Why does testosterone, a lipid-soluble signaling molecule that crosses the membranes of all cells, affect only target cells?

#Question id: 10507

#6. System Physiology – Plant

Rhizobacteria function as

 a) Nitrogen fixation

 b) depositing pathogens directly into the vascular system,

 c) producing antibiotics and antifungal agents for inhibiting soil pathogens

 d) herbivore sensors by sending electrical or chemical signals to surrounding cells

 Which one of the following combination is correct?

#Question id: 10508

#6. System Physiology – Plant

Glandular trichomes store species-specific secondary metabolites in a pocket formed between the cell wall and the cuticle. These secondary metabolites are-

#Question id: 10509

#6. System Physiology – Plant

A different type of mechanical obstacle to herbivory is provided by mineral crystals that are present in many plant species, such as silica crystals known as

#Question id: 10510

#6. System Physiology – Plant

Constitutive chemical defenses are effective against many different herbivores, including insects and mammals. Hemlock (Cicuta sp.) produces which toxins that a polyacetylene prolongs the repolarization of neuronal action potentials.

#Question id: 10511

#6. System Physiology – Plant

Which type of pumps inhibits digitoxin in the membranes of heart cells, leading to increased myocardial contraction?

#Question id: 10512

#6. System Physiology – Plant

Members of the Poaceae family, which includes all of the cereal crops, use benzoxazinoids alkaloids are derived from,