Biology (Detailed, University
Level)
1.1 What is Biology?
Biology is the scientific study of life and
living organisms, encompassing their
structure, function, growth, origin,
evolution, and distribution. It bridges
molecular processes (like DNA replication) to
global ecological systems.
●Definition: "Biology is the natural science
that studies life and living organisms,
including their physical structure, chemical
processes, molecular interactions,
physiological mechanisms, development,
and evolution." – Campbell Biology
(MIT/Harvard Reference Standard)
, ●Focus Areas:
1. Structure – anatomy of cells, tissues,
organs, and organisms.
2. Function – physiological and
biochemical mechanisms.
3. Growth & Development – from single
cell to mature organism.
4. Evolution – genetic variation and
adaptation over time.
5. Interaction – ecological interactions
and symbiotic relationships.
Branches of Biology:
Branch Focus Area
,Zoology Animals
Botany Plants
Microbiol Microbes, Bacteria,
ogy Viruses
Genetics Heredity, DNA, Genes
Ecology Organism-Environme
nt Interaction
Molecula DNA, RNA, Proteins,
r Biology Biochemical
Processes
Biotechn Genetic Engineering,
ology Synthetic Biology
, 1.2 Characteristics of Living Organisms
All living organisms share fundamental
characteristics:
1. Cellular Organization:
○All organisms are composed of cells,
the basic unit of life.
○Types: Prokaryotic (bacteria, archaea)
vs Eukaryotic (plants, animals, fungi).
2. Metabolism:
○Organisms convert energy from
nutrients into usable forms.
○Anabolism: building complex molecules
(e.g., protein synthesis).