Answer:
The force that pulls the moon toward Earth is called _Gravity_.
Explanation:
Gravity is the force that holds the planets in orbit around the sun and keeps the moon to orbit around Earth. the moon pulls the oceans towards it causing ocean tides, because of the gravitational pull. gravity creates planets and stars by pulling material together from which stars and planets are made.
Answer:
(c) directional selection
Explanation:
Directional selection is a type of natural selection that occurs when members of a population of a species with a particular extreme phenotype is selected or favored against the other phenotypes when natural forces act on the population of a species. Individuals having the particular traits that are favored survive and become more common that others with traits that are less favored.
Directional selection may likely result in the species of butterflies in which darkly collared butterflies are not preyed upon, ensuring their survival, while the other butterflies with other colors will be phased out with time. Darkly colored butterfly will be selected for while the others will be selected against.
Answer:
The plant cell wall is strengthened by the molecular structure of cellulose. Cellulose is made up of ß-glucose arranged upside down, this arrangement aided hydrogen bonds between the hydrogen ions of the hydroxyl group and oxygen of the of the ring of same betta -glucose.
The aggregation of the hydrogen bonds give bundles of strong tensile strength of cellulose called the microfibrils (of 60-70 celluose molecules).They are held together in bundled called fibers.T<u>hese is the source of plant cell walls strength.
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Collagen is the main extracellur matrix (EM) in animal cells.It is a glycoprotein made up of 25%of body protein of animals.Each collagen molecule is made of helix shaped ,three polypeptide chains, wound around each other to form<u> triple helix.</u>The bonds holding helix together are hydrogen and covalent bonds.
Each triple helix is attached to adjacent collagen molecule, parallel to it. The covalent bonds formed a cross link which held the collagen molecules together forming FIBRILS. This gives flexibility to collagen, while maitaing strong tensile strength. This is what is responsible for the structural strength of cell membrane
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.The EM,is futher reinforced with carbohydrate molecules(proteoglycans) which<u> aided in water movements by osmosis following sodium movements into the matrix.</u>
Answer:
<em>Involuntary </em><em>physiologic</em><em> </em><em>processes</em>
Seldom seen in adults treatment with insulin injections
