71.

In gymnosperms, the pollen chamber represents

• a cell in the pollen grain in which the sperms are formed.

• a cavity in the ovule in which pollen grains are stored after pollination

• an opening in the megagametophyte through which the pollen tube approaches the egg

• an opening in the megagametophyte through which the pollen tube approaches the egg

During transcription, RNA polymerase holoenzyme binds to a gene promoter and assumes a saddle-like structure, what is it’s DNA-binding sequence?

• TTAA

• AATT

• CACC

• CACC

Industrial melanism as observed in peppered moth proves that

• The true black melanic forms arise by a recurring random mutation.

• The melanic form of the moth has no selective advantage over lighter form in industrial area

• The lighter-form moth has no selective advantage either in polluted industrial area or non-polluted area

• The lighter-form moth has no selective advantage either in polluted industrial area or non-polluted area

Differentiation of organs and tissues in a developing organism, is associated with

• developmental mutations

• differential expression of genes

• lethal mutations

• lethal mutations

Lysozyme that is present in perspiration, saliva and tears, destroys

• certain fungi

• certain types of bacteria

• all viruses

• all viruses

The Okazaki fragments in DNA chain growth

• result in transcription

• polymerize in the 3’ - to - 5’ direction and forms replication fork

• prove semi-conservative natuire of DNA replication

• prove semi-conservative natuire of DNA replication

The two polynucleotide chains in DNA are

• parallel

• discontinuous

• antiparallel

• antiparallel

Which one of the following is a viral disease of poultry?

• Salmonellosis

• Coryza

• New castle disease

• New castle disease

Inheritance of skin colour in humans is an example of

• chromosomal aberration

• point mutation

• polygenic inheritance

• polygenic inheritance

Which one of the following pairs is mismatched?

• Pila globosa - pearl

• Apis indica - honey

• kenia lacca - lac

• kenia lacca - lac