Vertebrate Circulatory System Quiz

Vertebrate Circulatory System Components

• Blood: A connective tissue consisting of plasma, red blood cells (erythrocytes), white blood cells (leukocytes), and platelets. Plasma transports nutrients, hormones, and waste products. Red blood cells carry oxygen. White blood cells fight infection. Platelets help with blood clotting.

• Vessels: A network of tubes (arteries, veins, capillaries) that transport blood throughout the body. Arteries carry blood away from the heart, veins carry blood towards the heart, and capillaries facilitate the exchange of substances between blood and tissues.

• Heart: A muscular pump that propels blood through the circulatory system. It has chambers (atria and ventricles) that contract rhythmically to create pressure differences, moving blood unidirectionally.

Single vs. Double Circulation

• Single Circulation: Blood passes through the heart once per complete circuit. Found in fishes. Blood is pumped from the heart to the gills to pick up oxygen and then to the body tissues. Blood pressure is lower compared to double circulation.

• Double Circulation: Blood passes through the heart twice per complete circuit. Found in amphibians, reptiles, and mammals. Separate pulmonary (lungs) and systemic (body) circuits improve oxygen delivery and efficiency. Higher blood pressures compared to single circulation.

Embryonic Development of the Cardiovascular System

• Embryonic cardiovascular development involves formation of the heart tube from mesoderm. The tube then develops into distinct chambers (atria and ventricles). Blood vessels also form and grow in association with the developing heart tube.

Comparison of Blood Vessels Across Vertebrates

• Differences in blood vessel structure and distribution are related to circulatory efficiency and lifestyle. Changes in wall thickness and diameter of arteries to deal with higher and lower pressure in different vertebrates.

Comparison of Hearts Across Vertebrates

• Heart structure varies among vertebrate groups. Fishes possess a two-chambered heart. Amphibians and reptiles tend to have three-chambered hearts, while birds and mammals have four. Evolutionary changes in heart chambers reflect adaptations for varying metabolic demands and oxygen requirements.

Cardiovascular System Specialized Adaptations Across Vertebrates

• Fetal Circulation: Allows for oxygen transfer from mother to fetus. Features a special vessel shunting blood from lungs, and a high blood pressure gradient between the placental and fetal vessel systems.

• Placental Circulation: A unique feature of mammals facilitating nutrient and gas exchange between the mother and offspring during gestation.

Vertebrate Lymphatic System Components

• Lymph: Fluid containing proteins, fats, and waste products that leak from capillaries.

• Lymphatic Vessels: A network of vessels transporting lymph towards the cardiovascular system. These capillaries intersect to form larger vessels that eventually empty into the blood circulatory system. These vessels contain valves to prevent backflow of lymph.

• Lymph Nodes: Small, bean-shaped structures along lymphatic vessels that filter lymph—contain immune cells to fight infection.

Test your knowledge on the components of the vertebrate circulatory system, including blood, vessels, and the heart. Explore the differences between single and double circulation. This quiz will help reinforce key concepts related to vertebrate anatomy and physiology.