19. B - mitochondria
20. D - vegetative structure
21. C - inducing a mutation
22. A - phosphates
23. C - fungi
24. A - provides support
25. C - sponges
26. B - opposite charges
27. D - asexual reproduction
28. not sure about this one sorry
29. D - all of the above
30. A - prevents ions and large molecules from passing through the membrane
Species is the basic unit of classification denoted by a unique two-part scientific name.
<h3>What is meant by species? </h3>
Species is a name given to a group of organisms which have similar individuals. They are capable of reproducing among themselves and thus exchanging genes among themselves.
Species is the lowest of taxa and is thus the most basic unit of classification. Genus is the next taxonomic rank of the next taxa on the hierarchy of classification.
It is estimated that on earth, there are 8.7 million species living currently. This concept of species is from the times of Aristotle.
Therefore, species is the basic unit of classification denoted by a unique two-part scientific name.
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<span>a. Fish have a single central heart; earthworms have several hearts.
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Multi cellular organisms are made up of billions of cells each specialized to a unique role and these cells are organized into structural and functional units such as tissues and organs.
For each cell and organ to function optimally, it requires oxygen and nutrients and needs carbon dioxide and metabolic waste taken away in a continuous, never ending process.
<span>A mechanism is needed to accomplish the important function of transporting the relevant materials to and from the cell. The circulatory system fits this bill splendidly. It is a specialized organ system which allows blood and lymph to flow through the entire body carrying nutrients such as glucose, amino acids and electrolytes as well as oxygen to each cell, at the same time carting away carbon dioxide and all sorts of metabolic waste over to excretory organs to be expelled from the body.
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The term would be leukocytosis and this usually indicates that there is presence of an infection.
The angle bisector theorem is commonly used when the angle bisectors and side lengths are known. It can be used in a calculation or in a proof. An immediate consequence of the theorem is that the angle bisector of the vertex angle of an isosceles triangle will also bisect the opposite side.