Teh second statement, they can harm you but some strains are beneficial
Throughout the young larval stages a small gland behind the brain, called the corpus allatum, secretes juvenile hormone (also known as neotenin).
Mitochondria is described as the power house of the cell, because it is the cell organelle that process the production of ATP, which is the energy source of the cell. Kreb's cycle occurs in the mitochondria, it is the process by which energy is generated inside the cell, leading to the production of ATP and carbon dioxide and water are given up as waste products.
Steroids
are complex structure four connected rings of carbon atoms. They are cholesterol which is in all body cells and used to synthesize other steroids:sex hormones, such as estrogen, and testosterone and several hormones from the adrenal glands.
Waxes
are comprised of an ester of a long-chain alcohol and a fatty acid. Many plants have leaves and fruits with wax coatings to help prevent water loss.
Phospholipids
consist of Glycerol portion and fatty acid chains. Only two fatty acids chains; in place of the third is portion that include a phosphate group. THe phosphate portion is soluble in water [hydrophobic] forms the ''head'' of the molecule, while the fatty acids portion is insoluble in water [hydrophobic] and forms a ''tail''.
Fats
to store energy for cellular activities. Carbohydrates fat molecules are composed of carbon, hydrogen and oxygen atoms.
The third and last option is correct.
Species in the past (referring to dinosaurs) were more massive.
levels where higher in the past, which meant that plants prospered during that time since they had a easy access to food. That contributes to the fact that herbivores could grow bigger because there was more food. Which in turn, increases the size of early carnivores which eat bigger herbivores.
Hope it helped,
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