Biological elements - 3.1 (1) Flashcards
Page 40
What are cells and cellular components made from?
smaller components called molecules
What are molecules made from?
atoms
What are atoms made from?
protons, neutrons, and electrons
What are different types of atoms called?
elements
How are elements known by?
the number of protons in their atomic nuclei / nucleus
How many known elements are in the world?
over 100, but only a small % are present in the living world
What are the four key elements that all living things are made from?
carbon (C), hydrogen (H), oxygen (O), and nitrogen (N)
What are the two other elements which also have important roles in the biochemistry of cells?
phosphorus (P) and sulfur (S)
What 4 other elements have important roles in the biochemistry of cells?
sodium (Na), potassium (K), calcium (Ca), and iron (Fe)
How do atoms connect with each other?
by forming bonds
What can atoms bond with?
other atoms of the same or different element, as long as they follow the ‘bonding rules’
What is the complex called when two or more atoms are bonded together?
a molecule
When does a covalent bond occur?
when two atoms share a pair of electrons
What is unpaired and present in the outer orbitals of the atoms?
the electrons which are used to form bonds
