The critical difference is that,

In short-day (i.e., winter flowering) plant species, P_FR inhibits flowering.

In long-day (i.e., summer-flowering) plant species, P_FR induces flowering.

TLS Online TPP Program

#Id: 7741

#Unit 1. Molecules and their Interaction Relevant to Biology

Atomic radii: The atomic radii of an atom depends on its position in the periodic table.

We can never determine the atomic radius of an atom because there is never a zero probability of finding an electron, and thus never a distinct boundary to the atom.

All that we can measure is the distance between two nuclei (internuclear distance).

TLS Online TPP Program

#Id: 7742

#Unit 1. Molecules and their Interaction Relevant to Biology

Atomic radii: The atomic radii of an atom depends on its position in the periodic table.

We can never determine the atomic radius of an atom because there is never a zero probability of finding an electron, and thus never a distinct boundary to the atom.

All that we can measure is the distance between two nuclei (internuclear distance).

TLS Online TPP Program

#Id: 7743

#Unit 1. Molecules and their Interaction Relevant to Biology

A covalent radius is one-half the distance between the nuclei of two identical atoms.

TLS Online TPP Program

#Id: 7744

#Unit 1. Molecules and their Interaction Relevant to Biology

An ionic radius is one-half the distance between the nuclei of two ions in an ionic bond.

TLS Online TPP Program

#Id: 7745

#Unit 1. Molecules and their Interaction Relevant to Biology

The noble gases are left out of the trends in atomic radii because there is great debate over the experimental values of their atomic radii.

The SI units for measuring atomic radii are the nanometer (nm) and the picometer (pm). 1 nm = 1 X 109 m; 1 pm = 1 X 10-12 m.

TLS Online TPP Program

#Id: 7746

#Unit 1. Molecules and their Interaction Relevant to Biology

The noble gases are left out of the trends in atomic radii because there is great debate over the experimental values of their atomic radii.

The SI units for measuring atomic radii are the nanometer (nm) and the picometer (pm). 1 nm = 1 X 109 m; 1 pm = 1 X 10-12 m.