Answer:
For a limb to regenerate, you need bone, muscle, blood vessels and nerves. There are adult stem cells, a kind of undifferentiated cell that can become specialized, that regenerate muscle, but they don't seem to activate.
A coral reef is a complex [ecosystem] of calcium carbonate shells that are home to microbes, algae, invertebrates, and fishes, and its high productivity helps provide great species richness.
I believe it's oxygenated or oxygen rich blood away from the heart.
Answer:
Estrogen and progesterone are both involved in preparing the endometrium for embryo implantation. Estrogen helps to ensure conception by increasing the amount of secretory glands in the uterus. Estrogen also increases blood supply to the endometrium.
Progesterone is crucial for embryo implantation and maintenance of pregnancy. Progesterone also enlarges secretory glands that produce carbohydrates, proteins and mucin that are required for embryo nourishment before implantation. Progesterone stabilizes endometrial muscles to prevent them from contracting during pregnancy.
Explanation:
- Estrogen and progesterone are steroid hormones of the reproductive system. Estrogen helps in conception whereas progesterone maintains pregnancy.
- Estrogen is secreted during the follicular phase of the menstrual cycle that promotes the growth and maturation of follicles in the ovary.
- Estrogen also induces oestrous behavior in females.
- Secreted by the corpus luteum, progesterone is also a steroid hormone, responsible for implantation of the embryo in the uterus.