The variation may already exist within the population, but often the variation comes from a mutation, or a random change in an organism's genes.
If one has an esophageal cancer it is important to have a good nutrition. Treatment can make it hard thus a soft diet and high protein food is recommended.A tube feeding would be ideal if anything can't be eaten through mouth. A tube called J tube can be put in one's small intestine or G tube if put in a stomach. Parenteral nutrition can also be done if there is an intravenous drip.
Double fertilization occurs in Angiosperms
Answer:
phospholipids, sterols, and triglycerides
Explanation:
Phospholipids make up the outermost layer of cells in the bodies of both animals and humans. They create a protective layer around the cells to help maintain them.
Sterols are a subset of steroids, a type of hormone.
Triglycerides are the fats and oils that you are familiar with in foods. This type of lipid can be saturated or unsaturated, which is part of what makes them solid or liquid, respectively, at room temperature.