Carotenes are essential photosynthetic accessory pigments that strongly absorb blue and green light while primarily reflecting orange light, giving fruits like carrots their distinct color.
87. Double fertilization is a unique feature of:
(A) Bryophytes
(B) Algae
(C) Angiosperms
(D) Gymnosperms
Answer:
(C) Angiosperms
Explanation:
Double fertilization—a complex process where one sperm cell fertilizes the egg to form a zygote, and a second sperm cell fuses with binucleate central cells to form the endosperm—occurs exclusively in angiosperms (flowering plants).
88. Back cross is a cross between:
(A)
(B) * Recessive
(C) Dominant
(D) Any parent
Answer:
(D) Any parent
Explanation:
In classical genetics, a back cross specifically involves mating a first-generation () hybrid organism back with any one of its original parental strains.
89. Haemophilia disease is linked with:
(A) Sex chromosome
(B) Antosomes
(C) Bacteria
(D) Virus
Answer:
(A) Sex chromosome
Explanation:
Haemophilia is a genetic bleeding disorder inherited through an X-linked recessive trait, meaning the mutated gene responsible is located directly on the X (sex) chromosome.
90. Which one of these is haploid?
(A) Embryo
(B) Gametes
(C) Foctus
(D) Zygote
Answer:
(B) Gametes
Explanation:
Gametes (sperm and egg cells) are the only cells in the human reproductive cycle that are haploid, meaning they contain a single set of unpaired chromosomes (). The zygote and embryo are diploid ().
