Answer:Before the reaction, there are 4 oxygen atoms,and after the reaction, there are 4 oxygen atoms.The same is true for hydrogen atoms.So, atoms are not created or destroyed.This supports the claim that matter is conserved during a chemical reaction.
Explanation:
Answer:
The endometrial lining is shed during menstruation and is then regenerated by the hormone estrogen.
Explanation:
The menstrual cycle can be described in terms of:
1. <u>OVARIAN cycle</u>: divided into
-Follicular phase of variable length lasting between 7 and 21 days.
-Ovulation
-Luteal phase which is fairly constant and lasts between 12 and 16 days.
The most common cycle length is 28 days and this occurs in 15% of women in their reproductive age
.
The duration of flow is between 2-6 days.
2. <u>ENDOMETRIAL cycle</u>: divided into
-Proliferative phase where there is increase in growth of the functional layer and the endometrial glands under the influence of oestrogen.
-Secretory phase where endometrial changes are influenced by progesterone activity.
The endometrium is made up of the basal layer and the functional layer.
The basal layer remains intact throughout the cycle while the functional layer is shed during each menstruation.
Explanation:
A gene-edited pig's heart has been transplanted into a human for the first time. The procedure is a one-off, and highly experimental, but the technique could help reduce transplant waiting lists in the future
