“The Study of Life” Chapter 1
I. What is Biology? A. Biology - the study of living things/ organisms
Characteristics of Living Organisms 1. Reproduce 2. Respond (adjust) 3. Adapt & Evolve 4. Metabolize (use or make food) 5. Respiration (gas exchange) 6. Grow/Develop 7. Highly organized (exp cells)
1. Atoms and Molecules Organization of living things - “organisms”
2. Cells - “basic unit of life” Human embryonic stem cells grown at the University of Wisconsin-Madison randomly changed into cell types found in the A) gut B) brain C) bone marrow D) cartilage E) muscle F) kidney Scientists haven't learned to control the development. ©1998 Science. Courtesy University CommunicationsUniversity Communications u_o_vMzpwCFQoMDQodezTCJQ
3. Tissues - group of specialized cells
4. Organs - group of specialized tissues
5. Organ Systems - specific organs
6. Organism - all organ systems working together “ a single living thing”
7. Population/Species- group of organisms that can interbreed and produce offspring. 8. Community - various populations, multiple species 9. Ecosystem - various communities and their interactions with abiotic/nonliving or physical environment around them p397 Levels-of-35665
10. Biosphere - all organisms and the environment they live in, both living and nonliving factors
Structure & Function Structure – shape or form Function – what it does Exp: Nerve cell Blood cell
Homeostasis – “steady state” maintenance of organisms internal environment Negative feedback – tends to return organism/system to its original state (homeostasis). Exp: Exercise ( Temp) Cold ( Temp)
The process of identifying new and interesting things about nature requires scientists to ask questions, make observations and try to explain things they observe. 1.Observation : use senses or tools to gather information. 2.Question: 3.Hypothesis : “Educated Guess” derived from observation. 4.Experiment : test the hypothesis, collect and analyze data. 2 Forms of Data : Quantitative – numerical values (SI) Qualitative – descriptive research, purely observational 5. Conclusion : Judgment or explanation made based on observations/data collected throughout the experiment. –State whether experiment proves or disproves the hypothesis Scientific Method ml
Keys to a good Experiment 1. Controlled (constants) –2 groups: control and experimental 2. Design a)Independent variable - condition that is changed in an experiment and effects the outcome of that experiment (what was changed, or manipulated) b) Dependent Variable - second conditions that result from change in the independent variable. (outcome of the change, exp data….measured and observed)
Tools 1.Compd light microscopes – uses light to magnify living or preserved specimens, 2D images 2.SEM – e-’s deflect off of specimens, 3D images 3.TEM – e-’s pass through specimens, 2D image/high magnification. 4.Computer based technology -models used to study complex systems that can’t be studied directly (spread of avian flu) -given rise to new areas of study…genomics
Your Knowledge of Biology Can help you make informed decisions that impact your health and the health of the environment around you. Biotechnology- the use and application of living organisms or other biological systems in the manufacture of products. (yeast…bread) Transgenic – genetically modified organisms, contain one or more genes from another species. -Exps: insect/diesease and drought resistant crops, rBGH/rBST etc. Molecular genetics – study and manipulation of DNA and genes on a molecular level.