The technique used to study the internal structures of cells using electron beams is: MCQ with Answer and Explanation

Explanation:
The stratospheric ozone layer acts as a vital shield, absorbing the majority of the sun's harmful ultraviolet (UV-B and UV-C) radiation, protecting life on Earth. Greenhouse gases (like CO2, methane, water vapor) absorb and re-emit infrared radiation, trapping heat in the troposphere and maintaining Earth's temperature (the greenhouse effect). Acid rain, containing sulfuric and nitric acids, is highly detrimental; it leaches essential nutrients from the soil, releases toxic aluminum, and damages plant life, reducing soil fertility. Thus, statements 1 and 2 are correct.

Explanation:
The midbrain (mesencephalon) is the uppermost part of the brainstem. Its dorsal surface features four rounded elevations called the corpora quadrigemina (meaning 'four bodies'). These consist of two upper, larger swellings called the superior colliculi, which are reflex centers for visual movements (like tracking moving objects), and two lower, smaller swellings called the inferior colliculi, which are part of the auditory pathway and relay sound information to the thalamus.

Explanation:
Glyoxysomes are specialized peroxisomes found in the fat-storing cotyledons of germinating seeds. They contain enzymes for the beta-oxidation of fatty acids and the glyoxylate cycle, which converts stored lipids into carbohydrates (gluconeogenesis) to nourish the growing seedling. This metabolic pathway is absent in animal cells. Exam tip: Glyoxysomes eventually transform into chloroplasts as the plant matures.