Secondary oocyte will complete meiosis when a sperm cell penetrates the oocyte membrane (fertilization).
The oocyte (is arrested at an early stage of the first meiotic division as a primary oocyte. During each menstrual cycle, one the day before ovulation gonadotropin hormone (luteinizing hormone) stimulates completion of meiosis 1. After the meiosis 1, 2 haploid daughter cells are formed: one becomes the secondary oocyte the other forms the first polar body. Newly formed secondary oocyte starts meiosis 2 which arrests at metaphase which will continue after the fertilization.
<span>Parathyroid Hormone (PTH) is a hormone that signals an increase in blood calcium (Ca2+) within into the bloodstream when below normal ranges. When blood calcium is within normal ranges Calcitonin is released from the thyroid to stop blood calcium from increasing thus maintaining equilibrium.</span>
Answer: four criteria to establish a causative relationship between a microbe and a diseases
Explanation:
1- "Bacteria must be present in every case of diseases"
2- "Bacteria must be isolated from the host with the diseases and grown in pure culture"
3- "The specific diseases must be reproduced when a pure culture of bacteria is inoculated into a healthy susceptible host"
4-"Bacteria must be recovered from the experimentally infected host"
