A is an example of a signal molecule that can bind to an intracellular receptor and thereby cause a gene to be turned on or off. a protein b glyceride c nucleic acid d steroid e carbohydrate

D. steroid

Explanation:

Intracellular receptors are a type of receptors located inside the cell, specifically in the cytoplasm or nucleus. When intracellular receptors are activated by ligands called SIGNALLING MOLECULES, they change shape and regulate genetic expression in the nucleus i.e. they induce turning on and off in a gene.

However, signalling molecules that activate intracellular receptors are usually hydrophobic hormones because they need to easily diffuse through the cell membrane and bind to the receptors located internally. Example of these hydrophobic signal molecules are STEROIDS.

ans.

gregor john mendel is known for study of inheritance in pea plants. he used garden pea plant for his study, having alternative traits for various characters. he performed cross-breeding in pea plants to check how characters are transmitted between parents to offspring, such as cross between pure tall and pure dwarf plant. mendel studied the inheritance patterns in pea plants for various generations.

thus, the correct answer includes options and f).

1: most common garden plants prefer loam — soils with a balance of different-sized mineral particles (approximately 40% sand, 40% silt, and 20% clay) with ample organic matter and pore space. however, some plants grow better in sandy soils, while others are well-adapted to clay soils.

2: available water capacity is the maximum amount of plant available water a soil can provide. it is an indicator of a soil's ability to retain water and make it sufficiently available for plant use. available water capacity is the water held in soil between its field capacity and permanent wilting point.

3: it is the same for all living things (plants and animals). it also includes very tiny organisms that our eyes cannot see. they are known as microorganisms, and include viruses, bacteria and fungi.