Explanation:
The valence electrons determine the group the elements belong in the periodic table. For example, the element sodium, Na, has a valence electron of one and so it belongs to Group 1 in the periodic table. Another example is Aluminium, Al, which has a valence electron of three and therefore it belongs to Group 3 in the periodic table.
I believe its the centromere yes its the centromere :)
Answer:organs
Explanation:the body of multicellular organisms are organised into levels of organization.these levels increases in complexity.
The macromolecules makes up the organelles . organelles in turn makes up the cell.A group of similar cells at a certain location makes up an organ.for example the heart consists of a number of cells.
A group of organs which work together to achieve a specific function in the body , makes up the organs system.
For example the circulatory system of a while is made up of different connected organs - heart, blood vessels,to perform the function of transporting blood around it's body.this makes it an organ system.
Tight hydrogen bonding
The atoms in a compound are held together by a chemical bond. The chemical bonds can be either covalent bonds or ionic bonds. Both the bonds are considered very strong bonds. These bonds are mainly formed by sharing of electrons or in the case when one of the elements making the compound donates electron to the other element. The nucleus of each atom attracts to form a strong bond. This property of attraction between the nucleus of the atoms actually helps in forming the chemical bonds.<span>
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