NEET Test 161

Brown algae are the members of the class Phaeophyceae. Their chromatophores are ellipsoidal or discoid. They contain chlorophyll a, chic, (i- and c- carotenes) and xanthophyll pigments (e.g. lutein, flavoxanthin, violaxanthin). They also contain a large amount of brown pigment - fucoxanthin which masks the green colour of chlorophyll pigment. This gives a characteristic brown colour to these plants, that's why the name brown algae. The non-motile resting spores of Chlamydomonas contain a red pigment called hematochrome. Phycocyanin and phycoerythrin are water-soluble pigments found in red and blue-green algae.

Matthias Schleiden was a German botanist who observed the different types of cells present in plant tissue of various types of plants in 1838. Schleiden and Schwann together formulated the cell theory. Schleiden defined the cell as the basic unit of plant structure, and a year later Schwann defined the cell as the basic unit of animal structure.

Heat ′Q′ is a path-dependent function, hence its exact differentiation is not possible, however, internal energy, entropy, and Gibbs free energy are state functions, hence can be differentiated exactly.

In the nucleus of each cell, the DNA molecule is packaged into thread-like structures called chromosomes. Each chromosome is made up of DNA tightly coiled many times around proteins called histones that support its structure.

The simplest situation of dominant and recessive alleles is if one allele makes a broken protein. When this happens, the working protein is usually dominant. The broken protein doesn't do anything, so the working protein wins out.

Pollination is the process of transfer of pollen grain from anther to stigma of the female reproductive organ. If the transfer is to a different flower of different plant then it is considered to be cross pollination. It is also called xenogamy.

If the transfer of pollen grain is between the neighboring flowers of the same plant then it is called geitonogamy.

Self-pollination and fertilization occurring in a closed flower are termed cleistogamy. Herkogamy is a technique to ensure cross-pollination using a mechanical barrier.

Heat of reaction is an extensive property.

Hence, on change of amount/concentration of reactants heat of reaction changes.