<em>A egg cell is fertilised to form a zygote which is diploid(contains two sets of chromosomes) and then it divides again and again into a ball of cells by mitosis and then it is implanted</em>
Something from my biology a few years ago, HOPE IT HELPS Implantation is defined as the process by which the embryo attaches to the endometrial surface of the uterus and invades the epithelium and then the maternal circulation to form the placenta. Before the initiation of implantation, however, both embryo and endometrium should embark on an elaborated process in a time- and location-specific manner. The crosstalk between a receptive uterus and a competent blastocyst can only occur during a limited time span, known as the “window of implantation” (Psychoyos, 1986; Ma et al., 2003). The window of endometrial receptivity is restricted to days 16-22 of a 28-day normal menstrual cycle, 5-10 days after the luteinizing hormone (LH) surge (Navot et al., 1991). The uterus then continues into the non- receptive period for the remaining cycle as the late luteal
phase until menstruation ensues. It is not surprising that early pregnancy loss, which occurs during the peri-implantation period before pregnancy is confirmed clinically, is common in humans (Norwitz et al., 2001). The risk of spontaneous abortion significantly increases with implantation beyond this window (Wilcox et al., 1999). The synchronized molecular dialogue mediated by cytokines, a variety of growth factors, prostaglandins, matrix degrading enzymes and their inhibitors, and adhesion molecules is required for successful implantation. Infertility, the inability to conceive within a year of unprotected intercourse, affects one in seven reproductive-aged couples in Korea (Kim et al., 2014). It is necessary to investigate the hierarchical pathways that orchestrate the implantation process to develop solutions for implantation failure and to raise fertility rates in women.
Edwin Hubble's findings supporting the 'big bang theory' are as follows – almost all galaxies are moving away from us and the 'farther away a galaxy' is, the faster it is moving away.
Explanation:
The theory speaks of an ever-expanding universe and the proponent calculated the Law of Hubble.
a. Approximately half of those with anorexia nervosa go on to develop bulimia nervosa, indicating that the two disorders may not be distinct but may represent phases of the same eating disorder.
<u><em>Seeds are found in both flowering and non-flowering plants. Both plants reproduce, the difference being that the former reproduces through blossoms, whereas the latter reproduces through seeds or spores. Because both flowering and non-flowering plants have chlorophyll, they can both photosynthesise.</em></u>
Global warming can dramatically intensify the water cycle because this phenomenon is associated with an increase in temperature, thereby a higher amount of water is evaporated into the air and a higher amount of ice is melted at the poles. Warmer atmospheric air will have a higher amount of water vapor, increasing the frequency and intensity of rainstorms. In consequence, global warming can significantly increase the probability of flooding in coastal communities.
