Role of hCG in Early Pregnancy Shortly after the developing embryo implants into the endometrium it begins secretion of the hormone human chorionic gonadotropin (hCG) hCG is secreted during the fir...
Implantation of the Blastocyst Following human fertilisation, the newly fertilised ovum divides by mitosis to form two diploid nuclei (i.e. each nucleus contains two sets of chromosomes) and the cy...
Preventing Polyspermy Fertilisation is the fusion of one sperm cell and one ovum; this fusion of two haploid nuclei gives rise to a diploid zygote During sexual reproduction, many sperm are release...
Similarities Between Oogenesis & Spermatogenesis Sexual reproduction involves fertilisation; the fusion of sex cells, or gametes, from two parents Gametes are specialised, haploid cells The fus...
Drawing the Human Kidney The following elements should be included in a drawing of the human kidney The kidney should be roughly oval in shape with an inward curve on the side where it is connected...
Treatment of Kidney Failure Kidney failure can occur in one or both kidneys for a variety of reasons, such as Physical damage from an injury High blood pressure Diabetes Overuse of certain drugs (e...
Types of Nitrogenous Waste Nitrogenous waste comes from the breakdown of excess dietary amino acids and nucleic acids The waste is first converted into ammonia; some organisms excrete it in this fo...
ADH Living organisms can maintain a safe balance of water and solutes in their bodies by osmoregulation Osmoregulation is an example of homeostasis The kidneys play an important role in osmoregulat...
Conserving Water & the Loop of Henlé Animals that live in dry environments such as deserts depend on their ability to conserve water for survival Such animals often have very long loops of Henl...
