Reproductive system

Question 1

What is mitosis

Answer 1

It is a type of cell division which results in two daughter cells having the same number and kind of chromosomes as the parent nucleus

It is necessary fro growth and tissue repair

Question 2

What is meiosis

Answer 2

It is a type of cell division for producing gametes which are haploid sex cells

Here, each cell divides twice into 4 daughter cells. This is different to mitosis as the daughter cells aren’t the same as the parent cells due to the idea of crossing over of the chromosomes

Question 3

What is interphase

Answer 3

Duplicating chromatids to get a chromosome at 1 centromere (2 chromatids at 1 centromere), compared to just 1 chromatid at 1 centromere previously

Question 4

What is the approach which is common in both mitosis and meiosis

Answer 4

PMAT (Prophase, metaphase, anaphase, telophase)

However, in meiosis, pmat happens twice whereas in mitosis it only happens once

Question 5

Explain the process of prophase in mitosis

Answer 5

Chromosomes in the cell nucleus start to condense together in preparation for cell division

Nucleus is still available

Mitotic spindles begin to appear

Question 6

Explain the process of metaphase in mitosis

Answer 6

Nucleus has been disassembled

Chromosomes are lined up singularly(i think) singleline

Question 7

Explain the process of anaphase in mitosis

Answer 7

Chromosomes separate and move towards poles of the cell, with assistance from the mitotic spindles

Question 8

Explain the process of telophase in mitosis

Answer 8

New nuclei starts to form around the separated chromosomes

Each new daughter cell is a diploid cell containing 46 chromosomes each

Question 9

What is cytokineses

Answer 9

Final separation where cytoplasm is severed to leave two identical cells

Question 10

Explain the process of Prophase 1 in meiosis

Answer 10

Same process as mitosis prophase, however CROSSING OVER can occur, where random sharing of genes can occur between chromosomes –> increased genetic variation

Question 11

Explain the process of metaphase 1 in meiosis

Answer 11

Same process as mitosis however some chromosomes may have crossed over.

Nucleus has been disassembled and the chromosomes are lined up in the middle of the cell with mitotic spindles connected

ADditionally, the chromosomes here are lined up in their homologus pairs –> when separation occurs it splits into 23

Question 12

Explain the process of anaphase 1 in meiosis

Answer 12

Same process as anaphase in mitosis

Chromosomes separate and move towards the poles of the cell

Question 13

Explain the process of telophase 1 in meiosis

Answer 13

Same as mitosis telophase

New nuclei starts to form around separated chromosomes

Question 14

Explain the function of cytokinesis in meiosis

Answer 14

It separates where cytoplasm is severed to leave remaining two cells

Question 15

Explain the process of prophase 2 in meiosis

Answer 15

Same function as prophase 1 but no crossing over

Question 16

Explain the process of metaphase 2 in meiosis

Answer 16

Chromosomes don’t line up in pairs but are single file

As a result, whe they divide they become haploid (23 chromosomes) rather than diploid (46 chromosomes)

Question 17

Explain the process of anaphase 2 in meiosis

Answer 17

chromatids (half) are pulled away fro centre of cells not the chromosomes (full)

Question 18

Explain the process of telophase 2 in meiosis

Answer 18

Four haploid daughter cells are formed

Question 19

Explain the process of the second cytokinesis in meiosis

Answer 19

Leaves remaining 4 haploid daughter cells

Question 20

What are the key organs in the female reproductive system

Answer 20

Vagina, cervix, cervical canal, uterus, fallopian tube, fimbriae and ovary

Question 21

What is the function of the vagina

Answer 21

It provides a passageway for blood and mucosal tissue from the uterus to leave the body during a menstrual period. It’s where the penis is inserted during vaginal sex and it holds sperm until they pass into the uterus. It provides a passageway for childbirth.

Question 22

What is the function of the cervix

Answer 22

The lower, narrow end of the uterus (womb) that connects the uterus to the vagina (birth canal). The cervix allows fluids, such as menstrual blood, to pass from the uterus into the vagina. It also widens during the birth of a baby.

Question 23

What is the function of the cervical canal

Answer 23

It allows blood from a menstrual period and a baby (fetus) to pass from the womb into the vagina. The sperm travel from the vagina up the cervical canal into the uterine cavity, then into the fallopian tubes to fertilize the egg.

Question 24

What is the function of the uterus

Answer 24

The uterus functions by nurturing the fertilized ovum, which passes through the fallopian tube. The ovum then implants into the endometrium, where it receives nourishment from blood vessels, which are exclusively developed for this purpose.

Question 25

What is the function of the fallopian tube

Answer 25

Your fallopian tubes are an important passageway for an egg and a sperm to meet and for a fertilized egg (embryo) to make its way to your uterus. Successful fertilisation normally occurs in first third of the fallopian tube

Question 26

What is the function of the fimbriae

Answer 26

Fimbriae are finger-like projections on the ends of your fallopian tubes closest to your ovaries. Each month, your fimbriae catch the egg that one of your ovaries releases during ovulation. Your fimbriae then sweep the egg (ovum) into the fallopian tube where the egg can be fertilized.

