<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 answer to that is James Watson and Francis Crick although if you search up on a search engine who found it Francis Crick will only show up.
The cell membrane<span> is selectively permeable to ions and organic molecules and controls the movement of substances in and out of </span>cells<span>. The basic </span>function of the cell membrane<span> is to protect the </span>cell<span> from its surroundings. It consists of the phospholipid bilayer with embedded proteins.</span>
Answer:
No children will have blue eyes all of them carry brown eyes only.
Explanation:
The cross between a male with bb genotype and female with BB genotype will be as follows :
The gametes will be formed
male: b and b
female: B and B
By Punnett square:
B B
b Bb Bb
b Bb Bb
As all the offspring will have a heterozygous condition with dominant B (Brown) and recessive b( blue) so there are no offspring will be with the phenotype of the blue eyes.