In this chapter, we will learn about the various methods of reproduction in animals the human reproductive system, gametogenesis and fertilization, early embryology, parturition and reproductive health.
Sponges, also known as poriferans, primarily reproduce through two main methods: 1. Sexual Reproduction Internal Fertilization: Some species have separate sexes, and internal fertilization occurs when sperm released by male sponges are captured by specialized cells in female sponges. Fertilization then occurs within the female sponge, leading to the development of larvae. External Fertilization: In … Read more
1. Definition: It’s an early embryonic stage with a spherical arrangement of cells and a central fluid-filled cavity. 2. Formation: After the zygote’s intricate cell division in the morula stage, the blastula becomes a crucial milestone in development. 3. Hollow Structure:The blastula’s distinctive hollow nature with a fluid-filled cavity, the blastocoel, sets the stage for subsequent development. … Read more
The testis, a vital male reproductive organ, has a simple structure with sperm-producing tubules and tissue between them. 1. Seminiferous Tubules: Key units for sperm production, supported by nourishing Sertoli cells. 2. Interstitial Tissue (Leydig Cells): Leydig cells, between tubules, produce testosterone for male reproductive functions. 3. Spermatogonia: Germ cells in tubules undergo mitosis to … Read more
Parturition, commonly known as childbirth, is a complex process involving the expulsion of the fetus from the mother’s uterus. It occurs in three main stages: dilation, expulsion, and after birth or placental delivery. 1. Dilation: During the dilation stage, uterine contractions gradually move the baby towards the cervix, causing pain from blood vessel compression. Strengthened by … Read more
The menstrual cycle comprises distinct phases: The menstrual cycle unfolds in a series of well-defined phases: 1. Menstrual Phase: This initial stage spans 3-7 days and involves the shedding of the uterine lining. It signifies the start of a new cycle. 2. Proliferative Phase / Follicular Phase / Post Menstrual Phase: In this dynamic period, ovarian follicles … Read more
Colostrum is the first milk produced by mammals, including humans, in the initial days after giving birth. It’s a thick, yellowish fluid that provides essential nutrients, antibodies, and immune factors to newborns. Colostrum is rich in proteins, vitamins, minerals, and antibodies, offering vital support to a newborn’s immune system and helping in the development of … Read more
The causative organism of syphilis is a bacterium called Treponema pallidum.
Tubectomy, also known as female sterilization, is a surgical procedure that involves closing, blocking, or sealing the fallopian tubes to prevent eggs from reaching the uterus for fertilization. This procedure is a form of permanent contraception and is commonly chosen by individuals or couples who have completed their desired family size or do not wish … Read more
Condoms Condoms are one of the most accessible and widely used mechanical contraceptives. They are thin, flexible sheaths typically made from latex, polyurethane, or natural materials like lambskin. Used during sexual intercourse, condoms act as a barrier, preventing sperm from reaching the vagina and reducing the risk of sexually transmitted infections (STIs). Their effectiveness largely … Read more
In vitro fertilization (IVF) is a fertilization method where an egg is combined with sperm outside the body, typically in a controlled laboratory environment using a test tube or specialized dish. This process creates a zygote or early-stage embryos containing up to 8 blastomeres. Following fertilization, these embryos can be transferred back into the fallopian … Read more