Episode 73 - Digestive system - Structures and functions

Explains the stages of labor and the hormonal regulation of childbirth and breastfeeding. Discusses the role of oxytocin and prostaglandins in labor, and prolactin and oxytocin in milk production and ejection.

Follows the journey from sperm-egg fusion through blastocyst formation and implantation. Highlights the role of hCG, the formation of the placenta, and key hormones like progesterone, estrogen, and hCG in sustaining pregnancy.

Covers the menstrual, proliferative, and secretory phases of the uterine cycle. Describes how estrogen and progesterone prepare the endometrium for implantation and how their withdrawal leads to menstruation when pregnancy does not occur.

Explores the development and maturation of ovarian follicles through the follicular and luteal phases. Emphasizes the roles of FSH, LH, estrogen, progesterone, and inhibin, and explains how hormonal feedback regulates ovulation and corpus luteum function.

Details the process of sperm development, distinguishing between spermatogenesis and spermiogenesis. Explains the roles of Sertoli and Leydig cells and describes how FSH, LH, testosterone, and inhibin regulate sperm production through hormonal feedback loops.

Provides an introduction to the male and female reproductive systems, outlines homologous structures, and summarizes the functions of key reproductive hormones, including GnRH, FSH, LH, testosterone, estrogen, progesterone, and inhibin.

Focuses on how the enteric nervous system (ENS), autonomic input, and digestive hormones like gastrin, secretin, and CCK regulate motility and secretion during the cephalic, gastric, and intestinal phases of digestion.

Breaks down the chemical digestion of carbohydrates, proteins, and fats. Introduces digestive enzymes and their sources, the role of hydrochloric acid, and how bile salts aid fat digestion. Wraps up with the role of the gut microbiome in digestion and health.

Explores how food moves through the GI tract using peristalsis, segmentation, mixing waves, and mass movement. Discusses how factors like chyme composition and volume influence gastric emptying, and how neural and hormonal signals regulate motility.

Covers the six major functions of the digestive system—ingestion, propulsion, mechanical digestion, chemical digestion, absorption, and defecation. Differentiates between GI tract structures and accessory organs, and explains how food is broken down and moved through the digestive system.