Tag: zoology

Questions Related to zoology

If a couple has four girls ,the probability of fifth child being male is _________.

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

  1. $50\%$

  2. $25\%$

  3. $75\%$

  4. $100\%$

Show answer
Correct Option: A
Explanation:

The gender of the consecutive children does not depend on each other. So, every time the couple has a kid, there is equal chances of them having a girl or a boy. Therefore, the probability would be 50% reasonably. 

In human beings, pregnancy lasts for $9$ months. The gestation period of dog, elephant, cat and cow is given. Which of the following is wrong match?

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

  1. Animal - Dog, Gestation period - $60-65$ days

  2. Animal- Elephant, Gestation period - $607-641$ days

  3. Animal - Cat, Gestation period - $52-65$ days

  4. Animal - Cow, Gestation period - $330-345$ days

Show answer
Correct Option: A
Explanation:

Gestation length varies by age of dam, breed, and sex of the calf. Gestation length ranges from 279 to 287 days. For most breeds, 283 days is common. In dogs, the entire gestation period is approximately nine weeks, or 63 days, although it can range from 58 to 68 days. Cat pregnancy normally lasts between 63 to 67 days, but it can be tough to know exactly how long a cat is pregnant for. The cat gestation period can vary from as short as 61 days to as long as 72 days. so, 'the correct option is-Animal - Cow, Gestation period - 330−345 days'

In which month, can the foetal movements be observed?

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

  1. $1^{st}$

  2. $5^{th}$

  3. $3^{rd}$

  4. $4^{th}$

Show answer
Correct Option: B
Explanation:
During the first pregnancy, it may not feel that the baby will move until closer to 25 weeks. By the second pregnancy, some women start to feel movements as early as 13 weeks. The first kicking activity is seen in the 5th month.
So, the correct option is '5th'. 

Find the correct statements.
a. By the end of $2^{nd}$ month of pregnancy, foetus limbs and digits develop
b. By the end of $1^{st}$ trimester, most of the major organs are formed in basic form.
c. Signal for parturition originates from fully developed foetus and placenta
d. Lactation starts after the end of pregnancy period

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

  1. a & c

  2. c & d

  3. b, c & d

  4. a, b, c & d

Show answer
Correct Option: D
Explanation:

It has been observed that by the end of the second month of pregnancy period, the foetus develops limbs and digits. Also, by the end of the first trimester (12 weeks), most of the major organs are developed, for instance, the limbs and external genital organs. The signals for parturition derives from the fully developed foetus and the placenta that further leads to mild uterine contraction referred to as foetal ejection reflex. By the end of pregnancy, the mammary glands initiate producing milk by the lactation process. 

So, the correct answer is option D, a, b, c & d. 

The process of releasing the ripe female gamete(ovum) from the ovary is called?

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

  1. Parturition

  2. Ovulation

  3. Fertilisation

  4. Implantion

Show answer
Correct Option: A

Milk ejection hormone in a lactating mother is?

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

  1. Prolactin

  2. Oxytocin

  3. Progesterone

  4. Estrogen

Show answer
Correct Option: A
Explanation:

Lactation is the method of synthesizing and secreting milk from the postpartum female breast mammary glands in reaction to a child sucking in the nipple. Mammary glands, which are enclosed in the breasts, produce the milk. The mammary gland consists of milk-carrying lactiferous ducts that grow and branch widely in reaction to estrogen, growth hormone, cortisol and prolactin during pregnancy.The prolactin of the pituitary hormone is extremely influential in establishing and maintaining the supply of breast milk. It is also essential for mobilizing breast milk maternal micro vitamins and minerals.

Foetal ejection reflex in human female is induced by?

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

  1. Differentiation of mammary gland

  2. Pressure exerted by amniotic fluid

  3. Release of oxytocin from pituitary

  4. Fully developed foetus and placenta

Show answer
Correct Option: D
Explanation:
  • When a woman is in a lithotomy or semi-sitting position, the Foetal Ejection Reflux is impaired and the increased pain caused by the sacrum’s inability to move as the baby descends can be intolerable
  • Foetal ejection reflex in human female is induced by fully developed foetus and placenta. so, option D is correct

Gestation period of rabbit is

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

  1. 18 - 20 days

  2. 28 - 32 days

  3. 48 - 50 days

  4. 60 - 70 days

Show answer
Correct Option: B
Explanation:

Gestation period is the time taken for embryo development after fertilization of egg in the female animal. 

In humans the gestation period is approximately 38 weeks. The gestation periods of chimpanzees (237 days), gorilla (257 days) and orangutan (260 days) indicate that the approximate nine-month gestation period predates the emergence of human beings as a species. 
The gestation periods of other animal reveals, that the length of the gestation period is largely a matter of the animal specie's size. Asian elephants have a gestation period of 645 days and African elephants 640 days. Dogs and other canines have a gestation period of about 60, which is also the period for cats. Even within the species of apes and monkeys gestation period seem to be a matter of size. For Rhesus monkeys it is 164 days and baboons 187 days. 
For small animals such as rabbits the period is about 33 days and for mice about 20 days. Thus, it appears that it takes a longer time for a big animal such an elephant to grow a baby than for a smaller animals, such as a mouse.

Monoestrous cycle animals may have

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

  1. One ovulation each month

  2. One egg

  3. One breeding season in a year

  4. One menses each month

Show answer
Correct Option: C
Explanation:

Estrous cycle, or oestrous cycle, is the reproductive cycle found in most mammalian placental females, whereby there are recurring periods when the female is fertile and sexually receptive (estrus) interrupted by periods in which the female is not fertile and not sexually receptive (anestrus). 

Animals that have estrous cycles reabsorb the endometrium (inner membrane of the mammalian uterus) if conception does not occur during that cycle. The estrous cycle is contrasted with the menstrual cycle in which the endometrium is shed through menstruation when pregnancy does not occur and in which the female may be sexually receptive at any time during the cycle. 
There are many variations among animals in terms of their estrous cycles. Some may undergo estrous only one time a year during a particular season (monoestrous example white-tailed deer, foxes), while others may undergo a succession of cycles (polyestrous) during a certain time of the year if they do not become pregnant (horses, sheep), and others may undergo cycles throughout the whole year (mice, cows, pigs).

Gestation period is minimum in which of the following?

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

  1. Rabbit

  2. Man

  3. Elephant

  4. Mouse

Show answer
Correct Option: D
Explanation:

Gestation period is the time taken for embryo development after fertilization of egg in the female animal. In humans the gestation period is approximately 38 weeks. 

The gestation periods of chimpanzees (237 days), gorilla (257 days) and orangutan (260 days) indicate that the approximate nine-month gestation period predates the emergence of human beings as a species. The gestation periods of other animal reveals that the length of the gestation period is largely a matter of the animal specie's size. 
Asian elephants have a gestation period of 645 days and African elephants 640 days. Dogs and other canines have a gestation period of about 60, which is also the period for cats. Even within the species of apes and monkeys gestation period seem to be a matter of size. For Rhesus monkeys it is 164 days and baboons 187 days. 

For small animals, such as rabbits the period is about 33 days and for mice about 20 days. Thus, it appears that it takes a longer time for a big animal such an elephant to grow a baby than for a smaller animal such as a mouse.