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ORGANIC EVOLUTION - INTRODUCTION Evolution means opening out or unfolding. It explains the formation of non living things evolution-of-man and living things. The term organic evolution means continuous change or descent with modification or the developmental stages of an organism repeats the developmental stages of ancestors. The…
The origin of life on earth and organic evolution are two fundamental aspects in modern biology. Origin of life means the origin of first living organism. Organic evolution means the formation of complex organism from simple organism over a period of time. It means the formation of life on the planet…
Zoo Geography is a branch of biological science studies about the different kinds of animals on different regions on the earth. The following list of contents clearly explains about the basic concepts of zoogeography. INTRODUCTION TO ZOOGEOGRAPHY ZOOGEOGRAPHY: PALAEARCTIC REGION ZOOGEOGRAPHY: NEARCTIC REGION ZOOGEOGRAPHY: NEOTROPICAL REGION ZOOGEOGRAPHY: AUSTRALIAN REGION ZOOGEOGRAPHY:…
CHORDATE ORIGIN OF CHORDATES GENERAL CHARACTERS OF CHORDATES BIOLOGY OF CHORDATES CLASSIFICATION OF PHYLUM CHORDATE CEPHALO CHORDATE GENERAL CHARACTERS OF CEPHALOCHORDATA CEPHALOCHORDATA: CLASSIFICATION AND SYSTEMATIC POSITION AMPHIOXUS: EXTERNAL CHARACTERS AMPHIOXUS: SKELETON AMPHIOXUS: NOTOCHORD AMPHIOXUS: ENDOSTYLE AMPHIOXUS: ATRIUM AMPHIOXUS: REPRODUCTION AMPHIOXUS REPRODUCTION: POST FERTILISATION CHANGES AMPHIOXUS: ORGANOGENY UROCHORDATA GENERAL CHARACTERS OF…
Definition of Comparative Anatomy: is a one of the branches of biology studying the similarities and differences of internal organs between different groups of organisms. The following topics are detailed discussed in simple words. COMPARATIVE ANATOMY: INTEGUMENT IN FISH AND FROG COMPARATIVE ANATOMY: INTEGUMENT IN REPTILES, BIRDS AND…
VERTEBRATES CHARACTERS OF VERTEBRATES CLASSIFICATION OF VERTEBRATA CYCLOSTOMATA GENERAL CHARACTERS OF CYCLOSTOMATA CLASSIFICATION OF CYCLOSTOMATA BRANCHIAL BASKET OF PETROMYZON DIFFERENCES BETWEEN PETROMYZON AND MYXINE AMMOCOETES LARVA PIECES GENERAL CHARACTERS OF FISHES (PIECES) CLASSIFICATON OF PISCES (FISHES) NEUROMAST SYSTEM IN FISHES OLFACTORY LOBES IN SHARKS CLASPERS IN SHARKS…
The backbone lacking animals are called invertebrates. Based on their structure they are classified into different phyla. The following list contains examples of characters of each phyla and the classification of each invertebrate phylum with examples. PROTOZOA AN INTRODUCTION TO PROTOZOA GENERAL CHARACTERS OF PROTOZOA CLASSIFICATION OF PROTOZOA…
ORIGIN AND EVOLUTION OF LIFE The following list of contents detail discussion about origin of life on the earth and evolution of life on the earth. ORIGIN OF LIFE ORGANIC EVOLUTION - LAMARCKISM NATURAL SELECTION CRITICISM OF DARWINISM DARWINISM - ARTIFICIAL SELECTION MUTATION THEORY NEO DARWINISM ORGANIC EVOLUTION EVIDENCES ORGANIC…
In 1832 "Robert Brown" discovered nucleus. It is the essential part of the cell. A definite nucleus is absent in prokaryotic cell. Instead of it a DNA molecules is present. It is called by “Prokaryotic cell". Ex: Bacteria. Definite nucleus is present. It is covered by nuclear membrane.…
In the cytoplasm of the cell complex membrane bounded system is present. It was called cytoplasmic vacuolar system by "Sacz & De robertis" in 1975. This system contains endoplasmic reticule, nuclear envelop, and Golgi. Endoplasmic Reticulum (E.R.) was first observed by "Porter, Claude, Fullam" in 1945. Occurrence: In…
In the animal and plant cells clusters of fat filled structures are present. They are called Golgi apparatus or complex. In 1898 Camillo Golgi' recognised it in the nerve cell of the owl. The Golgi complex of invertebrates is called dictyosome. Occurence: Golgi complex is seen in all eukaryotic…
Lysosome: These are first observed in liver cells. They are 1.5 to 2 milii micron in size These are single membrane bounded structures. They were first called pericanalicular-dense bodies. "Christian De Duve" called them lysosomes in 1955. They were named as lysosomes because they contain hydrolytic enzymes. Occurence:…
DEFINITION OF MITOCHONDRIA: Mitochondria are center for cellular respiration. It converts chemical energy into kinetic energy. Information About Mitochondria In 1857 Kolliker observed mitochondria and called them as sarco-somes. Flemming called them as Fila. Altmann in 1890 called them as Bioplasts. Benda gave the name mito-chondria. Porter…
The cytoplasm of the animal cell is bounded by a thin limiting membrane called "Cell membrane". Nageli and Cramer called this membrane as cell membrane in 1855. In 1931 "Plowe" named this as plasmalemma. Modem cell biologists prefer to call it plasma membrane (According to De Robertis). Danielli &…
Cell is a fundamental, structural and functional unit of living organism. The science which deals with cells and their organelles is called cell-biology. The term cell was first used by Robert Hooke in 1665. He described the cell first as cella which means hollow space. Robert Hooke observed cells in…
Serial No. Feature Prokaryotic Cell Eukaryotic Cell 1. Nuclear envelope absent present 2. DNA single, circular and naked more than one and combined with proteins 3. Chromosome single multiple 4. Nucleolus absent present 5. Division amrtosis mitosis or meiosis 6. Ribosomes 70S(50S+30S scattered in cytoplasm 80S(60S+40S) Found attached to ER…