Ventricular Muscle Thickness: The walls of the left ventricle are thicker than the right due to the higher pressure needed to pump blood throughout the body, compared to the lower resistance in the pulmonary circulation.
Gallbladder: The gallbladder stores and concentrates bile produced by the liver, releasing it into the small intestine to aid in the digestion and absorption of fats.
Muscular and Elastic Artery Arteriole: Elastic arteries (like the aorta) buffer pressure from the heart, muscular arteries distribute blood to organs, and arterioles regulate blood flow into capillary beds via vasoconstriction and vasodilation.
Complement Cascade and Function: The complement system is a group of plasma proteins that, once activated, enhance immune responses by promoting inflammation, opsonizing pathogens for phagocytosis, and directly lysing microbial cells through the membrane attack complex.
Bone Marrow: Bone marrow is the primary site of blood cell production, including red and white blood cells and platelets, and contains stem cells that support hematopoiesis.
Arteries of the Brain: The brain is supplied by the internal carotid and vertebral arteries, which form the Circle of Willis, ensuring consistent cerebral blood flow.
Fenestrated Capillary: Fenestrated capillaries have pores in their walls that allow for rapid exchange of water and small solutes, commonly found in kidneys, intestines, and endocrine glands.
Hyperbaric Chamber: A hyperbaric chamber delivers 100% oxygen at elevated atmospheric pressure, enhancing oxygen delivery to tissues and used therapeutically for conditions such as decompression sickness, carbon monoxide poisoning, and chronic wounds.
Histology Small Intestines: The small intestines histology features villi and microvilli on its mucosal surface, which greatly increase the surface area for nutrient absorption; it also contains glands and lymphatic structures for digestion and immune defense.
Urea Cycle: The urea cycle occurs in the liver and converts toxic ammonia, a byproduct of protein metabolism, into urea, which is then safely excreted in the urine by the kidneys.
Fetal Circulation: Fetal circulation features shunts like the ductus venosus, foramen ovale, and ductus arteriosus that divert blood away from the liver and lungs, directing it efficiently between the heart and placenta.
Neonatal Circulatory System: At birth, the neonatal circulatory system undergoes major changes as fetal shunts close and the lungs take over oxygen exchange, resulting in the adult-like pattern of blood flow.
The Breakdown of Fatty Acids: Fatty acids are broken down in the mitochondria through a process called beta-oxidation, generating acetyl-CoA, which enters the citric acid cycle to produce ATP for cellular energy.
Hepatic Portal Vein System: The hepatic portal vein collects nutrient-rich blood from the gastrointestinal tract and transports it to the liver for processing before it enters general circulation.
Cartilages of the Larynx: The larynx contains several cartilages, including the thyroid, cricoid, arytenoid, and epiglottis, which support vocal cord function and protect the airway during swallowing.
Gross Anatomy of the Lungs: Each lung has lobes (three on the right, two on the left), a hilum for vessel entry/exit, and surfaces that fit into the thoracic cavity, facilitating gas exchange.
Photo of Placenta: A placenta photo typically shows the fetal side with vessels radiating from the umbilical cord and the maternal side with a spongy, vascular appearance that interfaces with the uterus.
Cardiac Muscle: Cardiac muscle is striated, involuntary muscle with intercalated discs that enable synchronized contractions, essential for continuous heart pumping.
Internal Anatomy of the Heart: The heart consists of four chamberstwo atria and two ventriclesalong with valves (tricuspid, mitral, pulmonary, and aortic) that ensure unidirectional blood flow through the cardiac cycle.
Partial and Total Pressure of a Gas: The partial pressure of a gas is its contribution to the total pressure in a mixture; total pressure is the sum of all individual partial pressures, key in respiratory gas exchange.
