Olfaction is
The "master cells" of the immune system that initiate and coordinate...
Which main tissue type of the circulatory system enables diffusion...
B cells or T cells are
The innate chemical substance produced by basophils that cause blood...
The simplest animals with a closed circulatory system are
Which of the following is an immediate effect of histamine release?
Which blood vessels have the thinnest walls?
In aquatic organisms, highly folded structures that exchange gases...
A waste product of respiration is
During which phase of the heartbeat does the heart fill with blood?
Blood clots are formed by platelets and the plasma protein
Antibodies are
The lower respiratory tract is composed of what?
HIV has a high mutation rate and can use this to its advantage to...
The most important signal that the brain uses to set the breathing...
Aerobic respiration consumes ___ gas and generates ___ gas as a...
If you were to move from around sea level to a much higher altitude,...
In birds, deoxygenated air moves from the lungs into the ___ before...
The two main functions of the lymphatic system are
Passive immunity depends upon
___ can destroy infected cells
The ___ is a passageway shared by both food and air
Which of the following is a likely advantage of a three-chambered...
The two largest veins of the body that deliver blood to the right...
Blood proteins are involved in all of the following activities except
The body's innate defenses against infection include
The movement of air across the vocal cords in the ___ produces...
There are approximately ___ alveoli in the lungs of an adult...
The walls of the bronchioles are made up of
What name is given to the sheet of muscle that helps move air in and...
Within the lungs, gas exchange occurs across
How do ice fish transport oxygen in their blood?
Which of the following factors contributes to the flow of blood in...
What type of blood vessel is solely responsible for exchange between...
How does an insect "hold its breath"?
What drives the movement of oxygen from the alveoli into the...
Why are gills only found in aquatic animals?
Bacterial infections can cause a serious, potentially fatal systemic...
The upper respiratory tract is composed of what?
What type of immune response is always disadvantageous to a person?
The anatomical arrangement in which two adjacent currents flow in...
Hemoglobin is a(an) ___rich pigment that carries oxygen
Which of the following types of cells does HIV preferentially infect?
Medullary breathing centers directly sense and respond to
In mammals, which of the following vessels transports oxygenated blood...
Oxygen-poor blood is carried from the heart of a mammal to the lungs...
Blood is pumped from the heart to the lungs by the
The main function of the AV node is to
Emphysema is caused by destruction of the walls between alveoli...
Carbon Dioxide sensors are found in
Which of the following cell types is responsible for humoral immunity?
In arthropods, thee extensively branched internal tubules that connect...
Which of the following is a function of the circulatory system?
Where would fish have the highest concentration of oxygen in their...
The tough connective tissue sac surrounding the mammalian heart is the
The chamber of the mammalian heart that is the most powerful is the
During ventricular systole, the ___valves ___
Which of the following cell types is responsible for cell-mediated...
The human lymphatic system consists of all of the following structures...
One kind of vaccine consists of
Which of the following function primarily as phagocytes
Sleep apnea is more common in people who are overweight. Excess fat in...
In the systemic circulation, ___ is expelled from the blood...
Ice fish would have which of the following circulatory systems?
High-flying birds are able to obtain enough oxygen even when the air...
Animals that effectively use their body surface for gas exchange must
Which of the following animals has a single circuit of blood flow and...
The location of the heart's pacemaker is a specialized region of...
Natural killer cells
Which of the following organisms has a respiratory system that does...
Which of the following helps activate our nonspecific (innate) defense...
Which of the following is not a main function of the respiratory...
Which of the following compounds is produced and secreted by mast...
In which of the following human blood vessels is the blood pressure...
Which kind of vessel has the lowest blood velocity?
Which of the following wander through the interstitial fluid eating...
When you cut yourself, the damaged cells immediately release chemical...
What type of cell acts as an intermediary between humoral and...
In the pulmonary circulation, ___ is expelled from the blood...
The innate chemical substance that alerts other cells and components...
When you hold your breath, which of the following blood gas changes...
Most CO2 is transported to the lungs
The substance that when activated triggers a chain reaction that...
Which of the following animals has a three-chambered heart?
Which chamber of the heart becomes enlarged in a person with...
What drives the movement of carbon dioxide from tissue into the...
Some complement proteins
The major result of the inflammatory response is to
The type of white blood cell that develops into a macrophage is the
In humans, which blood vessels have valves?
Which of the following is characteristic of the circulatory system of...
In mammals, blood returning from the head will pass through...
From the left ventricle, oxygen-rich blood flows through the
The innate chemical defense substance that activates T cells and...
Sleep apnea is more common in people who are overweight. Excess fat in...
When you exhale, you
In Cystic Fibrosis, a thick dry mucus builds up in the alveoli. Which...
Which of the following animals can obtain the oxygen they need by...
Which of the following statements about blood clotting is true?
Which main tissue type of the circulatory system regulates airflow to...
A substance that can elicit an immune response is called
The basic function of activated T cells is to identify
Which of the following options correctly lists the direction of carbon...
What substance, produced by virus-infected cells, diffuses to...