Tag: botany

An electron transport system (ETS) or electron transport chain (ETC) is a series of coenzymes and cytochromes that take part in the passage of electrons from one carrier to another and to its ultimate acceptor. The various components of ETS are arranged in five kinds of complexes, arranged in a definite sequence in the inner mitochondrial membrane.

Cyclic Photophosphorylation is the process, in which systems (like prokaryotes), just accomplishes the ADP to ATP for immediate energy for the cells. This type of photophosphorylation usually occurs in the thylakoid membrane. So the correct option is ' Electron transport system'.

Sunlight or solar radiations reaching the earth have wavelength between 300 nm (in the ultra volt rang) to 2600 nm (in the infa-red range). Part of the spectrum used in photosynthesis has a wavelength between 400-700 nm, it is called as photo synthetically active radiation (PAR). 

• A soil bacterium Agrobacterium rhizogenes causes “hairy root” disease in some dicotyledonous plants(For example, capsicum species).
• A bacterial Ri (root inducing) plasmid integrates its transfer-DNA (T-DNA) into the plant genome (DNA). As a result, rapidly growing and intensely branched (hairy) adventitious roots are developed.
  
• Hence Hairy root disease of dicot plants is caused by Agrobacterium rhizogene.
• So, the correct answer is 'Agrobacterium rhizogene'.

Root caps are present in terrestrial plants to protect the root tip from breaking away as they grow deeper through the layers of the soil. However,the roots of hydropytes that are floating or submerged do not have to grow through the abrasive layers of soil, as the roots are floating in water or the soil is soft and water logged.