MECEE-BL Entrance Botany Questions with Answers

In angiosperms the endosperm is typically

Answer: triploid

A mature embryo sac of a typical angiosperm is

Answer: 7-celled and 8-nucleate

The nutritive layer of the anther wall that nourishes developing pollen grains is the

Answer: tapetum

If producers in a grassland fix 10000 J of energy, by the ten percent law the secondary consumers receive about

Answer: 100 J

The pioneer organisms in primary succession on bare rock are

Answer: lichens

Large air cavities (aerenchyma) in stems and roots are an adaptation of

Answer: hydrophytes

Crossing over takes place during which stage of meiosis?

Answer: Pachytene of prophase I

A diploid cell with 46 chromosomes undergoes meiosis. Each daughter cell will have

Answer: 23 chromosomes

A plant cell has 2n = 14. The number of chromosomes present in the cell during anaphase of mitosis is

Answer: 28

The phenotypic ratio of the F2 generation of a monohybrid cross showing complete dominance is

Answer: 3:1

A cross between an individual of unknown genotype and a homozygous recessive individual is called

Answer: a test cross

A heterozygous tall plant (Tt) is crossed with a dwarf plant (tt). The ratio of tall to dwarf offspring is expected to be

Answer: 1:1

The tissue that conducts water and minerals upward in plants is

Answer: xylem

Increase in the girth of a dicot stem is due to the activity of

Answer: vascular cambium

A stem transverse section shows vascular bundles arranged in a ring, conjoint, collateral and open. The stem is of a

Answer: dicot

The light reaction of photosynthesis takes place in the

Answer: thylakoid membranes of grana

The net gain of ATP from one glucose molecule in glycolysis is

Answer: 2

In photosynthesis, the oxygen released comes from

Answer: water

The hormone that causes ripening of fruits is

Answer: ethylene

During drought a plant closes its stomata. The hormone responsible is

Answer: abscisic acid

Transpiration mainly occurs through

Answer: stomata

The monomers of proteins are

Answer: amino acids

The storage polysaccharide of animals is

Answer: glycogen

The genetic material of Tobacco Mosaic Virus is

Answer: single-stranded RNA

A Gram-positive bacterium appears _____ after Gram staining.

Answer: purple

The organelle called the powerhouse of the cell is the

Answer: mitochondrion

The fluid mosaic model of the plasma membrane was proposed by

Answer: Singer and Nicolson

Whole plants can be regenerated from a single cell in tissue culture because of

Answer: totipotency

Bt cotton is resistant to

Answer: bollworm

Reproduction by conjugation is common in the green alga

Answer: Spirogyra

The cell wall of fungi is made of

Answer: chitin

In bryophytes the dominant, independent phase of the life cycle is the

Answer: gametophyte

The gametophyte of a fern is called

Answer: prothallus

Gymnosperms are called so because they

Answer: have naked seeds

A lichen is a symbiotic association between

Answer: an alga or cyanobacterium and a fungus

The dominant tree of the tropical forests of the Nepal Terai is

Answer: Shorea robusta

In a DNA molecule, adenine makes up 30 percent of the bases. The percentage of guanine is

Answer: 20

Doubling of chromosome sets (polyploidy) in plants can be induced artificially by

Answer: colchicine

Crossing over exchanges segments between

Answer: non-sister chromatids of homologous chromosomes

Root nodules of leguminous plants contain the nitrogen-fixing biofertilizer

Answer: Rhizobium