Week 1 Bioscience

Question 1

The Internal Environment

Answer 1

The internal environment consists of cells suspended in fluid. Fluid inside the cells in called intracellular fluid (ICF). Fluid outside the cells is called the extracellular fluid (ECF).

Question 2

Body fluid compartments

Answer 2

Total body water Volume 40L= 60% body weight
ECF Volume 15L= 20% body weight
ICF Volume 25L= 40% body weight
IF Volume 12L= 80% ECF

Question 3

Chemical reactions

Answer 3

3 types of chemical reactions
◦ Synthesis / anabolic
◦ Decomposition / catabolic
◦ Exchange / displacement

Question 4

Ions and Electrolytes

Answer 4

Atoms/molecules that have an overall electric charge are called IONS

Substances that we release ions into water are called electrolytes

Question 5

Organic molecules

Answer 5

• more complex
• contain c & h
• typically insoluble in water
• 4 macromolecules

Question 6

Inorganic molecules

Answer 6

• simpler molecules
• do not contain both c & h
• typically soluble
• ionic compounds

Question 7

pH

Answer 7

-The pH scale is a measure of how acidic or basic a solution is
-Solutions with a lower concentration of hydrogen ions are more basic/alkaline
-Solutions with a higher concentration of hydrogen ions are more acidic

Question 8

Carbohydrates

Answer 8

Building blocks: simple sugars (monosaccharides)
provides energy for cellular function

Question 9

Lipids

Answer 9

Building blocks: fatty acids and glycerol
Functions: (3 types of lipids)
Triglycerides
◦ Long term energy storage
◦ Thermal insulation
◦ Protection from mechanical trauma

Question 10

Nucleic Acids

Answer 10

Building blocks: nucleotides

Functions: DNA (deoxyribonucleic acid)
◦ hereditary information
◦ encodes genes
Gene: the span of DNA with instructions for one protein

Question 11

Steroids

Answer 11

◦ Cholesterol – cell membranes
◦ Vitamin D – bone growth
◦ Steroid hormones – various body functions
◦ Bile salts – fat digestion

Question 12

Proteins

Answer 12

Building blocks: Amino acids

Functions: structural material of the body
The structure of a protein determines its function
◦ 2 structural classifications:
◦ Fibrous proteins
◦ Globular proteins

Question 13

nervous system

Answer 13

• nervous impulses
  -electrical
• rapid
• short lived
• limited target range

Question 14

endocrine system

Answer 14

• hormones
• chemical
• slow acting
• long lived
• wide target range