Lectures 7 & 8: The Scope of Biology PDF

The Scope of Biology – lectures 7 &8 Core Concepts - 1 “LIFE” chapter 1 1  What is Biology? “Biology is the natural science that focuses on the study of life and living organisms, including their structure, function, developmen...

The Scope of Biology – lectures 7 &8 Core Concepts - 1 “LIFE” chapter 1 1  What is Biology? “Biology is the natural science that focuses on the study of life and living organisms, including their structure, function, development, interactions, evolution, distribution, and taxonomy.” Source: https://www.jove.com/science- education/10647/what-is-biology 2 Recap 3  Lesson objectives State and describe the relationship between biology & other disciplines State and describe different levels in which biology can be studied 4 Biology is related to other sciences 5  Life on Earth – where? Life exists everywhere on Earth, from the poles to the equator 6  Life on Earth – size? From the tiny single-celled algae to 115 m tall trees (longer than 100m race) 7  Life on Earth – size? From the tiny to the massive 8  Biologists study life at different levels Biology can be visualized as a hierarchy of units that include Atoms Molecules Cells Tissues Organs Systems Organisms Populations Communities Biosphere. 9 Levels of Organization Levels of Organization (continued) Fig. 1.1-2 8 Fig. 1.1-3 10 Uniqueness of each level Each level of biological organization has its emergent properties. Molecules have properties not found in the component atoms; Organs have properties not found in the individual tissues of which they are composed. Cells have properties not found in the individual molecules of which they are composed. 14  Atomic Level (chapt 2, 3,4) Lowest level usually studied in chemistry. The kind, quantity, arrangement of these atoms greatly influences biological structure and function. Six elements make about 99% of human body Oxygen (65%) Carbon (18%) Hydrogen (10%) Nitrogen (3%) Calcium (1.5%) Phosphorus (1.0%) 15  Molecular Level (chapt 2, 3,4) Atoms join to make molecules. Certain types of large molecules are found in all living systems. These are responsible for many biological structures and functions e.g. proteins, carbohydrates, lipids, phosphates, nucleic acids, hormones, enzymes, etc. Molecular Biology BIO308 Biochemistry BIO 307 16  Cellular Level (chapt 5,6,7) The cell is the basic building block of life Some whole organisms exist at cellular level – called unicellular Amoeba, Euglena, Paramecium etc. Cell Biology (BIO211) 17  Tissue Level Tissues are groups of cells with similar and coordinated functions. e.g. muscle, blood, xylem, epithelium, nervous, epidermal etc. Histology 18  Organ level Several different tissues are usually joined to form larger units called organs e.g. leaf, brain, flower, ovary, pancreas, kidney, lungs. Organs perform specific functions e.g. Leaf – photosynthesis, gas exchange Roots – water & mineral absorption Heart - heart pumps blood Anatomy/Physiology – Bio 214, Bio 213, Bio 218 19  Organ System Level Several organs “work” together to achieve a common purpose e.g. digestive, transport, communication, movement, sensory, nervous, endocrine, reproductive, excretory, eye, ear, Some organs may be part of several systems, performing several & different functions e.g. tongue, liver, leaf, heart, breast, 20  Organism Level An organism is a recognizable self contained individual Some are made up of only one cell, described as unicellular. Others are made up tissues only Others are made up of organs & organ systems 21  Population Level Population is … A group of organisms of the same species Organisms of the same species living in the same area & capable of interbreeding Population biology/Ecology (BIO215) 22  Community Level Community is made up of Several populations (different species) living in the same area (place) in which they interact in one or more ways All the populations living and interacting within a particular geographic area make up a biological (or biotic) community. Community Ecology (BIO215) 23  Ecosystem Level An ecosystem is the living organisms in a community together with their nonliving or abiotic environment Ecosystem may vary in size from a small drop of water to a whole ocean! Ecology (BIO215) 24  Biome Level a complex/large biotic community characterized by distinctive plant and animal species and maintained under the climatic conditions of the region, e.g. Terrestrial (land) biomes Freshwater biomes Marine biomes Major biomes of Africa Deserts, tropical forests, 25  Biosphere Level ALL biomes on earth constitute the Biosphere and exchange energy among each other. 26  Therefore Biology can be studied at several levels and in several disciplines. We have biochemistry, microbiology, physiology, cell biology, forest science, botany, ecology etc Look at the careers options in “Student Handbook and Lab Manual 2024” Which level fascinates you most? 27