Tag: menstruation in females

Progesterone is a hormone released by the corpus luteum in the ovary. It plays important roles in the menstrual cycle and in maintaining the early stages of pregnancy. It may also be involved in the growth of certain cancers. During the menstrual cycle, when an egg is released from the ovary at ovulation (approximately day 14), the remnants of the ovarian follicle that enclosed the developing egg form a structure called as the corpus luteum. This releases progesterone and, to a lesser extent, oestradiol. The progesterone prepares the body for pregnancy in the event that the released egg is fertilised. If the egg is not fertilised, the corpus luteum breaks down, the production of progesterone falls and a new menstrual cycle begins. Estrogen or oestrogen is the primary female sex hormone and is responsible for development and regulation of the female reproductive system and secondary sex characteristics. Follicle stimulating hormone is produced by the pituitary gland. It regulates the functions of both the ovaries and testes. Lack or insufficiency of it can cause infertility or subfertility both in men and women. In females, an acute rise of LH ("LH surge") triggers ovulation and development of the corpus luteum. In males, where LH had also been called interstitial cell–stimulating hormone (ICSH), it stimulates Leydig cell production of testosterone. It acts synergistically with FSH. 

The clot is made up of blood cells, fibrins and endometrial tissues. Since the blood passes from uterus quickly then there is no time for anticoagulants to act. So, clots cannot be formed easily.

The menstrual cycle is the cycle of natural changes that occurs in the uterus and ovary as an essential part of making sexual reproduction possible. The length of it is an average of 28 days. So, blank 1 is 28 days.
Puberty is the process of physical changes through which a child's body matures into an adult body capable of sexual reproduction, It leads to the beginning of menstrual cycles in women. So, blank 2 is the menstrual cycle.
Menarche is the first menstrual cycle in females. So, blank 3 is menarche.
This cycle begins generally at the age of 12-13 and ends at the age of 45-55. So, option 4 is 45-50.
Menopause marks the end of menstrual cycle. So, blank 5 is menopause.
At around mid-cycle, when the egg is mature, it gets released from the ovary, pushed down to fallopian tube and is available to be fertilized in the process called ovulation. This occurs around 13th-14th day. So, blank 6 is 13$^{th}$ or 14$^{th}$ day and blank 7 is ovulation.
Progesterone is an endogenous steroid hormone and is secreted in the ovaries by the corpus luteum. So, blank 8 is progesterone.
After being released from the ovary, the egg is swept into the fallopian tube by the fimbria, which is a fringe of tissue at the end of each fallopian tube. So, blank 9 is fallopian tube
Thus, the correct answer is option (A), '(1) 28 days, (2) puberty, (3) menarche, (4) 45-50 years, (5) menopause, (6) 13th or 14th days, (7) ovulation, (8) progesterone, (9) fallopian tube'.

In human beings, menstrual cycle ceases around 50 years of age; that is termed as menopause. 

After the age of 45, the number of ovarian follicles decrease and the ovaries become less responsive to luteinizing hormone and follicle-stimulating hormone. Hence the ovaries stop producing estrogen and progesterone. So the menstrual cycle stops and reproductive capacity is arrested. Menopause marks the end of reproductive phase. Thus the correct answer is option A.

The reproductive cycle in primate female is menstrual cycle which is hormonal and reproductive tissue changes that occur in adult female mammals during their reproductive year and it is repeated at an average interval of about 28/29 days. It is an essential part of making sexual reproduction possible because it is necessary for the production of eggs.

The organisms which show differences in the two sexes of the same species are called as sexual dimorphic animals. The unisexual animals have either male or female reproductive organs. These organisms show differences in morphology, physiology and behaviour with respect to the sex of the organism. 

• Sexual dimorphism refers to the condition where the two sexes of the same species show different characteristics apart from the differences in their sex organs.
• In spiders, the drastic difference in size is seen where males are very small compared to females
• A common type of dimorphism is colouration which is commonly seen in many species of birds.
• Bees show difference of both size and pattern among Queen, Drone or worker bees.
• Among all the options, humans show least sexual dimorphism with nearly  same sizes and other similarities between both sexes.
• So, the correct option is 'Homo sapiens'.

Sexual dimorphism is the changes that are observed in two sexes of the same organism. In humans, the male and the female can be distinguished on the basis of many characters. The main property which is used for the distinction in the males and females is the presence of XX and XY set of chromosomes. The chromosomes contain the genes which are responsible for the expression of the characters. So, the sexual dimorphism is based on the genetic material. 

There is sexual dimorphism observed in the organisms which belong to the same species. There are differences in the characters of the female and male. In the birds, the males are more attractive than the females. The males have more colourful feathers in order to attract the female for sexual reproduction.