The Hematopoietic System of the Bone Marrow new: The bone marrows hematopoietic system consists of stem cells that differentiate into various blood cell types, providing a continuous supply of cells vital for immunity, oxygen transport, and clotting.
Renin Aldosterone Angiotensin: The renin-angiotensin-aldosterone system (RAAS) regulates blood pressure and fluid balance by promoting vasoconstriction and sodium retention in response to decreased blood volume or pressure.
Cardiac Cycle vs Heart Sounds: The cardiac cycle corresponds with heart sounds, where the “lub” (S1) is caused by AV valve closure during systole, and the “dub” (S2) marks semilunar valve closure during diastole.
Lipid Metabolism: Lipid metabolism includes the digestion, absorption, storage, and breakdown of fats, with fatty acids used for energy production, membrane synthesis, or stored as triglycerides.
Podocytes: Podocytes are specialized cells in the kidney’s glomerulus with foot-like processes that wrap around capillaries, playing a crucial role in filtering blood to form urine.
The Hypothalamus Pituitary Complex: The hypothalamus and pituitary gland form a key regulatory complex that controls endocrine function via releasing and inhibiting hormones that act on the anterior and posterior pituitary.
Lower Limb Veins Anterior Posterior: The lower limb has anterior and posterior venous pathways, including superficial veins like the great and small saphenous veins, and deep veins like the femoral and popliteal veins.
Preembryonic Development: Preembryonic development spans from fertilization to implantation, including zygote formation, cleavage, morula, blastocyst formation, and initial attachment to the uterine wall.
The Structure of ATP Molecules: ATP (adenosine triphosphate) consists of an adenine base, a ribose sugar, and three phosphate groups, with high-energy bonds that release energy when hydrolyzed to power cellular processes.
Fetal Circulatory System: The fetal circulatory system includes unique structures like the ductus arteriosus and foramen ovale that shunt blood away from non-functioning fetal lungs and prioritize oxygen-rich blood from the placenta.
Exocrine and Endocrine Pancreas: The pancreas has both exocrine functionssecreting digestive enzymes into the duodenumand endocrine functions, producing insulin and glucagon to regulate blood sugar levels.
Major Respiratory Organs: Major respiratory organs include the nose, pharynx, larynx, trachea, bronchi, and lungs, all working together to move air, filter particles, and facilitate gas exchange.
Tooth: A tooth consists of enamel, dentin, pulp, and cementum, and is anchored into the jaw by periodontal ligaments; it functions in mechanical digestion and sensory perception.
Preembryonic Cleavages: Cleavage is a series of rapid mitotic divisions in the zygote that increase cell number without increasing size, forming the morula and eventually the blastocyst.
The Worldwide AIDS Epidemic: AIDS, caused by the HIV virus, has spread globally, with millions infected; it weakens the immune system by targeting CD4+ T cells, leaving individuals vulnerable to opportunistic infections and certain cancers.
Accessory Organs: Accessory digestive organs include the liver, pancreas, gallbladder, and salivary glands, which secrete enzymes and other substances aiding digestion but are not part of the GI tract itself.
Photo of Linea Nigra: The linea nigra is a dark vertical line that can appear on the abdomen during pregnancy due to hormonal changes; it typically fades postpartum.
Placenta Previa: Placenta previa occurs when the placenta partially or completely covers the cervix, posing a risk of bleeding during pregnancy and often requiring C-section delivery.
The Placenta: The placenta connects the developing fetus to the uterine wall, allowing nutrient and gas exchange, hormone production, and waste removal through the umbilical cord.
