1.1-2 Concept of Biology, Branches—Physical & Applied

• Living vs. Non-living:

• Living organisms have life, while non-living things do not.

• The difference between them is often unclear, as even non-living things like chemicals are fundamental to life.

• Role of Physical Sciences:

• Physics and chemistry provide the basic principles for understanding life.

• Biology, however, is essential because life exhibits unique characteristics that go beyond just the components that make it up.

• Example:

• Water, composed of hydrogen and oxygen, has properties different from those of the individual elements. Similarly, living organisms display new properties that don’t solely resemble the characteristics of their non-living components.

• Definition of Biology:

• Biology comes from the Greek words “bios” (life) and “logos” (knowledge).

• It plays a key role in fields like agriculture and medicine. Although early practices of biology existed in ancient civilizations (e.g., Greece, Egypt, India, China), they were not considered modern science at that time.

1.2 Branches of Biology

• Traditional Division:

• Biology was once divided into two main branches:

• Botany (study of plants)

• Zoology (study of animals)

• Limitations of Traditional Classification:

• Many living organisms, like bacteria and fungi, don’t fit easily into either category.

• Biology has now expanded into many specialized branches, including those that address non-plant and non-animal life forms.

• Other Divisions:

• Physical Biology: Focuses on theoretical knowledge and scientific investigation.

• Applied Biology: Focuses on practical applications of biological concepts.

1.2.1 Physical Biology

• Focus: Theoretical concepts and scientific investigations related to life.

• Key Areas of Study:

1. Morphology:

• Study of form and structure of organisms.

• Divided into two branches:

• External Morphology: Study of the external features.

• Internal Morphology: Study of internal body structures.

2. Taxonomy:

• Classification of organisms and principles of classification.

3. Physiology:

• Study of the biochemical processes and functions of organs in organisms (e.g., respiration, excretion, photosynthesis).

4. Histology:

• Study of the microscopic structure of plant and animal tissues.

5. Embryology:

• Study of the development of embryos, including the origin of gametes, fertilization, and growth processes.

6. Cytology:

• Study of individual cells, their structure, function, and division.

7. Genetics:

• Study of genes, heredity, and how traits are passed from one generation to another.

8. Evolution:

• Study of the gradual development of life and organisms over generations.

9. Ecology:

• Study of the relationship between organisms and their environment.

10. Endocrinology:

• Study of endocrine glands and the hormones they produce.

11. Biogeography:

• Study of the geographical distribution of organisms and how they evolve in relation to different environments.

1.2.2 Applied Biology

• Focus: Practical applications of biological concepts to real-world problems.

• Key Areas of Study:

1. Palaeontology:

• Study of prehistoric life forms and fossils.

2. Biostatistics:

• Use of statistics in the study of organisms.

3. Parasitology:

• Study of parasitism, including parasitic organisms and the diseases they cause.

4. Fisheries:

• Study of fish, their harvesting, management, and conservation.

5. Entomology:

• Study of insects, their effects on the environment, and methods of controlling them.

6. Microbiology:

• Study of microorganisms such as viruses, bacteria, and fungi.

7. Agriculture:

• Study of farming, crop production, and management of agricultural resources.

8. Medical Science:

• Study of the human body, diseases, and treatments.

9. Genetic Engineering:

• Study of gene manipulation and its applications.

10. Biochemistry:

• Study of the biochemical processes in organisms and how they relate to health and disease.

11. Environmental Science:

• Study of the environment and its relationship with living organisms.

12. Marine Biology:

• Study of life in the ocean and other marine environments.

13. Forestry:

• Study of forests, their management, and conservation.

14. Biotechnology:

• Use of organisms in technological applications to benefit humans.

15. Pharmacy:

• Study of the technology and industry related to medicines.

16. Wildlife:

• Study of wild animals and their conservation.

17. Bioinformatics:

• Use of computer technology to manage and analyze biological data (e.g., cancer research).