Question 27

What is the function of the ovary

Answer 27

The ovaries are small, oval-shaped glands located on either side of your uterus. They produce and store your eggs (also called ovum) and make hormones that control your menstrual cycle and pregnancy. During ovulation, one of your ovaries releases an egg

Question 28

What are the important organs in the male reproductive system

Answer 28

Scrotum, teesticle, vas deferens, epididymis, cowpers gland, ejaculatory gland, seminal vesicle, prostate, urethra

Question 29

What is the function of the scrotum

Answer 29

he scrotum is responsible for protecting the testes. It helps with the thermoregulation of the testicles. It keeps the temperature of the testis several degrees below the average body temperature, which is an essential factor for sperm production.

Question 30

What is the function of the testicle

Answer 30

he scrotum is responsible for protecting the testes. It helps with the thermoregulation of the testicles. It keeps the temperature of the testis several degrees below the average body temperature, which is an essential factor for sperm production.

Question 31

What is the function of the vas deferens

Answer 31

The vas deferens is a long, muscular tube that travels from the epididymis into the pelvic cavity, just behind the urinary bladder. The vas deferens transports mature sperm to the urethra in preparation for ejaculation.

Question 32

What is the function of the epididymis

Answer 32

unction of the epididymis is to transport sperm from the rete testes to the vas deferens

Question 33

What is the function of the cowpers gland

Answer 33

Cowper's glands are pea sized glands present inferior to the prostate gland in the male reproductive system. They produce thick clear mucus prior to ejaculation that drains into the spongy urethra. Mucous (released pre ejaculation), lubricate urethra and end of penis to prevent damage to sperm. Alkaline fluid, neutralises acidity of urethra and decreases acidity of vagina to protect sperm

Question 34

What is the function of the ejaculatory duct

Answer 34

The ejaculatory ducts are a part of the male anatomy that allows the flow of sperm from the testes through the reproductive system and eventually out through the urethra.

Question 35

What is the function of the seminal vesicle

Answer 35

The seminal vesicles are two small glands that store and produce the majority of the fluid that makes up semen. During ejaculation, the fluid from the seminal vesicles is expelled into the ejaculatory duct where it can then move on to mix with sperm and other reproductive fluids. Prostaglandin, stimulates motility of sperm Fructose iis a nutrient source for the sperm Clotting agents coagulates semen after ejaculation

Question 36

What is the function of the prostate

Answer 36

The prostate's most important function is the production of a fluid that, together with sperm cells from the testicles and fluids from other glands, makes up semen. The muscles of the prostate also ensure that the semen is forcefully pressed into the urethra and then expelled outwards during ejaculation. Citric acid, used by sperm in ATP production Proteolytic enzymes eventually breakdown clotting agents --> decoagulates for it to flow in female reproductive system

Question 37

What is the function of the urethra

Answer 37

This tube allows urine and sperm to pass outside the body.

Question 38

what is spermatogenesis

Answer 38

Spermatogenesis is the process of sperm cell development. Rounded immature sperm cells undergo successive mitotic and meiotic divisions (spermatocytogenesis) and a metamorphic change (spermiogenesis) to produce spermatozoa.

Question 39

Explain process of spermatogenesis

Answer 39

The germ cell (spermatogonium) undergoes mitotic division, and produces 2 daughter cells (2n). 1 of the daughter cells then becomes the primary spermatocyte (2n) The spermatocyte then undergoes first meiotic division to form 2 secondary spermatocytes (n). These then undergo second meiotic division to form 4 spermatids (n) They then go through spermiogenesis. which allows them to develop into sperm cells (involves forming their golgi body, tails, maturation, acrosomes etc) After spermiogenesis, it still isnt motile, and is thus released into lumen of seminferous tubules to epididymis to gain motility

Question 40

Explain the process of oogenesis

Answer 40

There are around 5 million oogonia before birth (2nd trimester). At birth, there are around 400 000 primordial follicles (2n). These contain primary oocytes which are paused at prophase 1 until meiosis 1 is finished It then develops into the primary follicle (2n), whhich still contains the paused primary oocyte, with layers of granulosa cells and the zona pellucida. This then, develops into the secondary follicle, where there is now fluid filled spaces inside the follicle called the the antrum. Only around 400 of these secondary follicles fully develop in a lifetime. This is now a mature/graafian follicle (2n), which still contains the primary oocyte. Just before ovulation the oocyte completes Meiosis 1 and pauses during early meiosis 2. Meiosis will be completed if fertilisation occurs. Ovulation triggered by peak in LH from the pituitary causes the secondary oocyte (n) to leave the mature follicle, and the granulosa cells form the corpus luteum, and it completes meiosis. The corpus luteum secretes progesterone and a small amount of estrogen to be used during the menstrual cycle

Question 41

Explain the hormones in males before puberty

Answer 41

Testosterone and inhibin inhibit GnRH (secreted by immature hypothalamus) and LH and FSH secretion by the anterior pituitary gland

Question 41

Explain the hormones in males after puberty

Answer 41

Begins at age 12-14. Hypothalamus maturation reduces sensitivity to testosterone and inhibin. GnRH secretion increases, thuse increasing LH and FSH. This results in spermatogenesis, enlargement of reproductive organs and development of secondary male characteristics

Question 42

Explain the hormones in females before puberty

Answer 42

Estrogen and progesterone provide a negative feedback. Thus inhbiting GnRH production, and causing low LH and FSH

Question 43

Explain the hormones in females after puberty

Answer 43

Begins 11-13 years old (menarche). Maturation of hypohalamus --> high GnRH, high LH and FSH, decreased negative feedback of estrogen and progesterone, estrogen production is increased by developing follicle Enlargement of reproductive organs and development of secondary female characteristics