Chapter 39 Respiratory System Flashcards
True or False: Respiratory gases (e.g., oxygen and carbon dioxide) rely on transport proteins to cross cell membranes.
False
What are the important respiratory gases?
oxygen and carbon dioxide
What is oxygen used for in cells?
production of ATP
What organelle uses oxygen?
mitochondria
What biochemical pathway uses oxygen?
electron transport chain
How is carbon dioxide produced?
citric acid cycle
What organelle produces carbon dioxide?
mitochondria
How do gases enter and leave the body?
diffusion
2 Requirements of a Respiratory Surface
- large surface area
- short diffusion distance
What drives the diffusion of gases?
partial pressure gradients
Partial Pressure
hypothetical pressure of that gas if it alone occupied the volume of the mixture at the same temperature
Does gas diffusion require active transport?
NO
Which has more oxygen: air or water?
air
What medium does oxygen diffuse easily: air or water?
air
What takes more energy to move: air or water?
water
Do all animals have specialized gas exchange structures?
YES
Pharynx leads to ___.
trachea
Trachea branches into ___.
bronchi
Bronchi branch into ___.
bronchioles
Bronchioles end at ___.
alveoli
Where does gas exchange occur in mammalian lungs?
alveoli
Structure of Alveoli
- very thin walls
- blood vessels surround the walls
How do gases enter and leave alveoli?
blood passes through the capillaries next to the cell of alveolus
Function of Diaphragm
contracts to cause inhalation
Tide Flow
the volume of air moved into or out of the lungs during a normal breath
How is breathing regulated? What is it controlled by?
- controlled by brain stem and medulla
- pons help regulate
What will an increase of firing of motor neurons cause?
inhalation of lungs
What will an decrease of firing of motor neurons cause?
exhalation of lungs
What does the medulla contain?
respiratory motor neurons
What types of receptors monitor oxygen and carbon dioxide?
chemoreceptors
Where are chemoreceptors found in respiratory system?
surface of medulla and surface of arteries leaving the heart
What does the surface of the medulla do?
monitor carbon dioxide in cerebrospinal fluid
What do the arteries do in the respiratory system?
- pick up oxygen levels
- sends signals to medulla
- will change breathing levels at extreme altitude, low blood volume, low blood pressure
How is most of the oxygen transported in vertebrates?
red blood cells
Is there any oxygen dissolved in plasma?
YES, very little
Is carbon dioxide highly soluble in blood?
YES
How is carbon dioxide transported in blood?
as bicarbonate
What is the function of carbonic anhydrase?
Catalyze the reaction between CO2 and water into carbonic acid.
True or False: The diaphragm is composed of voluntary smooth muscle.
False
As temperature increases, solubility of oxygen in water ____.
decreases
Oxygen is used by ____, and carbon dioxide is produced by ____.
electron transport chain….citric acid cycle (Krebs cycle, tricarboxylic acid cycle)
The movement of oxygen and carbon dioxide between the blood in the tissue capillaries and the cells depends most directly upon ____.
diffusion of respiratory gases down a partial pressure gradient
Some relatively large multicellular aquatic animals lack a circulatory system and are able to manage gas exchange by ____.
having short diffusion distances from the external aquatic environment to their cells
Emergency medical technicians (EMTs) suspect that a victim of a serious accident has suffered an injury to the brainstem because his breathing has continued but is irregular. Specifically, which part of the brain is the likely location of where the injury occurred?
Pons
Receptors that respond to levels of oxygen in the blood are an example of a ___.
chemoreceptor
