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TLS Online TPP Program

#Question id: 2211

Which of these statements about facilitated diffusion across a membrane is true?

#Unit 2. Cellular Organization

  1. A specific membrane protein lowers the activation energy for movement of the solute through the membrane.

  2. It can increase the size of a transmembrane concentration gradient of the diffusing solute.

  3. It is impeded by the solubility of the transported solute in the nonpolar interior of the lipid bilayer.

  4. It is responsible for the transport of gases such as O2, N2, and CH4 across biological membranes.

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TLS Online TPP Program

#Question id: 11794

#Unit 1. Molecules and their Interaction Relevant to Biology

Glypicans are derivatives of
TLS Online TPP Program

#Question id: 11795

#Unit 1. Molecules and their Interaction Relevant to Biology

_________ residue in a tetrasaccharide linker connects a glycosaminoglycan such as chondroitin 4-sulfate to _______ residue in the core protein. The residue at the reducing end of the linker is joined by its anomeric carbon to the hydroxyl of this residue.
TLS Online TPP Program

#Question id: 11796

#Unit 7. System Physiology – Animal

Which of the following hormones is largely unbound to plasma proteins?
TLS Online TPP Program

#Question id: 11797

#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
TLS Online TPP Program

#Question id: 11798

#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;
TLS Online TPP Program

#Question id: 11799

#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;