Subject

Biology

Class

NEET Class 12

Test Series

Take Zigya Full and Sectional Test Series. Time it out for real assessment and get your results instantly.

Test Yourself

Practice and master your preparation for a specific topic or chapter. Check you scores at the end of the test.

 Multiple Choice QuestionsMultiple Choice Questions

71.

Double fertilization occurs in

  • Riccia

  • Pteridium

  • Cycas

  • Capsella


D.

Capsella

Double fertilization is the characteristic feature of angiosperms, e.g, Capsella. It includes fusion of one male gamete with egg and second male gamete with a secondary nucleus (this forms endosperm).


72.

A polygenic inheritance in human beings is

  • Skin colour

  • Sickle cell anaemia

  • Colour blindness

  • Phenylketonuria


A.

Skin colour

Genes that when acting individually have a small effect but that collectively produce a significant phenotypic expression are called polygenes, e.gr inheritance of kernel colour in wheat and skin colour in human.


73.

Powdery mildew of wheat is caused by a species of

  • Puccinia

  • Erysphe

  • Ustilago

  • Albugo


B.

Erysphe

Powdery mildew of wheat-Erysiphe graminis. Loose smut of wheat-Ustilago tritici. Black rust of wheat-Puccinia graminis tritici.


74.

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

  • The microsporangium in which pollen grains develop


B.

A cavity in the ovule in which pollen grains are stored after pollination

In gymnosperms, the pollen chamber is a cavity in the ovule in which pollen grains are stored after pollination.


75.

The Montreal Protocol refers to

  • Persistent organic pollutants

  • Global warming and climate change

  • Substances that deplete the ozone layer

  • Biosafety of genetically modified organisms


C.

Substances that deplete the ozone layer

World's major producers and consumers of pollutants met at Montreal (Canada) on September 16, 1987 to solve the problem of ozone thining in stratosphere. 24 countries signed the protocol that came into force on january 1, 1989. This protocol refers to the substances such as CFCs (chlorofluorocarbons), methane that deplete the ozone layer.


76.

Ten percent law of energy transfer in a food chain is given by

  • Schimper

  • Elton

  • Haeckel

  • Lindemann


D.

Lindemann

According to Lindeman's law of trophic efficiency, the efficiency of energy transfer from one trophic level to next is about 10%.


77.

The Okazaki fragments in DNA chain growth

  • Results in transcription

  • Polymerise in the 3' to 5' direction and forms replication fork

  • Prove semi-conservative nature of DNA replication

  • Polymerise in the 5' to 3' direction and explain 3' to 5 DNA replication


A.

Results in transcription

The Okazaki fragments in DNA chain growth polymerise in the 5' to 3' direction. The replicated DNA result in transcription.


78.

Biological Oxygen Demand (BOD) is a measure of

  • Industrial wastes poured into water bodies

  • The extent to which water is polluted with an organic compound

  • Amount of carbon monoxide inseparably combined with haemoglobin

  • Amount of oxygen needed by green plants during the night 


B.

The extent to which water is polluted with an organic compound

Biological Oxygen Demand (BOD) is a meaure of polluting organic matter present in a sample of water. BOD is higher in polluted sewage water and is connected with both microbes and organic matters. When larger amount of sewage is dumped in to water, the BOD will increase.


79.

Nucleic acid segment tagged with a radiactive molecule is called

  • Clone

  • Probe

  • Plasmid

  • Vector


B.

Probe

The probe is 15-30 bases long radioactive labelled oligonucleotides (RNA or DNA) used to detect complementary nucleotide sequence, used for disease diagnosis, etc.


80.

One gene-one enzyme relationship was established for the first time in

  • Neurospora crassa

  • Salmonella typhimurium

  • Escherichia coli

  • Diplococcus pneumoniae


A.

Neurospora crassa

One gene-one enzyme relationship was initially proposed by Beadle and Tatum and based on the experiments conducted on Neurospora crassa. They were awarded by Nobel Prize in 1958 for this achievement.