OMR|Plant Hybridisation|Important Facts|Heterosis / Hybrid Vigour|Inbreeding Depression

Heterosis/Hybrid Vigour || Inbreeding Depression || Polyploidy || Origin OF Bread || Wheat Selection Methods

Assertion: Hybridisation is involved in the production of hybrid vigour or heterosis. Reason: Hybrid is obtained by crossing the selected inbreed lines.

Explain the process of heterosis. How is it different from inbreeding depression?

Cross - pollinating plants (i) produce offsprings having variation among themselves . (ii) Reduces inbreeding depression . (iii) Results in the production of pure line homozygous offsprings. (iv) Having bisexual flowers or have monoecious conditions.

Most of the polyatomic molecules except a few such as CO_(2) and CS_(2) are linear or angular with a bond angle generally somewhat greater than 90^(@) A bond angle is defined as the angle between the direction of two covalent bonds Since the atoms in molecules are in constant motion with respect to each other they are not expected to have a fixed value of bond angle Repulsion between non-bonded atoms alone does not provide an adequate explanation Hybridisation of bonding orbitals an adequate explanation Hybridisation of bonding orbitals also plays a very important role in detrmining the value of bond angle It has been observed that in hybridisation as the s-character of hybrid orbital increases the bond angle increases Which of the following hybridisation may have more than one type of bond angle ? .

Most of the polyatomic molecules except a few such as CO_(2) and CS_(2) are linear or angular with a bond angle generally somewhat greater than 90^(@) A bond angle is defined as the angle between the direction of two covalent bonds Since the atoms in molecules are in constant motion with respect to each other they are not expected to have a fixed value of bond angle Repulsion between non-bonded atoms alone does not provide an adequate explanation Hybridisation of bonding orbitals an adequate explanation Hybridisation of bonding orbitals also plays a very important role in detrmining the value of bond angle It has been observed that in hybridisation as the s-character of hybrid orbital increases the bond angle increases In P_(4) molecule phosphorous atoms are tetrahedrally arranged The angle P-P-P in the molecule is .

Most of the polyatomic molecules except a few such as CO_(2) and CS_(2) are linear or angular with a bond angle generally somewhat greater than 90^(@) A bond angle is defined as the angle between the direction of two covalent bonds Since the atoms in molecules are in constant motion with respect to each other they are not expected to have a fixed value of bond angle Repulsion between non-bonded atoms alone does not provide an adequate explanation Hybridisation of bonding orbitals an adequate explanation Hybridisation of bonding orbitals also plays a very important role in detrmining the value of bond angle It has been observed that in hybridisation as the s-character of hybrid orbital increases the bond angle increases Which of the following have highest bond angle ? .

Differentiate between geitonogamy and xenoghmy in plants. Which one between the two will lead to inbreeding depression and why

Emasculation and bagging are the two important steps carried during artificial hybridisation to obtain superior varieties of desired plants. Explain giving reasons, in which types of flowers and at what stages are the two processes carried out.