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Biology. Study of life. Goals of Science. Investigate and understand nature Explain events in nature Use explanations to make predictions. Organized way of using evidence to learn about the natural world. Scientist assume that the universe is a system in which basic natural laws apply.
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Biology Study of life
Goals of Science • Investigate and understand nature • Explain events in nature • Use explanations to make predictions
Organized way of using evidence to learn about the natural world. Scientist assume that the universe is a system in which basic natural laws apply. Science
Qualities of a scientist • Open-Mindedness – willing to accept different ideas that they may not agree with. • Skepticism – Question existing ideas and hypothesis, and they refuse to accept explanations without evidence. • Curiosity • Creativity
Curiosity • A curious researcher, for example, may look at a salt marsh and immediately ask, “What’s that plant? Why is it growing here?” • Often, results from previous studies also spark curiosity and lead to new questions.
Skepticism • Good scientists are skeptics, which means that they question existing ideas and hypotheses, and they refuse to accept explanations without evidence. • Scientists who disagree with hypotheses design experiments to test them. • Supporters of hypotheses also undertake rigorous testing of their ideas to confirm them and to address any valid questions raised.
Open-Mindedness • Scientists must remain open-minded, meaning that they are willing to accept different ideas that may not agree with their hypothesis.
Creativity • Researchers need to think creatively to design experiments that yield accurate data.
Biologist Study • Study Diversity of Life (ex. Jane Goodall studies “ How chimpanzees behave in wild”) • Research Disease • What causes disease? • How does body fight disease? • Develop vaccines • New medicines • Develop technologies • “bionic” hand • Store and transport blood plasma for transfusions-saved countless soldiers life WWII. • Improve Agriculture • Preserve the environment
Chapter 1 Biology Life
Characteristics Of Living Things LIVING THINGS….. • made of cells • based on universal genetic code • reproduce • grow and develop • adjust to their surroundings--respond • adapt and evolve • obtain and use energy-metabolism • maintain stable internal environment
Living Things Are Organized Composed of one or more cells that are based genetic code. Organization: an arrangement of parts (cells) for the performance of the functions necessary to life
Organisms Number of Cells • Multicellular – Organisms made of many cells (cells specialized to perform different functions) (ex. monkey and trees) • Unicellular – One cells organisms ( ex. Amoeba)
Types of Cells Prokaryotes – an organism, characterized by the absence of a nuclear membrane and by DNA that is not organized into chromosomes. (ex. bacteria) Eukaryotes – an organism composed of one or more cells containing visibly evident nuclei and organelles (ex. plants and animals)
Living Things Make More Living Things Reproduction: Production of an offspring by an organism. Species: Organisms that can interbreed and produce fertile offspring in nature. (Reproduction is not essential for an individual organism, but for continuation of a species)
Types of Reproduction • Sexual – Requires two parents and offspring are not identical • Asexual – Requires one parent and offspring identical
Living Things Change During Their Lives single cell grows and takes on the characteristics of its species. Growth: Increase in the amount of material and formation of new structures in an organism. Development: All of the changes that take place during the life of an organism.
Living Things Adjust to Their Surroundings Environment: Living and nonliving surroundings to which an organism must constantly adjust (air, water, weather, temperature, other organisms, other factors) Stimulus: Any condition in the environment that requires an organism to adjust Response: A reaction to stimulus
Homeostasis Organism’s regulation of its internal environment to maintain conditions suitable for survival.
Obtain and use materials and energy Used to grow, develop and reproduce Metabolism-chemical reactions through which an organism builds up or breaks down materials.
Living Things Adapt and Evolve Adaptation: Evolution of a structure, behavior, or internal process that enables an organism to respond to stimuli and better survive in an environment. Evolution: Gradual accumulation of adaptations over time.
DO NOW: Have you or a close relative ever collected a particular item? How did you/they organize their collection?
Classification Grouping of ideas, things, etc. on the basis of similarities Ex. Classifying trees as plants, or classifying horses as animals
Classification • Taxonomy-Branch of biology that deals with the classification of living things. • Taxonomist-A person who works at or studies taxonomy
What is a Classification System?A classification system is a way to identify an organism and place it into the correct group of related organisms (similar characteristics)
Classification History • Aristotle (2000 years ago) • 1st attempt to classify • All organisms two groups-Kingdoms • Animalia • Plantae • Ernest Haeckel (1866) • Proposed 3rd Kingdom-Protista • All organisms that did not fall under plantae or animalia • Eg. Euglena-had characteristics of both plants and animals • As scientist learned more, more Kingdoms added
Classification History cont. • Kingdom Fungi was proposed • Organisms from this kingdom were originally classified as plants, but fungi are not photosynthetic and are heterotrophic, so they became part of separate Kingdom. • Robert Whittaker(1969) • Proposed 5 Kingdom Classification based upon the following: • Number of cells • Presence or absence of a nucleus • Mode of nutrition
Classification Today • 6 Kingdom Classification • Kingdom Animialia • Kingdom Plantae • Kingdom Fungi • Kingdom Protista • Kingdom Bacteria or Monera or Eubacteria • Kingdom Archaea or Archaeabacteria
6 Kingdoms-3 Domains of Life • Domain Bacteria-Kingdom Bacteria or Monera • Domain Archaea-Kingdom Archaebacteria or Archaea • Domain Eukarya (derives from Eukaryotic-Nucleus)-KindgomsAnimalia, Plantae, Protista and Fungi • Note- Domains are the largest group of classification; Kingdoms are just below domains
Kingdom Animalia • Multicellular • Contain specialized tissues and cells • Heterotrophic (obtain food from outside) • Motile • Eukaryotic • Reproduce sexually (higher animals) and asexually (lower organisms) • 2 groups • Invertebrates- without backbone • Vertebrates- with backbone
Kingdom Fungi • Unicellular or multicellular • Heterotrophic (obtain food by absorption) • Non motile • Reproduction both sexual and asexual • Saprophytic (nourishment from dead or decaying organisms) or parasitic (feed on others) • Made up of Hyphae/mycelium (mass of hyphae) • Eukaryotic • Cell walls of chitin (skeletal like material) • Ex. Unicellular=yeast; multicellular=mushroom
Kingdom Protista • Unicellular • Colonial (living in groups) or multicellular • Autotrophic (euglena) and heterotrophic (by ingestion) • Some are motile • Eukaryotic • Ex paramecium, euglena, volvox and amoeba
Kingdom Bacteria or Monera • Unicellular • Asexual • Prokaryotic (no true nucleus) • Some Saprophytic or parasitic • Autotrophic or heterotrophic • Microscopic • Non-motile and motile • Motile by means of flagellum • 3 shapes • Round-Coccus (cocci-plural) • Spiral- Spirillus (spirilli-plural) • Rod- Bacillus (bacilli-plural)
Kingdom Plantae • Multicellular • Contain specialized tissues and cells • Photosynthetic • Autotrophic (make own food) • Non-Motile or sessile (non moving) • Eukaryotic • Reproduce sexually and asexually • Cell Walls made of Cellulose (carbohydrate) • Divided into 2 groups-Flowering and non-flowering
Kingdom Archaea or Archaebacteria • Similar to bacteria • Survive in extreme environments (volcanoes, hot springs, ocean vents) • Biochemically and genetically different from bacteria • Has same shapes as other bacteria • 3 types: • Methanogens- Produce methane • Halophiles – “salt loving” bacteria • Thermophiles – “heat loving” bactera.
Modern Taxonomy Taxonomy done today: Sorting and grouping of organisms based upon similar characteristics