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BIOLOGY – DIVE INTO LIFE Mycareers.Pk 2019 BIOLOGY – DIVE INTO LIFE mycareers.pk TAHIR HABIB ANFAL ACADEMY PREFACE Biology is a natural science concerned with the study of life and living organisms including their function , Structure , growth , evolution , distribution , identification and Taxonomy. Modern Biology is vast and eclectic field composed of many branches and sub disciplines. ‘ Biology is the most powerful technology ever created. DNA is software, protein are hardware, cells are factories.’ -- Arvind Gupta This brief book can be used by teachers and students in Biology field Specially this book is meant for students of S.S.T , SDO Wildlife , Matriculation F.Sc, B.Sc., B.S(Hons.) of biological group. Students appearing in exams of S.S.T Science in Education department may be immensely benefited by this book. This book has been written strictly according to syllabus of H.E.C. It is copied from different sources mostly from Zoology of Miller and Harley, and extra material is also included. I am highly thankful to my Friends Shahnawaz Silachi & Abdul Hameed Korai . who means a lot for me because their inspiration always remained encouraging for me. mycareers.pkI am also thankful to Mr. Adnan Jaskani C.E.O of Anfal Academy I dedicate my this brief book to Students of Anfal and every student of Balochistan .I am sure this book will prove to be an invaluable asset for the students and teachers. To enhance your concept in Biology please study 1: Campbell Biology By Jane B Reece 2: Biology By Raven & Johnson 3: Zoology by Miller and Harley 4: Integrated principles of Zoology by Hickman 5: Biology by P.S Verma and Agarwal, and study three Books A.B.C Zoology and Botany for B.Sc. I shall feel highly obliged if suggestions for the improvement of the book are brought to my notice, so that future edition of the book may become more useful. TAHIR HABIB ASSISTANT DIRECTOR (BF&CDA) [email protected] 2 | P a g e Biology is the most powerful technology ever created. DNA is software, protein are hardware, cells are factories. ------ Arvind Gupta Biology is the study of complicated things that have the appearance of having been designed with a purpose. ------ Richard Dawkins I believe God controls the universe. I don’t believe Biology works in an mycareers.pkuncontrolled fashion. ------ Richard Mourdock A cell is regarded as a true biological atom. ------ George Henry Lewes 3 | P a g e TABLE OF CONTENTS SNo. TOPICS/SUBHEADINGS Page No. 1. BIOLOGY – INTRODUCTION – BRANCHES OF BIOLOGY - BIOLOGISTS 5-10 2. CELL - INTRODUCTION – ORGANELLES OF CELL – CELL DIVISION – MITOSIS , MEIOSIS 11-12 3. TAXONOMY – CLASSIFICATION - BINOMIAL NOMENCLATURE 4. VIRUS -- STRUCTURE OF VIRUS – DISEASES -- 13-15 5. BACTERIA – STRUCTURE – IMPORTANCE OF BACTERIA - PATHOGENIC BACTERIA-- 16-18 CYANOBACTERIA 6. ALGAE: TYPES OF ALGAE – CYANOPHYCEAE 19-22 7. FUNGI : CHARACTERISTICS , GILLED FUNGI 23-24 8. PLANTS : CHARACTERISTICS , CLASSIFICATION , BRYOPHYTES , PTERIDOPHYTES, 25-36 TRACHEOPHYTES , LIFE CYCLES , FERNS , MOSSES , MARCHANTIA , PHOTOSYNTHESIS 9. ANIMALIA – INVERTEBRATES, CLASSIFICATION , CHARACTERISTICS , PROTOZOA , 37-43 PORIFERA , COELENTERATE , PLATYHELMINTHES , NEMATODS , ANNELIDA , ARTHROPODS , MOLLUSC , ECHINODERMS , LOCOMOTION AND OTHER PROCESSES 10. ANIMALIA – VERTEBRATES – CHARACTERISTICS , CLASSIFICATION , PICES , AMPHIBIANS , 44-50 REPTILES , BIRDS , MAMMALS 11. GASEOUS EXCHANGE IN PLANTS AND ANIMALS 51-55 12. TRANSPORT OF MATERIALS IN LIVING THINGS, DIFFUSION , OSMOSIS , TRANSPIRATION. 55-58 13. CIRCULATORY SYSTEM – BLOOD , PLASMA , BLOOD CELLS. KIDNEY 58-63 14. CONTROL & COORDINATION – NERVES SYSTEM , BRAIN 63-67 15. ENDOCRINE GLAND - PITUITARY GLAND - THYROID GLAND – PANCREAS – ADRENAL - 67-72 mycareers.pkTESTES IN MALES - OVARIES IN FEMALES 16. REPRODUCTION IN PLANTS AND ANIMALS- ASEXUAL AND SEXUAL REPRODUCTION 73-80 17. DEVELOPMENT OF FROG-EMBRYONIC DEVELOPMENT – CLEAVAGE – MOROLA- 81-84 BLASTULA - GASTRULA – NEURULATION: 18. EVOLUTION – THEORIES OF EVOLUTION 85-87 19. INHERITANCE AND GENETIC CROSSES 88-96 20. ENVIRONMENT SCIENCE – ECOSYSTEMS , BIOGEOCHEMICAL CYCLES , POLLUTION , 97-106 GREEN HOUSE , GLOBAL WARMING , ACID RAIN 21. DISEASES AND PATHOGENS 106-109 22. Glossary 110-145 4 | P a g e BIOLOGY – Introduction • Bio – means life • Ologos – to study / the study • BIOLOGY – is the study of life / the study of living things • Biologist – the person who studies Biology 2. • Aristotle – Greek philosopher; first who classified living things as to air, land, or water dwellers; Father of Biology 3. • Galen – Greek physician; first to dissect apes and pigs; Father of Anatomy 4. • Andreas Vesalius – made the first dissection on human anatomy; discovered Comparative Anatomy 5. William Harvey – showedconclusively that the heartpumps blood and the