Assertion (A): A person goes to high altitude and experiences 'altitude sickness' with symptoms like breathing difficulty and heart palpitations.
Reason (R): Due to low atmospheric pressure at high altitude, the body does not get sufficient oxygen.
In the light of the above statements, choose the correct answer from the options given below.

NEET-2021 [Organisms-and-Populations] [class-xii ]

• Both (A) and (R) are true and (R) is the correct explanation of (A)
• Both (A) and (R) are true but (R) is not the correct explanation of (A)
• (A) is true but (R) is false
• (A) is false but (R) is true
Correct Option: A  [ Both (A) and (R) are true and (R) is the correct explanation of (A) ]

Remark:

Match the items in Column-I with those in Column-II :

NEET-(Oct)2020 [Organisms-and-Populations] [class-xii ]

• (A)-(IV), (B)-(II), (C)-(I), (D)-(III)
• (A)-(III), (B)-(II), (C)-(IV), (D)-(I)
• (A)-(II), (B)-(I), (C)-(III), (D)-(IV)
• (A)-(I), (B)-(III), (C)-(IV), (D)-(II)
Correct Option: B  [ (A)-(III), (B)-(II), (C)-(IV), (D)-(I) ]

Remark:

The impact of immigration on population density is:

NEET-(Oct)2020 [Organisms-and-Populations] [class-xii ]

• Negative
• Both positive and negative
• Neutralized by natality
• Positive
Correct Option: D  [ Positive ]

Remark:

According to Alexander von Humboldt:

NEET-(Oct)2020 [Organisms-and-Populations] [class-xii ]

• Species richness decreases with increasing area of exploration
• Species richness increases with increasing area, but only up to limit
• There is no relationship between species richness and area explored.
• Species richness goes on increasing with increasing area of exploration
Correct Option: B  [ Species richness increases with increasing area, but only up to limit ]

Remark:

Which of the following is not an attribute of a population?

NEET-(Sept)2020 [Organisms-and-Populations] [class-xii ]

• Sex ratio
• Natality
• Mortality
• Species interaction
Correct Option: D  [ Species interaction ]

Remark:

Secondary metabolites such as nicotine, strychnine and caffeine are produced by plants for their:

NEET-(Sept)2020 [Organisms-and-Populations] [class-xii ]

• Nutritive value
• Growth response
• Defence action
• Effect on reproduction
Correct Option: C  [ Defence action ]

Remark:

Pinus seed cannot germinate and establish without fungal association. This is because:

NEET-2019 [Organisms-and-Populations] [class-xii ]

• it has obligate association with mycorrhizae.
• its embryo is immature
• it has very hard seed coat.
• its seeds contain inhibitors that prevent germination.
Correct Option: A  [ it has obligate association with mycorrhizae. ]

Remark:

Match Column - I with Column - II.

NEET-2019 [Organisms-and-Populations] [class-xii ]

• (A)-(I), (B)-(II), (C)-(III), (D)-(IV)
• (A)-(III), (B)-(II), (C)-(I), (D)-(IV)
• (A)-(II), (B)-(I), (C)-(III), (D)-(IV)
• (A)-(II), (B)-(III), (C)-(IV), (D)-(I)
Correct Option: D  [ (A)-(II), (B)-(III), (C)-(IV), (D)-(I) ]

Remark: