Question
Which element is responsible for causing soil salinity? At what concentration does the soil become saline?
✓
Answer
Minerals are responsible for causing soil salinity. Following are some of the cause for increase in soil salinity:
- High level of salt in soil.
- Water table movement because of landscape features.
- Human activities; like clearing of land and excess use of synthetic fertilizers.
- Salt runoff from streets can happen in cold climates because salt is applied on road to prevent snow accumulation.
Need a full question paper?
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
Explore more
Similar questions
What essential features must be present in a cloning vector?
Distinguish between asexual and sexual reproduction. Why is vegetative reproduction also considered as a type of asexual reproduction?
You are given a red flower–bearing pea plant and a red flower–bearing snapdragon plant. How would you find the genotypes of these two plants with respect to the colour of the flower? Explain with the help of crosses. Comment upon the pattern of inheritance seen in these two plants.
Fill in the blanks,
|
Species A
|
Species B
|
Type of Interaction
|
Example
|
|
+
+
+
|
-
+
_____
|
_____
_____
Commensalism
|
_____
_____
_____
|
With the help of a diagram explain the structure of DNA.
- Identify the parts labelled A, B and C in the diagram given.
- Draw a labelled diagram of a human blastocyst.
- What is parturition and is it induced at the end of pregnancy in a human female?
- How do organic farmers control pests? Give two examples.
- State the difference in their approach from that of conventional pest control methods.
During the biology class on theories of evolution, the teacher was telling about Lamarckism. Katy was confused after listening to it and went to her teacher to clear her doubts. She asked if characters can be passed to generations, then why she does not have the tatoo that her mother has on her arm. The teacher smiled and told Katy that this is the reason why Lamarck's theory was rejected. The teacher explained her the other theories as well.
- Name the book in which Lamarckism was explained.
- What are the three factors of this theory?
- What are the other theories of evolution?
- What are the values shown by teacher?
With a suitable diagram, describe the organisation of mammary gland.
What is Down’s syndrome? Give its symptoms and cause. Why is it that the chances of having a child with Down’s syndrome increases if the age of the mother exceeds forty years?