Annelids have neither an external or an internal shell. Examples of annelids are
earthworms and leeches.
Answer:
The human body needs a list of macromolecules and micromolecules for performing day to day functions.
The essential macronutrients that the body requires are:
Carbohydrates: Carbohydrates are required by the cells in the body to carry out normal day to day functions. Energy is provided in the form of calories by the carbohydrates.
Proteins: Proteins are essential nutrients which are required for growth as well as better functioning of the immune cells of the body.
Fats and oils: These are needed for providing insulation to the body and to store energy.
Fibres: These are a mixture of carbohydrates.
Water: Almost every activity of the body requires water.
The essential micronutrients that the body requires are:
Vitamins: Vitamins are a group of substances which are needed by the body to function normally.
Minerals: Mineral are needed to ensure that tissues are working correctly.
In a study, competition among plants
are normal. Hence, all plants required a few basic elements like the light,
water, nitrogen, or phosphorus, depending upon the species and the location. Evidence
that can conclude that competition do really happen in plants is that some plants
release toxins into the soil, in their dropped leaves which wipe out the competition
for soil nutrients (such as weeds). And when it come an area with many trees in
close proximity such as a forest, height is also indicative of competition for
light.
I think the veins absorb the photons because they're located at the top part of a leaf while the stomata that serves as the leaf's lungs are found at the under side.