Heart/Pumps/Chambers: the circulatory system is a body system that includes a network of vessels: the arteries, veins, and capillaries and a pump: the heart. Human hearts have 4 chambers, where there are 2 atria and 2 ventricles.

Atrium: the atria are the upper chambers of the heart. The right atrium receives deoxygenated blood from the systemic circuit, which it sends to the right ventricle. The left atrium receives oxygenated blood from the pulmonary circuit (i.e. from the lungs), and then sends this blood to the left ventricle.

Ventricle: these are the lower chambers of the heart. When the right ventricle contracts, it pumps deoxygenated blood through the pulmonary arteries and into the pulmonary circuit to get oxygenated. When the left ventricle contracts it pumps oxygenated blood through the aorta and into the systemic circuit.

Open circulatory system: this is primarily found in invertebrate animals, where the circulatory fluid directly bathes the internal organs, even though this circulatory fluid can be moved by a pumping heart.

Closed circulatory system: in this system, blood unidirectionally circulates the body through blood vessels. Here, blood starts from the heart and flows through either of 2 circulatory routes, and eventually returns to the heart.

Introductory Animal Physiology, 2nd Edition. (2021). Retrieved March 10, 2022, from https://ecampusontario.pressbooks.pub/introanimalphysiology2nded/.

Red blood cell/Erythrocyte: contain a metalloprotein called hemoglobin, allowing oxygen to be bound to the erythrocyte in order to transport the oxygen around the body.

Heme: this is the part of hemoglobin containing iron, and which binds to oxygen.

Hemoglobin: allows oxygen to be bound to the erythrocyte (red blood cell).

Oxygen dissociation curve: this graph displays the relationship of pO2 to the binding of oxygen to heme. This can be used to display the effects of different environment conditions (ex. varying pH or temperature) on the dissociation of oxygen from heme to be used by the body for cellular respiration.

pO2: the partial pressure of oxygen.

O2 saturation: this is the percent of heme (in all the blood) that are bound to oxygen. Thus, the lower the O2 saturation, the less O2 there is in the heme.

Bohr effect: this is an effect demonstrating the relationship between pH and oxygen's affinity for hemoglobin, which can be seen on the oxygen dissociation curve. The Bohr effect shows that a lower (more acidic) pH increases oxygen dissociation from hemoglobin.

Oxygen transport: more oxygen transport allows more cellular respiration to occur, thus increasing ATP production and building of new structures in the body (see Figure 3.1)

Carbon dioxide transport: see Figure 3.6

Introductory Animal Physiology, 2nd Edition. (2021). Retrieved March 10, 2022, from https://ecampusontario.pressbooks.pub/introanimalphysiology2nded/.

GLOSSARY

Red blood cell/Erythrocyte: contain a metalloprotein, hemoglobin, which serves to bind oxygen molecules to the erythrocyte.

Heme: the portion of hemoglobin that contains iron, and binds the oxygen.

Hemoglobin: serves to bind oxygen molecules to the erythrocyte.

Oxygen dissociation curve: a graph that describes the relationship of partial pressure to the binding of oxygen to heme and its subsequent dissociation from heme.

pO2: partial pressure of oxygen.

O2 saturation: when considering the blood as a whole, the percent of the available heme units that are bound to oxygen at a given time is called hemoglobin saturation.

Bohr effect: a phenomenon that arises from the relationship between pH and oxygen’s affinity for hemoglobin: A lower, more acidic pH promotes oxygen dissociation from hemoglobin.

Oxygen transport: Increasing oxygen transport allows cells to ramp up cellular respiration and thus ATP production, the energy needed to build new structures. (see Figure 3.1)

Carbon dioxide transport: Figure 3.6

Heart/Pumps/Chambers: The circulatory system is a network of vessels—the arteries, veins, and capillaries—and a pump, the heart. In humans, the heart is divided into four chambers: two atria and two ventricles.

Atrium: The right atrium receives deoxygenated blood from the systemic circulation through the major veins: the superior vena cava, which drains blood from the head and from the veins that come from the arms, as well as the inferior vena cava, which drains blood from the veins that come from the lower organs and the legs. The left atrium receives the oxygen-rich blood from the lungs.

Ventricle: The right ventricle contracts, pumping the blood to the lungs for reoxygenation. The left ventricle is where the blood is pumped into the aorta.

Open circulatory system: are found in invertebrate animals in which the circulatory fluid bathes the internal organs directly even though it may be moved about with a pumping heart.

Closed circulatory system: Blood circulates inside blood vessels and circulates unidirectionally from the heart around one of two circulatory routes, then returns to the heart again.