARS stand for?
(b) What type of virus causes SARS?
Severe Acute Respiratory Syndrome
caused by a type of virus called a coronavirus
What are groups of cancer cells called?
tumours
What does a respirometer measure?
measure a patient’s breathing movements and lung capacity.
Samples of blood and mucus are observed so that the presence of abnormalities can be identified
How does smoking affect the respiratory
system?
The toxic substances in tobacco smoke irritate the cells lining the bronchi and destroy the cilia.
Without cilia, these cells lose the ability to move particles out of the respiratory system.
The smoker must cough frequently to try to clear the mucus that is no longer moved by the cilia.
Once they lose the ability to remove these harmful particles from their lungs, smokers are at a greater
risk for diseases caused by these particles
(a) What is an insulin pump?
(b) Why is it used?
provides a convenient and reliable
alternative to injections.
this pump administers a reliable dosage of insulin through a tube that is connected to the blood stream
How does diabetes show the
interconnectedness of body systems?
Diabetes is a group of diseases in which high levels of blood glucose result from a problem with insulin secretion, insulin action, or both.
it affects your heart and your whole circulation.
That includes small blood vessels in your kidneys, eyes, and nerves (nervous system)
The damage starts with high blood sugar (glucose) and insulin levels
How is Type 2 diabetes different from Type 1
diabetes?
In Type 1 diabetes, the cells of the pancreas are damaged so that they cannot produce insulin.
In Type 2 diabetes, the body cells do not respond to insulin appropriately
-reasons for this increase include rising rates of obesity and the increasingly sedentary lifestyle of Canadians
(a) What is a sedentary lifestyle?
(b) What is the relationship between a
sedentary lifestyle and Type 2 diabetes?
being inactive all the time
-leads to type 2 diabetes and causes it
