The internal environment, elements LO3, LO4

Question 1

Elements

Answer 1

All matter is composed of one or more elements
An element is a substance in which all the particles that make it up are exactly the same

Question 2

Atoms

Answer 2

particles that make up elements are called atoms
- An atom is the smallest stable unit of matter
- Different elements contain atoms of different sizes
- Atoms combine to form via chemical reactions

Question 3

Ions

Answer 3

Atoms/molecules that have an overall electric charge are called ions
Cations – positive charge, e.g. H+, Na+, K+, Ca2+
Anions – negative charge, e.g. Cl-,HCO3

Question 4

Electrolytes

Answer 4

• Electrically charged atoms or molecules (ions) in solution (i.e. water)
  -Present in all body fluids

Question 5

Classes of electrolytes

Answer 5

Salts, acid, bases

Question 6

pH scale

Answer 6

14 = base (less hydrogen ions, basic solution)
7 = neutral (equal base/acid)
0 = acidic (lots of hydrogen ions, less basic)

–> measure number of hydrogen ions
–> 7.35-7.45 for human ideal pH level

Question 7

The internal environment of the body consists of

Answer 7

• cells suspended in
• fluid that is contained by barriers, i.e. skin
• extracellular fluid
  (ECF) (1/3 of total body
  water)
• The fluid inside cells is
  called intracellular
  fluid (ICF) (2/3 of total
  body water)

Question 8

Body fluids (ECF, ICF) are solutions consisting of:

Answer 8

• Water (solvent or liquid)
• Solutes (Electrolytes, Non-electrolytes)