Ch 01: Introduction to Biology

Aristotle

Father of Biology

Lamarck & Treviranus

Coined the term 'Biology'

Greek: Bios + Logos

Life + Study

🔬 What is Biology?

Term 'Biology' coined by Lamarck and Treviranus
Father of Biology → Aristotle
Study of living organisms called Biology
Examples: Fungi, Algae, Bacteria, Plants, Animals, Humans, etc.

⚠ Exam Trap

Lamarck and Treviranus coined the term “Biology,” whereas Aristotle is known as the Father of Biology. These are two distinct facts and should not be confused.

📌 Living Organisms — Examples

Microbes:Fungi, Algae, Bacteria, Protozoa Plants:Trees, Creepers, Shrubs, Bryophytes, Ferns Animals:Earthworm, Fish, Birds, Mammals, Snakes

🌿 Botany

Father: Theophrastus
Study of Plants
Algae, Bryophytes, Ferns, Trees, Creepers, Shrubs

🐾 Zoology

Father: Aristotle
Study of Animals
Earthworm, Fish, Snakes, Birds, Mammals

🦠 Microbiology

Father: Antonie van Leeuwenhoek
Study of Microbes
Blue-green algae, Bacteria, Protozoa

📚 Main Sub-Branches of Biology

Sub-branch (Father)	Study of
Endocrinology (Thomas Addison)	Endocrine System & Hormones
Immunology (Edward Jenner)	Immune System & Immunity
Genetics (Gregor Johann Mendel)	Heredity & Variations in organisms
Cytology (Robert Hooke)	Cell Structure, Function & Behaviour
Eugenics (Francis Galton)	Factors influencing human generations
Taxonomy (Carolus Linnaeus)	Identifying, Naming & Classifying organisms
Paleontology (George Cuvier)	Fossils
Embryology (Indian founder: Panchanan Maheshwari)	Gametes, Fertilisation & Embryo development
Agronomy (Pietro de crescenzi)	Crop Production & Soil Management
Agrostology (Johann Scheuchzer)	Grasses
Anthology	Flowers
Serpentology (Patrick Russell)	Snakes
Protozoology (Antonie van Leeuwenhoek)	Protozoa

⚡ Quick Recall

Father Trick: Mendel → Genetics | Hooke → Cytology | Jenner → Immunology | Galton → Eugenics | Cuvier → Paleontology

🏷️ Taxonomy — Key Facts

Term 'Taxonomy' coined by → Augustin Pyramus de Candolle
Father of Taxonomy → Carolus Linnaeus
Taxonomy = Identifying, Naming & Classifying Living Organisms

⚠ Exam Trap

De Candolle coined the term “Taxonomy,” whereas Linnaeus is known as the Father of Taxonomy. These are distinct facts.

📖 Binomial Nomenclature

Introduced by Carolus Linnaeus — book: Systema Naturae
Unique name = Genus + Species
Written in Italics; Genus starts with capital, species in small letters

Example:Homo sapiens → Genus: Homo | Species: sapiens

🔢 Taxonomic Hierarchy (Descending Order)

1Kingdom → 2Phylum (Animals) / Division (Plants) → 3Class → 4Order → 5Family → 6Genus → 7Species

⚡ Quick Recall — Mnemonic

King Philip Came Over For Good Soup

🧬 Taxonomic Classification — Key Organisms

Common Name	Biological Name	Family	Order	Class	Phylum/Division
Human	Homo sapiens	Hominidae	Primates	Mammalia	Chordata
House Fly	Musca domestica	Muscidae	Diptera	Insecta	Arthropoda
Mango	Mangifera indica	Anacardiaceae	Sapindales	Dicotyledonae	Angiospermae
Wheat	Triticum aestivum	Poaceae	Poales	Monocotyledonae	Angiospermae
Potato	Solanum tuberosum	Solanaceae	Solanales	Dicotyledonae	Angiospermae

⚠ Exam Trap

In a herbarium, plants are preserved by drying and pressing them.

🔢 Five Kingdom Classification — Overview

Proposed by Robert Whittaker in 1969
Criteria:
- Cell Structure
- Body Organisation
- Mode of Nutrition
- Reproduction & Phylogenetic relationship

📊 Five Kingdoms — Comparison Table

Feature	Monera	Protista	Fungi	Plantae	Animalia
Cell Type	Prokaryotic	Eukaryotic	Eukaryotic	Eukaryotic	Eukaryotic
Cell Wall	Peptidoglycan	Present in few	Chitin	Cellulose	Absent
Nuclear Membrane	Absent	Present	Present	Present	Present
Body Organisation	Unicellular	Unicellular	Multicellular / Thalloid	Tissue/Organ/Organ System	Tissue/Organ/Organ System
Nutrition	Auto & Hetero	Auto & Hetero	Heterotrophs (Saprophyte & Parasitic)	Autotrophs	Heterotrophs (Holozoic & Parasitic)
Reproduction	Binary fission & some sexual	Asexual & Sexual	Spores, Asexual & Sexual	Vegetative & Sexual	Sexual

⚠ Exam Trap

The fungal cell wall is made of Chitin, not cellulose. Cellulose is found in plant cell walls. This is a common MCQ trap.

