Please enable JavaScript.

Coggle requires JavaScript to display documents.

STAGES OF REPRODUCTION - Coggle Diagram

- - - - When the first spermpenetrates the ovum´s membranes, the nuclei of gametes fuse. It is then that the zygote forms. Once fertilised, the ovum is enveloped by a protective cover that stops other sperm from coming in.
- - - - During the first weeks, the cell mass that develops in the uterus isreferred to as the embryo. When the embryo develops a human shape it is known as the fetus.
        
        The development of the embryo has three stages:
        
        Embryinic
        
        The embryo devlops in the interior of a membrane known as amnion, which fills up with amniotic fluid that protects the fetus. At the beginning of gestation, a mucus plug, which closes thye cervix to protect the fetus from the outside, is formed
        
        fetal
        
        Germinal
- - - - Menstrual cycle purpose is to prepare the uterus to host the embryo in case the ovum is fertilised.
        
        There are three stages in this cycle:
        
        Menstrual phase, or period: this is considered the beginning of the cycle. Due to a shrp decrease of the ovary´s hormonal secretions, the thick mucus of the uterus breaks off and is released to the exterior along with blood from the blood vessels. The menstrual flow last about 4 to 5 days.
        
        Secretory phase: the lining of the uterus reaches its maximum thickness and is prepared to host and feed the fertilised ovum. If the ovum is fertilised, the corpus luteum continues to secrete progesterone and the lining of the uterus does not break off.
        
        Proliferation phase: the uterine mucus is reconstructed thanks to the action of the estrogen produced by the ovaries th last 11 days.
    - - Oogenesis occurs regularly in womwn from puberty onwards. It takes place aproximately every 28 days. Its purpose each time is the formation, maduration and release of an ovum.
        
        The ovarian cycle takes places in three stages:
        
        Fillicular phase: tis last 14 days. SHF stimulatesthe development of one or several follicles at the same time, although normally only one of them matures.
        
        Secretory phase:Once the ovum is released, the corresponding area transforms into a mass of cells that produces and secretes the hormone progesterone. After 10 to 12 days, the corpus luteum degenerates and stpos secreting hormones, which starts, turn, a new cycle.
        
        Ovulation: this consist sof the release of an ovum through the ovary as a consequence of the production of the hormone