Book Store

Currently only available for.
CBSE Gujarat Board Haryana Board

Previous Year Papers

Download the PDF Question Papers Free for off line practice and view the Solutions online.
Currently only available for.
Class 10 Class 12

Which one of the following is incorrect about the characteristics of protobionts  (coacervates and microspheres) as envisaged in the abiogenic origin of life?

• They were able to reproduce

• They could separate combinations of molecules from the surroundings

• They were partially isolated from the surroundings

• They could maintain an internal environment

D.

They could maintain an internal environment

Homoeostasis is keeping the internal environment of the body constant. It is necessary for normal life processes. Microspheres are molecular aggregates of proteinoids. Oparin and Sydney Fox held that large organic molecules synthesized abiotically on primitive earth formed large colloidal aggregates due to the intermolecular attraction. These colloidal particles were called coacervates. Oparin called giant nucleoprotein poid molecules as protobionts. These reproduce either by budding a binary fission but do not exhibit homoeostasis.

Homoeostasis is keeping the internal environment of the body constant. It is necessary for normal life processes. Microspheres are molecular aggregates of proteinoids. Oparin and Sydney Fox held that large organic molecules synthesized abiotically on primitive earth formed large colloidal aggregates due to the intermolecular attraction. These colloidal particles were called coacervates. Oparin called giant nucleoprotein poid molecules as protobionts. These reproduce either by budding a binary fission but do not exhibit homoeostasis.

662 Views

Arrange the following substances in a proper sequence with regard to the formation of chemical constituents at the time of origin of life :

Sugar, methane, nucleic acid and amino acid.

Methane—sugar—amino acid—nucleic acid.
752 Views

When did life appear on earth ?

500 million years ago.
996 Views

Give another name for origin of life from non living matter.

Abiogenesis
771 Views

What is the phenomenon called when the original drifted population becomes founders?

Founder Effect.
733 Views

What conditions were created by Miller in his experiment?

Miller  created electric discharge in a closed flask that contained CH4, NH3, H2 and water vapour at high temperature like 800$°\mathrm{C}$
708 Views