bloodcirculates 6. • Marcello Malphigi – Italian physician & anatomist, founder of microscopic anatomy 7. • Anton Van Leeuwenhoek first to use microscope; discovered microorganisms such as protozoans called animalcules 8. • Charles Darwin – wrote the book On the Origin of Species By Means of Natural Selection mycareers.pk 2 Major Divisions of Biology • Botany – the study of PLANTS • Zoology – the study of ANIMALS Study of trees and their Dendrology Study of fungi and some Mycology Study of fossil plants Paleonbotany Study of diseases of Phytopathology Study of cultivating fruits Pomology Arachnology Study of single class of invertebrate (scorpions, spiders, etc.) Conchology Study of mollusks Embryology Study of the development of animal forms Entomology Study of insects 5 | P a g e Herpetology Study of reptiles Mammalogy Study of mammals Ornithology Study of birds Ichthyology Study of fishes Anatomy – the study of structures of entire organisms and their parts Physiology – the study of how the body and its parts work Ecology – studyof how organisms interact with their environment &with other organisms Parasitology – the study of the organisms that live in or on other organisms that caused diseases Taxonomy – the study of the classification & evolutionary interrelationships among organisms Embryology – study of the development & growth of organisms Cytology – the study of the structures & functions of cells Microbiology – the study of microorganisms such as bacteria, protozoans, and viruses Paleontology – the study of fossils, the preserved remains and traces of organisms from the past Genetics – the study of how traits are inherited & passed on one generation to the next Morphology – the study of gross structures & forms of organisms Histology – study of tissues mycareers.pk CELL What is a cell? Cells are the basic building blocks of living things. The human body is composed of trillions of cells, all with their own specialised function. Cells are the basic structures of all living organisms. Cells provide structure for the body, take in nutrients from food and carry out important functions. Our cells contain a number of functional structures called organelles. These organelles carry out tasks such as making proteins, processing chemicals and generating energy for the cell. Cells: 6 | P a g e Cells are the basic building blocks of all living things. The human body is composed of trillions of cells. They provide structure for the body, take in nutrients from food, convert those nutrients into energy, and carry out specialized functions. Cells also contain the body’s hereditary material and can make copies of themselves. CELL THEORY Cells are the basic unit of life. The Cell Theory states that: 1) All organisms are made up of one or more cells and the products of those cells. 2) All cells carry out life activities ( require energy, grow, have a limited size). 3) New cells arise only from other living cells by the process of cell division. mycareers.pk THE THREE MAIN COMPONENTS OF ANY PLANT OR ANIMAL CELL ARE: 1. PLASMA MEMBRANE/ CELL MEMBRANE Structure- a bilipid membraneous layer composed of proteins and carbohydrates. It is fluid like. Function - the cell membrane separates the cell from its external environment, and is selectively permeable (controls what gets in and out). It protects the cell and provides stability. Proteins are found embedded within the plasma membrane, with some extending all the way through in order to transport materials. Carbohydrates are attached to proteins and lipids on the outer lipid layer. 7 | P a g e 2. CYTOPLASM Structure - The jelly-like substance composed of mainly water and found between the cell membrane and nucleus. The cytoplasm makes up most of the "body" of a cell and is constantly streaming. Function - Organelles are found here and substances like salts may be dissolved in the cytoplasm. 3. NUCLEUS Structure - The largest organelle in the cell. It is dark and round, and is surrounded by a double membrane called the nuclear envelope/membrane. In spots the nuclear envelope fuses to form pores which are selectively permeable. The nucleus contains genetic information (DNA) on special strands called chromosomes. Function - The nucleus is the "control center" of the cell, for cell metabolism and reproduction. THE FOLLOWING ORGANELLES ARE FOUND IN BOTH PLANT AND ANIMAL CELLS. 1. "ER" OR ENDOPLASMIC RETICULUM The Endoplasmic Reticulum is a network of membranous canals filled with fluid. They carry materials throughout the cell. The ER is the "transport system" of the cell. There are two types of ER: rough ER and smooth ER. Rough Endoplasmic Reticulum is lined with ribosomes and is rough in appearance and smooth endoplasmic reticulum contains no ribosomes and is smooth in appearance. 2. RIBOSOMES
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