Answer: The human digestive system consists of the gastrointestinal tract plus the accessory organs of digestion (the tongue, salivary glands, pancreas, liver, and gallbladder). Digestion involves the breakdown of food into smaller and smaller components, until they can be absorbed and assimilated into the body.
Answer:
B. An egg cell and a sperm cell unite.
Explanation:
NADPH is the reduced form of NADP+. This simply means that NADPH has an extra hydrogen ion.
NADPH is formed when upon the reduction of NADP+ . NADP stands for nicotine amide dinucleotide phosphate. It is a coenzyme that is involved in a wide range of anabolic reactions.
During the synthesis of carbohydrates in plants, NADPH acts as a reducing agent, likewise in the synthesis of nucleic acids and lipids.
As a reduced compound, NADPH becomes a molecule with high energy thus being especially useful in driving the Calvin cycle.
Index fossils (also known as guide
fossils, indicator fossils or zone
fossils) are fossils used to define
and identify geologic periods (or
faunal stages).