Female Reproductive Hormones and Puberty - Class X

Estrogens are produced primarily by the ovaries. They are released by the Graafian follicles on the ovaries and are also secreted by the corpus luteum after the egg has been released from the follicle and from the placenta. 

Estrogen is the female sex hormone which is secreted by developing follicles in the ovary. Secretion of gonadotropins during the follicular phase of ovarian cycle stimulate growth and development of follicles. These developing follicles secrete estrogen. Thus, the correct answer is option C.

There are two major female sex hormones: estrogen and progesterone. Both of these are steroid hormones. In women, most estradiol is released from the ovaries and adrenal glands. It is also released by the placenta during pregnancy.

The primary function of oestrogen is the development of the female body and secondary sexual characteristics. These include breasts, endometrium, regulation of the menstrual cycle etc. They are present in significantly higher amounts in women after menarche (onset of menstrual periods at puberty) until menopause (cessation of menstrual periods after completion of reproductive age). Hence, oestrogen is a feminizing hormone.

After ovulation, the ruptured Graafian follicle transforms into the corpus luteum, which acts as an endocrine gland by secreting progesterone and estrogen.

Oestrogens, in females, are produced primarily by the ovaries, and during pregnancy, the placenta. Follicle-stimulating hormone (FSH) stimulates the ovarian production of oestrogens by the granulosa cells of the ovarian follicles and corpora lutea. Synthesis of oestrogens starts in theca interna cells in the ovary, by the synthesis of androstenedione from cholesterol. 

Ovaries produce and release two groups of sex hormones progesterone and estrogen. 

Relaxin, HCG and placental lactogen are protein hormones having amino acids bonded together in a polypeptide chain. Estradiol is a steroid hormone and has three cyclohexyl rings and one cyclopentyl ring joined into a single structure. Thus, the correct answer is D.

Oestrogen is a steroid hormone which is secreted by females gonads. Oestrogen is the hormone which is responsible for the development of secondary sexual characteristics in the female at puberty. It causes the development of breasts, axial and pubic hair and fat distribution. It is also responsible for the maintenance and maturation of the sexual organs in the human body. The hormone also plays role in thickening of the endometrium and other aspects of menstrual cycle and pregnancy.

Estrogen is essential for development of secondary sex organs and external female sex characters like breasts, high pitch voice at puberty. The main function is the tissue growth and cell proliferation in specific areas of body. It promotes the development and maintenance of female reproductive structures. It assists in the control of fluid and electrolyte balance within the body, ensuring that our skin retains moisture. It prepares the follicle for the release of an egg. It controls the changes in our cervical mucus. It prepares our internal environment for fertility making it more sperm friendly.

The corpus luteum is a temporary endocrine structure that primarily secretes progesterone to maintain the uterine lining, but it also produces significant amounts of estrogen.

Luteinizing hormone (LH) triggers the process of ovulation and subsequently stimulates the transformation of the ruptured follicle into the corpus luteum.

There are two major female sex hormones as estrogen and progesterone. Both of these are steroid hormones and are produced by the ovaries.
Therefore, the correct answer is option D.

Estrogens are primary female sex hormones that serve in maturation and maintenance of sex organs, development of female secondary sexual characters and initiation of menstrual cycle. Likewise, progesterone prepares the body for pregnancy and maintain the uterus if pregnancy occurs. Along with estrogens, progesterone helps initiate menstrual cycle in girls entering the puberty. Both enzymes work synergistically. 

Estrogen is the female sex hormone. It is mainly secreted by the granulosa cells of the ovarian follicles (in ovary) under the influence of FSH. These hormones are also released by the corpus luteum (after the egg has been released from the follicle) and from the placenta. It is responsible for maintaining the secondary sexual characteristics in female. In males, it helps in the sperm maturation. It also thickens the uterine lining during the menstrual cycle for pregnancy. So, the correct option is A.

a) Thyroxine is a thyroid hormone which targets all tissues and stimulates metabolic rate, growth, and development. 

Graafian follicles are mature ovarian follicles found in the ovaries of mammals, including rabbits, where they develop before ovulation.

Osteoporosis (fragile or weak bones) is very common in women during their menopause because of the depletion of the oestrogen levels in their blood. Oestrogen is a sex hormone which is important for female bone health because it promotes the activity of osteoblasts, which are cells involved in the formation of bone. Thus, the correct option is D.

At puberty, hypothalamus releases gonadotrohphin releasing hormone (GnRH) which stimulates the anterior pituitary gland. the latter secrete the FSH/LH from the anterior pituitary gland.

FSH- Stimulate the growth of graffian follicle, maturation of ovum, secretion of estrogen by follicle cells. Estrogen, or oestrogen, is the primary female sex hormone. It is responsible for the development and regulation of the female reproductive system and secondary sex characteristics.

LH- The luteinising hormone stimulates release of ovum( ovulation), formation of corpus luteum in the empty follicle and secretion of progesterone from the corpus luteum. Progesterone suspends ovulation during pregnancy, maintains foetal connection with the uterine wall and controls development of foetus in the uterus. If fertilization fails, means no pregnancy so progesterone level decreases to restart the process of ovulation.

So, the correct answer is 'Progesterone and estrogen'.

Hormone therapy is indeed used to replace hormones that decline with age, and it has various clinical benefits. However, the reason provided does not fully explain the assertion, as the benefits are specific to managing symptoms rather than just the act of replacement.

The FSH stimulates the follicle cells to secrete estrogen a female sex organ.

Estrogen, or oestrogen, is the primary female sex hormone. It is responsible for the development and regulation of the female reproductive system and secondary sex characteristics. Estrogens are responsible for the development of female secondary sexual characteristics during puberty, including breast development, widening of the hips, and female fat distribution. Estrogen, in conjunction with growth hormone and its secretory product insulin-like growth factor 1  is critical in mediating breast development during puberty.

• Ovulation is the release of eggs from the ovaries. In humans, this event occurs when the ovarian follicles rupture and release the secondary oocyte ovarian cells.
  
• The process of ovulation is controlled by the hypothalamus of the brain and through the release of hormones secreted in the anterior lobe of the pituitary gland, luteinizing hormone (LH) and follicle-stimulating hormone (FSH).
• Hence Ovulation is controlled mainly by luteinizing hormone.
• So, the correct answer is 'Luteinizing hormone'.