Online Module: Introductions to the foundation of biomedical science Flashcards
(61 cards)
How many of the 118 elements on the periodic table make up our bodies?
Only 20 of the 118 elements including, H, C, O, N, Na, Mg, Si, P, S, Cl, K, Ca, V, Cr, Mn, Fe, Co, Cu, Zn, As, Se, Mo and I
What is an atom ?
An atom is the smallest unit of matter that makes up an element and which takes place in a chemical reaction.
What percentage of water is found in our bodies?
60-75%
What is an element?
Elements are pure substances (which means they can only be made up of the one type of atom) and are responsible for bodily functions . They cannot be simplified and there are 118 elements.
What elements are found in proteins
Carbon, hydrogen, oxygen and nitrogen
What elements are found in fats and carbohydrates?
Carbon, hydrogen and oxygen
What elements are found in bone?
Calcium and phosphorus
What percentage does C, H, O and N make in the body
95%
What is a molecule?
Simplest unit of a pure substance retaining characteristics of the substance. When atoms of identical elements come together to form bonds H2, O2, etc
Compound
When atoms of different elements combine to form molecules they are referred to as compounds.
What is an atom made of?
- Positively charged proton
- Negatively charged Electron
- Neutrally charged neutron
Why don’t electrons, orbiting the nucleus spiral away?
Due to the electrostatic attraction between the positively charged nucleus and the negative electrons
What is the mass of a proton
1 atomic mass unit
What is a mass of a neutron
1 atomic mass unit
What is a mass of an electron?
relatively 0
What does the atomic number of an element indicate
The number of protons in the atom, and therefore, the number of electrons
What does the atomic mass (molecular mass) indicate
The proton + neutron (in amu)
Do all atoms of the same element have the same mass?
No, even though they are the same element, isotopes of an element do exist which causes the atom to vary in mass. These isotopes of the elements must all share the same number of protons but their neutrons may vary.
What is an isotope
An isotope is an atom of an element with different mass. They share the same number of protons but they differ in the number of neutrons causing them to have different mass
What is relative atomic mass
The mass of an element when taking into account
- the number of different isotopes
- the weight of the isotopes
- how abundant they are in nature
It is the average mass of the naturally occurring atoms of an element in atomic mass units
What are principal energy levels
These are the levels in which the electrons orbit around the nucleus. Each level can hole a maximum amount of electrons before a new level is introduced. As we go down the periodic table, atoms of that particular element would require an additional level.
What component of the atom is most involved in bonding and chemical reactions
The valence electrons. The noble gas (group 8) element have full outer valence orbitals and therefore do not participate in chemical reactions as easily
Octet Rule
States that atoms require 8 electrons in the outer orbital in order to be stable. They do this by gaining, losing or sharing electrons
What is an ion
An atom is a neutrally charged particle as the number of protons are equal to the number of electrons. However, when these atoms lose or gain electrons, they become charged and are called ions
