Tag: ethology

Questions Related to ethology

Which of the following hormones stimulates the production of milk?

biology animal behaviour ethology natural selection coordination in human beings- chemical control endocrine system in humans

  1. LH

  2. Prolactin

  3. Oxytocin

  4. Progesterone

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Correct Option: B
Explanation:

Prolactin is the hormone that stimulates milk production. During pregnancy, prolactin stimulates growth of the breast, but high estrogen and progesterone secretion prevent milk production. After delivery, estrogen and progesterone levels drop, and prolactin stimulates the secretion of milk by alveolar cells in the breast.

Some hormones check the milk from being secreted by the mammary glands till the birth of young ones even though the glands are all prepared to do so. They are

biology animal behaviour ethology natural selection coordination in human beings- chemical control endocrine system in humans

  1. Progesteron and prolactin

  2. Prolactin and FSH

  3. Oestrogen and prolactin

  4. Oestrogen and progesteron

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Correct Option: A
Explanation:
Progesterone and prolactin check the milk from being secreted by the mammary glands till the birth of young ones even though the glands are all prepared to do so. Progesterone is a hormone released by the corpus luteum in the ovary. Changing progesterone levels can contribute to abnormal menstrual periods and menopausal symptoms. Prolactin is a hormone named originally after its function to promote milk production (lactation) in mammals in response to the suckling of young after birth. It has since been shown to have more than 300 functions in the body. These can be divided into a number of areas: reproductive, metabolic, regulation of fluids (osmoregulation), regulation of the immune system (immunoregulation) and behavioural functions.
At birth, prolactin levels remain high, while the delivery of the placenta results in a sudden drop in progesterone, oestrogen, and HPL levels.

Lemmings reduce their number by committing suicide every

biology animal behaviour ethology natural selection coordination in human beings- chemical control endocrine system in humans

  1. Eight years

  2. Alternate years

  3. Four years

  4. Two years

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Correct Option: C
Explanation:

Lemmings reduce their number by committing suicide every 4 years. It has been regarded as a collective suicide, conscious or involuntary, caused by overpopulation. In reality, being solitary rodents by nature, when the population booms, the stronger lemmings drive the weaker and younger ones off long before the food is depleted.

Therefore, the correct answer is option (C).

The unit of natural selection is

biology selection and evolution ethology animal behaviour natural selection

  1. An individual

  2. A species

  3. A genus

  4. A population

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Correct Option: A

The idea of natural selection as the fundamental process of evolutionary changes was reached by:

biology selection and evolution ethology animal behaviour natural selection

  1. Charles Darwin and Alfred Russel Wallace in 1900

  2. Charles Darwin in 1866

  3. Alfred Russel Wallace in 1901

  4. Charles Darwin and Alfred Russel Wallace in 1859

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Correct Option: D

Identify the true statement:

biology selection and evolution ethology animal behaviour natural selection

  1. Mutations are adaptive and occur according to the changes in the environment.

  2. Genetic drift is the random fluctuations in the allele frequencies in large population.

  3. Natural selection is the difference in reproduction that causes difference in the contribution of alleles of next generation.

  4. Mutations are directional and occurs in the individuals of a population.

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Correct Option: C

Which is known as "The living laboratory of evolution"?

biology selection and evolution ethology animal behaviour natural selection

  1. Galapagos islands

  2. Western Ghats

  3. Mediterranean sea

  4. Atlantic forest

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Correct Option: A

Natural selection means _________________.

biology selection and evolution ethology animal behaviour natural selection

  1. Nature selects desirable characters

  2. Nature rejects undesirable characters

  3. Nature reacts with an organism

  4. a, b

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Correct Option: A

The modern synthetic theory of evolutions\assumes a positive role of which of the following in evolution?
a. Natural selection
b. Acquired characters
c. Artificial selection
d. Mutations.

biology selection and evolution ethology animal behaviour natural selection

  1. $1$ and $2$

  2. $1$ and $3$

  3. $2, 3$ and $4$

  4. $1$ and $4$

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Correct Option: A

State whether the following statements are true or false .
Guttation takes place through specialised pores called lenticels.

biology selection and evolution ethology animal behaviour natural selection

  1. True

  2. False

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Correct Option: B
Explanation:

Guttation is a process of oozing out of the xylem sap on the margin of the leaves through specialized openings called hydathodes. Guttation is also known as bleeding of the leaf.

So, the given statement is false.