2.1.2a Biological Elements Flashcards
Most common elements in the body (or all living organisms)
Carbon (C)
Hydrogen (H)
Oxygen (O)
Nitrogen (N)
Phosphorus (P) & Sulfur (S) also have important roles in cell biochemistry
What are carbohydrates made up of
Simple sugars like glucose
What are proteins made up of
amino acids
What are lipids made up of
3 fatty acids, 1 glycerol molecule
What is an atom
The smallest part of an element that can exist
What is a molecule
2 or more atoms that are physically bonded together
What is a compound
2 or more atoms chemically bonded together
What is an element
A substance whose atoms all have the same atomic number or number of protons
Role of phosphorus in the body
- makes up ATP molecules
- found in the DNA
Role of sulfur in the body
found abundantly in certain amino acids
Atomic number & mass number
ATOMIC (proton) NUMBER = bottom number
MASS NUMBER = top number
Bonding in atoms
Atoms connect to each other by bonding. When two or more atoms bond covalently, they create a molecule
The number of bonds formed for each atom depends on the number of electrons in the outer shell
What is a covalent bond
A covalent bond is the sharing of two or more electrons between two atoms.
See how to represent bonding between atoms in different ways
electron config, displayed formula, ball & stick model
Learn bonds between common molecules
on showbie, slide 9
What elements do Carbohydrates contain
Carbon, Hydrogen and Oxygen
What elements do Lipids contain
Carbon, Hydrogen and Oxygen
What elements do Proteins contain
Carbon, Hydrogen, Oxygen, Nitrogen, Sulfur
What elements do Nucleic Acids contain
Carbon, Hydrogen, Oxygen, Nitrogen, Phosphorus
What is an ion
An atom or molecule in which the total number of electrons is not equal to the total number of protons
What are cations
Ions with a net positive charge, meaning they have lost one or more electrons
eg. calcium 2+
What are Anions
Ions with a net negative charge, meaning they have gained one or more electrons
eg. chlorine into chloride
What is an ionic bond & how is it formed
One atom in a pair donates an electron & the other receives it. This forms positive & negative ions that are held together by the attraction of the opposite charges
See table on slide 15 for important ions
What are polymers
Biological molecules are often polymers.
Polymers are long chains made up by linking the individual molecules (monomers)
eg. amino acids are the monomers that form proteins
What are organic substances
Organic substances contain carbon bonded to hydrogen
What are inorganic substances
Inorganic substances lack C-H bonds
Be able to sort ions into organic or inorganic
