<u>Answer:</u>
Option (C)
There is no change in mass during a chemical reaction;
<u>Explanation:</u>
The law of mass conservation can better explain this phenomenon. According to the rule, "Energy can not be either produced, nor can it be lost."
In simpler terms, the total masses of all substance involved in a chemical reaction are same. Furthermore, the total atoms on either sides, i.e., reactant side and product side are the b.
An animal can respond in negative ways such as: biting, scratching, urinating, whining, restlessness, snippy, or getting sick.
Ecosystems equilibrium is when populations of organisms in the ecosystem are balanced.
Answer:
Option A, a compound that contains carbon atoms bound to other elements
Explanation:
An organic compound is one which has at least one carbon atom that is bonded to several other atoms (may be metallic or non metallic) by a single or double bond is termed as organic compound . The most common atoms with which carbon forms bond are hydrogen, nitrogen,and oxygen.
Some common examples are -
Methane - 
Methanol - 
Hence, option A is correct
Answer:
e. cutin
Explanation:
Plant exhibit many variations to withstand the temperature variations, desiccation and increased UV exposure which are some of the factors associated with land habitat. Cutin is a waxy substance that is found in the outer walls of the epidermal cells of plants. Cuticle in plants serves to make the outer most covering of aerial parts of the leaves and non-woody stem of herbaceous plants. The cuticle is made of cutin.
Cutin serves to protect the plant’s aerial surfaces from excess water loss. It also filters the excess UV light and thereby protects the underlying plant parts. The thickness of the cuticle varies in different plants depending upon the environmental conditions. The leaves of plants adapted to hot, dry climates have thick cuticles. The thickness of the cutin layer also varies in different parts of a plant. For example, the upper epidermis of leaf generally has a thicker cuticle than the shaded and relatively cooler lower epidermis.