DNA from Salmonella species, when digested with the restriction enzyme Xba I, gives around 15 fragments ranging from 25 kb to 680 kb This pattern of fragments, or ‘fingerprint’, is unique to that strain. If the same fingerprint is found from bacteria from other infected people, then it can be assumed that they were all infected from a common source. Thus, by comparing their eating habits, food sources, etc. the source of the infection can be traced to a restaurant, food item. The fingerprints are created and analysed by

#Question id: 10810

#Unit 6. System Physiology – Plant

A mechanism for preventing sap loss entails closing sieve plate pores with callose, which is

#Question id: 10811

#Unit 6. System Physiology – Plant

In mature cells, P-protein occurs in several different forms depending on the species. Such as;

#Question id: 10812

#Unit 6. System Physiology – Plant

P-protein occur only in certain legumes and are encoded by members of the gene family known as;

#Question id: 10813

#Unit 6. System Physiology – Plant

A living cytoplasmic connection penetrate the walls between sieve tube elements and their companion cells; which are often complex and branched on the companion cell side, known as

#Question id: 10899

#Unit 6. System Physiology – Plant

Companion cells transport of photosynthetic products from producing cells in mature leaves to the sieve elements in the minor veins of the leaf. There are at least three different types of companion cells in the minor veins of mature, exporting leaves, All three cell types have dense cytoplasm and abundant mitochondria;

#Question id: 10900

#Unit 6. System Physiology – Plant

companion cells in minor veins of mature leaves. All three cell types have dense cytoplasm and abundant mitochondria, there are three types companion cells  present in column A while its characteristics given in column B;

             COLUMN A                                                               COLUMN B

A) Ordinary companion cells             i) appear well suited for taking up solutes via cytoplasmic connections numerous plasmodesmata connecting them to bundle sheath cells. Its having numerous small vacuoles, as well as poorly developed thylakoids.

B) Transfer cells                                 ii) have chloroplasts with well-developed thylakoids     and a cell wall with a smooth inner surface. The number of plasmodesmata connecting ordinary companion cells to surrounding cells.

 C) Intermediary cells                          iii) the development of fingerlike wall in growths, particularly on the cell Walls. These wall ingrowths greatly increase the surface area of the transfer cell’s  plasma membrane, few plasmodesmata connect this type of companion cell to any of the surrounding cells except its own sieve element.

Which of the following correct combination;