⚡ Quick Recall

Only Monera is prokaryotic (no true nucleus); all other kingdoms are eukaryotic. A cell wall is absent in Animalia.

🦠 Kingdom Monera

Absence of True Nucleus
Oldest known microorganisms on Earth

1. Archaebacteria (Ancient bacteria)

Methanogens — Methane producing, e.g. Methanobacterium
Halophiles — Saline marine, e.g. Halococcus
Thermoacidophiles — Hot sulphur springs, e.g. Sulfolobus

2. Eubacteria (True bacteria)

Cyanobacteria — Nitrogen fixing, blue-green autotrophic bacteria
Mycoplasma — No cell wall, parasitic or saprophytes

⚡ Quick Recall

Nostoc & Anabaena (Cyanobacteria) → Fix atmospheric nitrogen via specialized cells called Heterocysts

🌿 Symbiotic Organisms

Symbiotic relationship → Benefits to both organisms

🍄 Lichen

Fungi (water & mineral absorption) + Algae (photosynthesis)
Pioneer organism on bare rocks
Air pollution (SO₂) indicator
Source of Litmus dye

🌱 Mycorrhiza

Fungi (mineral absorption — Phosphorus, protection) + Roots of higher plant (shelter & nutrition)
Examples: Pinus and Orchids

⚠ Exam Trap

Lichen = Fungi + Algae. It is a pioneer on bare rocks and an indicator of SO₂ pollution. Also remember that lichens are a source of litmus dye; these facts are frequently tested in MCQs.

🔬 Ultramicroscopic Acellular Structures

Virus	Viroids	Prions
Discovery of first virus → Ivanowsky (TMV)	Discovered by → T.O. Diener	Discovered by → Stanley B. Prusiner
Crystallization → Stanley (TMV)	Free, microscopic, circular particles of RNA	Infectious protein particles
Obligate parasite	Cause stunt disease in Chrysanthemum	Cause Scrapie in sheep & goats
Connecting link between living & non-living	—	Cause CJD & Kuru disease in humans
Structure: Protein coat (capsid) + Nucleic acid (DNA or RNA)	—	—

⚡ Quick Recall

TMV = Tobacco Mosaic Virus. Ivanowsky = Discovery | Stanley = Crystallization. Virus = Living + both living and non-living features. Prions = Protein only (no nucleic acid).

⚠ Exam Trap

Viroids contain only RNA and have no protein coat. Prions contain only protein and have no nucleic acid. Viruses contain both nucleic acid and a protein coat.

🐾 Animals — Biological Names

Common Name	Biological Name
Peacock	Pavo cristatus
Frog	Rana tigrina
Cat	Felis catus
Dog	Canis lupus familiaris
Cow	Bos taurus
Buffalo	Bubalus bubalis
Goat	Capra aegagrus hircus
Tiger	Panthera tigris
Lion	Panthera leo
Leopard	Panthera pardus
Bear	Ursus thibetanus
Rabbit	Oryctolagus cuniculus
Elephant	Elephas maximus indicus
Dolphin	Platanista gangetica

⚠ Exam Trap

Tiger, lion and leopard all belong to the genus Panthera, but they are different species.

🌿 Plants — Biological Names

Common Name	Biological Name
Carrot weed	Parthenium hysterophorus
Pea	Pisum sativum
Mustard	Brassica campestris
Fig	Ficus carica
Tomato	Solanum lycopersicum
Rice	Oryza sativa
Banyan	Ficus benghalensis
Sugarcane	Saccharum officinarum
Onion	Allium cepa
Asafoetida (Hing)	Ferula asafoetida
Cotton	Gossypium
Coffee	Coffea arabica
Tea	Camellia sinensis
Turmeric (Haldi)	Curcuma longa

⚡ Quick Recall

Rice = Oryza sativa | Wheat = Triticum aestivum | Potato = Solanum tuberosum | Tea = Camellia sinensis — these four names are among the most frequently tested in examinations.

📗 Chapter 01 — Introduction to Biology & the Living World