Tag: zoology

Questions Related to zoology

Gestation period in human beings is about 

zoology menustral cycle in human parturition and lactation pregnancy and birth fertilization and post fertilization in humans

  1. 10 weeks

  2. 28 weeks

  3. 32 weeks

  4. 36 weeks

Show answer
Correct Option: D
Explanation:

Gestation (pregnancy) is completed in about 266 days from the mother's last menstruation. The gestation period of human beings is 270 days to 280 (approximately). It is usually about 266 days i.e., 36 weeks.

The process of delivery of the feotus is called 

zoology menustral cycle in human parturition and lactation pregnancy and birth fertilization and post fertilization in humans

  1. Parturition

  2. Implantation

  3. Fertilisation

  4. Lactation

  5. Ovulation

Show answer
Correct Option: A
Explanation:

Parturition can be defined as the act of expelling the full term young ones from the mother's uterus at the end of the gestation period. In other words, the process of delivery of the fetus is known as parturition.

Delivery of developed foetus is

zoology menustral cycle in human parturition and lactation pregnancy and birth fertilization and post fertilization in humans

  1. Ovulation

  2. Oviposition

  3. Parturition

  4. Abortion

Show answer
Correct Option: C
Explanation:

The delivery of the developed foetus after 9 months is known as parturition. Ovulation is the release of the secondary oocyte from the ovary. 

Oviposition is known as the egg-laying stage.
Abortion is the ending of the pregnancy before time. If it is abrupt then it is known as a miscarriage but if the abortion is surgical and through pills, it is known as induced abortion.
So, the correct option is 'Parturition'.

Thick yellow, high protein fluid produced by mammary glands of a woman during first $2-3$ days after child birth is

zoology menustral cycle in human parturition and lactation pregnancy and birth fertilization and post fertilization in humans

  1. Meconium

  2. Hymen

  3. Cumulus oophorus

  4. Colostrum

Show answer
Correct Option: D
Explanation:
The mammary glands undergo differentiation during pregnancy and start producing milk towards the end of pregnancy by the process called lactation.
The milk produced during the initial few days of lactation – colostrum. It is thick and yellow in colour. It contains several antibodies essential to develop resistance for new-borns.
so, the correct option is 'Colostrum'.

State whether the following statements are true or false.
Prolactin stimulates milk secretion and growth of breast.

zoology menustral cycle in human parturition and lactation pregnancy and birth fertilization and post fertilization in humans

  1. True

  2. False

Show answer
Correct Option: A
Explanation:
Prolactin regulates the growth of the mammary glands and formation of milk in them. Prolactin has a wide variety of effects. It stimulates the mammary glands to produce milk (lactation). Increased serum concentrations of prolactin during pregnancy cause enlargement of the mammary glands and prepare for milk production.
So, the correct option is 'True'.

Breast feeding suspends pregnancy due to

zoology menustral cycle in human parturition and lactation pregnancy and birth fertilization and post fertilization in humans

  1. Post pregnancy lower levels of FSH and LH

  2. Post pregnancy higher levels of FSH and LH which puts a negative check on ovulation

  3. Inhibiting the release of FSH by prolactin and thus countering the effects of FSH on the ovarian follicles

  4. Increasing the release of inhibin by prolactin and thus countering the effects of FSH on the ovarian follicles

Show answer
Correct Option: C
Explanation:

The hypothalamus secretes the Gonadotropin-releasing hormone which is responsible for menstruation sequence. The GnrRH repressed by the prolactin hormone, which encourages the production of milk. Without the GnRH release, the menstrual cycle wont begin a new event of pregnancy.

As long as prolactin level are high, GnRH generally won't be release. Now GnRH is responsible for the release of the follicular stimulating hormone. The hormone FSH is responsible for the formation of ovarian follicle. So, as GnRH is stopped there will be an inhibition in the release of FSH by prolactin and thus thus it counter the effects of FSH on the ovarian follicle. So, there will be a delay in ovulation that will automatically prevent pregnancy. 
So, the correct option is 'Inhibiting the release of FSH by prolactin and thus countering the effects of FSH on the ovarian follicle'.

Which of these is not an important component of the initiation of parturition in humans?

zoology menustral cycle in human parturition and lactation pregnancy and birth fertilization and post fertilization in humans

  1. Synthesis of prostaglandins

  2. Release of oxytocin

  3. Release of prolactin

  4. Increase in estrogen and progesterone ratio

Show answer
Correct Option: C
Explanation:

  • Parturition is a phenomenon of giving birth. It is a process of delivering a child from the womb to the outside. It is usually initiated by the release of oxytocin hormone. 
  • This hormone increases the contraction of uterine muscles. Prostaglandins are synthesized and released in response to the oxytocin hormone. Also, an increase in estrogen and progesterone ratio indicates the initiation of the parturition process. 
  • Prolactin hormones are released after the parturition in order to secrete the milk from the mammary gland.

Thus, the correct answer is 'Release of prolactin.'

Which of the following statement is incorrect regarding the parturition?

zoology menustral cycle in human parturition and lactation pregnancy and birth fertilization and post fertilization in humans

  1. The signals of parturition originate from fully developed foetus and ovary

  2. Relaxin hormine relaxes the pubic symphysis during parturition

  3. Thyroxine is a main parturition hormone

  4. HCG is responsible for labour pain

Show answer
Correct Option: C
Explanation:

Parturition is the process of giving birth to the child.

A)its signal starts from the mature fetus.
B)Relaxin hormone relaxes the pubic symphysis during parturition by softening and lightening pubic symphysis.
C)Oxytocin is the main parturition hormone.
D)HCG is responsible for labor pain.
So the correct option is 'Thyroxine is the main parturition hormone'.

Foetal ejection reflex triggers the release of 

zoology menustral cycle in human parturition and lactation pregnancy and birth fertilization and post fertilization in humans

  1. Prolactin by maternal pituitary

  2. Prolactin by foetal pituitary

  3. Oxytocin by foetal pituitary

  4. Oxytocin by maternal pituitary

Show answer
Correct Option: D

The haemoglobin of a human foetus

zoology menustral cycle in human parturition and lactation pregnancy and birth fertilization and post fertilization in humans

  1. Has a higher affinity for oxygen than that of an adult

  2. Has a lower affinity for oxygen than that of the adult

  3. Its affinity for oxygen is the same as that of an adult

  4. Has only $2$ protein subunits instead of $4$

Show answer
Correct Option: A
Explanation:
  • The oxygen is needed for aerobic respiration and diffuses from a region of high to low concentration from the mother's blood to the blood of the foetus. 
  • The haemoglobin of the foetus has a higher affinity for oxygen than that of adult haemoglobin and so the efficiency of exchange is increased

So, the correct answer is 'Has a higher affinity for oxygen than that of an adult'