Posted inCell
Male Chromosomes
Male chromosomes consist of 46 total, including 22 autosomal pairs and one X and one Y sex chromosome determining maleness via SRY gene triggering testicular development, with Y carrying few…
Posted inOrgans
Layers of the Gastrointestinal Tract
The gastrointestinal tract shares four concentric layers from esophagus to rectum: innermost mucosa with epithelium, lamina propria, muscularis mucosae; submucosa dense connective with glands, vessels, Meissner plexus; muscularis propria inner…
Posted inMuscles
Action Potential Heart Contraction
A heart physiology illustration linking action potentials to contraction demonstrates how electrical signals drive each heartbeat. It traces the spread of an action potential through cardiac muscle cells, beginning with…
Posted inMedical
Embryo Week 3
Embryo week 3 is a pivotal period of gastrulation where the primitive streak appears on the epiblast, cells ingress to form mesoderm and definitive endoderm, displacing hypoblast, while the notochord…
Posted inOrgans
Cardiac ConductionN
A cardiac conduction diagram maps the heartÂ’s electrical system from the sinoatrial node through the atrioventricular node and into the ventricles. It shows how timing and coordination ensure efficient contraction.…
Posted inMedical
DeglutitionN
Deglutition, more commonly known as swallowing, is a remarkably coordinated process that moves food or liquid from the mouth to the stomach in three distinct phases while protecting the airway…
Posted inOrgans
Development of Lower Respiratory SystemN
The development of the lower respiratory system begins early in embryonic life around week four when a respiratory diverticulum buds off the ventral foregut endoderm, separating from the esophagus and…
Posted inDisease
Occluded Coronay Arteries
Occluded coronary arteries from atherosclerotic plaque rupture and thrombosis deprive downstream myocardium of oxygen, causing ischemia then infarction if prolonged, with left anterior descending affecting large anterior wall, right coronary…
Posted inOrgans
Blood Flow in the Kidneys
A detailed illustration of blood flow in the kidneys highlights how circulation supports filtration and waste removal. The diagram traces blood entering through the renal artery, branching into smaller vessels,…
Posted inMedical
Urine Color Chart
Urine color normally pale straw yellow from urochrome pigment concentration, clear dilute dark concentrated dehydration, colorless overhydration diabetes insipidus, cloudy infection, pink red blood beets berries hematuria, orange medications bile…
Posted inWomen
Photo of Linea Nigra
Linea nigra is a dark vertical line running from pubis to sternum or navel on pregnant abdomen, resulting from melanocyte-stimulating hormone increase darkening the normally faint linea alba, more pronounced…
Posted inOrgans
Arteries of the Brain
A cerebral circulation map displays arteries supplying the brain, including the carotid arteries and Circle of Willis. The interconnected layout highlights redundancy in blood supply, which helps protect brain tissue…
Posted inMedical
Fetal Circulation
Before birth, the fetus relies on unique circulatory shortcuts because its lungs are non-functional and it gets oxygen and nutrients from the placenta via the umbilical cord. Oxygen-rich blood enters…
Posted inMedical
Hyperbaric Chamber
Hyperbaric chambers deliver oxygen therapy by placing patients in pressurized environments, typically 2-3 atmospheres, forcing far more oxygen to dissolve in plasma beyond what hemoglobin carries, useful for decompression sickness…
Posted inMedical
Mechanical and Chemical DigestionN
Mechanical digestion physically breaks food into smaller pieces starting with mastication in mouth, churning in stomach via three muscle layers producing chyme, segmentation in small intestine mixing with enzymes, and…
Posted inOrgans
Gallbladder
The gallbladder is a small pear-shaped sac tucked under the liver that stores and concentrates bile produced by hepatocytes. Between meals, the sphincter of Oddi stays closed, so bile backs…
Posted inCell
Primary and Secondary Antibody Respons new
Primary antibody response upon first antigen encounter is slow, IgM appearing days 4-10 from naive B cells activated in nodes or mucosa, peaking low then declining, while secondary anamnestic from…
Posted inCell
Germ Layers
During early embryonic development, the blastula reorganizes into three primary germ layers that give rise to all tissues and organs. The outer ectoderm forms skin, hair, nails, and the nervous…
Posted inMedical
Blood Volume Loss and Homeostasis
An illustration of blood volume loss and homeostasis explains how the body responds to bleeding or dehydration. It shows sensors detecting reduced volume or pressure, triggering responses such as increased…
Posted inMedical
Lower Limb Arteries Anterior Posterior
Lower limb arteries arise from the femoral artery continuing the external iliac, viewed anteriorly showing profunda femoris branching deep into thigh muscles, then popliteal behind the knee giving genicular branches,…