Attempt giving a clear definition of the term species
Solution and Explanation
Top Questions on Evolution
- Define Adaptive Radiation and give examples like Darwin's Finches.
- HBSE Class 12 - 2026
- Biology
- Evolution
- On which island group did Darwin observe finches?
ডারউইন কোনটিকে 'প্রকৃতির খেলা' রূপে আখ্যায়িত করেছিলেন?
সমবয়ী অঙ্গের বিবর্তনকে বলা হয়
একটি মৌমাছি কীভাবে শ্রমিক মৌমাছি অন্য শ্রমিক মৌমাছিদের খাদ্য উৎসের বার্তা দেয় ব্যাখ্যা করো। ডারউইনের অভিব্যক্তি সংক্রান্ত তত্ত্বের তিনটি বিষয় ব্যাখ্যা করো — প্রাকৃতিক নির্বাচন, অস্তিত্বের জন্য সংগ্রাম, প্রকরণের উৎপত্তি।
Questions Asked in CBSE CLASS XII exam
- Find the general solution of the differential equation \[ y\log y\,\frac{dx}{dy}+x=\frac{2}{y}. \]
- CBSE CLASS XII - 2026
- Differential Equations
- A square loop of side 0.50 m is placed in a uniform magnetic field of 0.4 T perpendicular to the plane of the loop. The loop is rotated through an angle of 60° in 0.2 s. The value of emf induced in the loop will be:
- CBSE CLASS XII - 2026
- Electromagnetic induction
A racing track is built around an elliptical ground whose equation is given by \[ 9x^2 + 16y^2 = 144 \] The width of the track is \(3\) m as shown. Based on the given information answer the following:
(i) Express \(y\) as a function of \(x\) from the given equation of ellipse.
(ii) Integrate the function obtained in (i) with respect to \(x\).
(iii)(a) Find the area of the region enclosed within the elliptical ground excluding the track using integration.
OR
(iii)(b) Write the coordinates of the points \(P\) and \(Q\) where the outer edge of the track cuts \(x\)-axis and \(y\)-axis in first quadrant and find the area of triangle formed by points \(P,O,Q\).
- CBSE CLASS XII - 2026
- Integration
- Consider a cylindrical conductor of length \( l \) and area of cross-section \( A \). Current \( I \) is maintained in the conductor and electrons drift with velocity \( \vec{v}_d \, (|\vec{v}_d| = \frac{eE}{m} \tau) \), where symbols have their usual meanings. Show that the conductivity of the material of the conductor is given by \[ \sigma = \frac{n e^2 \tau}{m}. \]
- CBSE CLASS XII - 2026
- Current Density
- The painting Hazrat Nizamuddin Auliya and Amir Khusro belongs to which sub-school of Deccan Miniature?
- CBSE CLASS XII - 2026
- Indian Miniature Paintings and Museums
Concepts Used:
Hardy-Weinberg Principle
Hardy Weinberg Law:
In a considerable size, random-mating population, the genotype and allele frequencies remain constant in the absence of any evolutionary influences from one generation to another. Influences include a choice of mate, natural selection, genetic drift, mutation, sexual selection, gene flow, genetic hitchhiking, founder effect, meiotic drive, population bottleneck, inbreeding, and assortative mating.
Assumptions for the Hardy Weinberg Principle
Following are a few assumptions for the law:
- Only sexual reproduction can take place.
- The mating process is random.
- The size of the population is indefinitely large.
- Entities are diploid.
- Generations do not overlap.
- Equality of allele frequencies in terms of sexes.
- No gene flow, selection, mutation, migration, or admixture.