Chapter 1 The Study of Life The Study of Life
8/22/16
Chapter 1 The Study of Life
The Study of Life • Life exists almost everywhere on the Earth. • Earth possesses a variety of diverse life forms. • All living things have certain characteristics in common.
Characteristics of Life
• Are organized
– Know hierarchical levels of life on next slide
• Acquire materials and energy to sustain life – Sun is ultimate source of energy for all – Ex. of materials needed are O2, H2O, CO2
• Reproduce – life arises from life – Genes – units of information within the DNA – Asexual - 1 parent; offspring are clones – Sexual - 2 parents; offspring unique
• Respond to stimuli – necessary to acquire food, avoid injury & mating
• Are homeostatic – maintain constant internal environment
1
8/22/16
Characteristics of Life •Grow and develop – Growth – – Development –
• Adapt to their environment – Adaptations are features that increase an organism's chance of survival in a particular environment – Natural Selection (survival of the fittest) is the process whereby organisms better adapted to their environment tend to survive and produce more offspring. – Evolution are the changes that occur in the population over a long period of time.
Hierarchical Levels of Organization ATOM Molecules or Compounds ORGANELLES CELLS TISSUES ORGANS ORGAN SYSTEMS
ORGANISM POPULATION COMMUNITY ECOSYSTEM
BIOSPHERE
Classification of Living Things • Living organisms are assigned to groups based upon their genetic & physical similarities. • Systematics is the study of the evolutionary relationships between organisms. • Taxonomy is science of identifying and grouping organisms into categories. • Each organism is classified into the following categories – – – – – – – –
Domain Kingdom Phylum Class Order Family Genus species
MOST INCLUSIVE
LEAST INCLUSIVE
2
8/22/16
Domains • Domains - largest classification category. • Organisms are assigned to 1 of 3 domains based on biochemical & genetic evidence. – Domain Archaea – Domain Bacteria – Domain Eukarya
Domain Archaea
Domain Bacteria
• Prokaryotes - unicellular organisms that lack a membrane-bound nucleus. • Contain ribosomes • Oldest cells
• Prokaryotes - unicellular organisms that lack a membrane-bound nucleus. • Contain ribosomes • These bacteria are found almost everywhere on Earth • Many are beneficial while others are pathogens.
• Found in extreme environments – Thermophiles – Halophiles – Methanogens
– – – –
E coli (good & bad version) Lactobacilli Streptococcus Helicobacter pylori
Domain Eukarya • Eukaryotes have a membrane-bound nucleus & major organelles. • Domain Eukarya is divided into 4 Kingdoms.
3
8/22/16
Domain Eukarya Protista • Most unicellular, some multicellular • 3 nutritional methods – Protozoa heterotrophic – Algae - autotrophic – Slime molds & water molds - saprophytic
Fungi • Most multicellular; Yeast is unicellular • Heterotrophic - absorbs digestive foods • Cell walls of chitin • Body of filamentous strands called HYPHAE
Examples: paramecium, spirogyra, amoeba, slime mold, kelp,
Domain Eukarya Plantae • Multicellular • Autotrophicphotosynthesis • Cell walls of cellulose • Specialized cells
Animalia • • • •
Multicellular Heterotrophic NO cell walls Specialized cells
4
8/22/16
Categories of Classification Domain Kingdom Phylum Class Order Family Genus species
Most inclusive
Least inclusive
Scientific Names • Binomial nomenclature – 2 part scientific naming system – Genus name, species name – Genus is capitalized, species in lower case – Written in Latin – universal language – Written in italics or underlined –Examples: »Homo sapiens - man »Pisum sativum - pea »Felis domesticus - cat
5
8/22/16
The Process of Science • Biology is the scientific study of life. • The process of science uses the Scientific Method, which is
Steps of Scientific Method • • • • • • •
Observations used to determine problem Research problem Hypothesis formed Experiment to test hypothesis Observe and record data from experiment Form conclusion from data Report to other scientist
Problems, Observations & Research • Scientist are curious, ask questions and try to solve problems. • Scientist use their senses to make observations. • Scientist expand their understanding by researching other studies
6
8/22/16
Hypothesis • Tentative explanation for an observable phenomenon • Must be something that can be tested • Watch for experimenters' bias • Moral & religious beliefs not testable • Inductive Reasoning occurs when one uses creative thinking to combine isolated facts into a cohesive whole • Deductive Reasoning occurs when scientist use “if, then” logic – If I raise the temp. of a cup of water, then the amount of sugar that can be dissolved in it will increased.
Experiment • Experimentation • For an experiment to be viable, it must have several factors in place – Constants – factors that will remain the same for all test groups. – Independent variable – the part of the experiment being tested. Only 1 variable can be tested at a time. – Dependent variable –
Experiment • A experiment has 2 groups: • Control Group – goes through all the steps of the experiment but lacks the factor being tested. Is used for comparison. • Experimental Group – only 1 variable at a time can be tested. Everything else must be kept constant.
7
8/22/16
Observations & Data • Scientist make observations throughout the experiment. • Data will be all the results of an experiment. • The larger the sample size, the more reliable the results. • Data can be displayed as a graph or a table.
Conclusion & Report • Scientist analyze all data in order to reach a conclusion; can the hypothesis be supported or not. • Scientist report their findings in scientific journals to be reviewed and critiqued by their peers. • Experiments and conclusions must be repeatable. • If the results do not support the hypothesis, then it may be used to formulate an alternate hypothesis
Scientific Theory • A scientific theory is a hypothesis repeatedly supported by observations, experiments, data and conclusions.
8
8/22/16
Examples of Theories in Biology • • • • •
Cell Homeostasis Gene Evolution Biogenesis
VI. Science and Social Responsibility • Technology is the application of knowledge for a practical purpose. • Technology has both benefits and drawbacks. • Ethical and moral issues surrounding the use of technology must be decided by everyone.
Examples
• Industrial revolution introduced machines to help man do work….POLLUTION • Microbiology identified viral & bacterial diseases that caused illness. Medical fields created antibiotics & vaccines to protect us. Some now try to use this info in…. BIOLOGICAL WARFARE • Cell phones & texting allow you to stay in contact with friends & family… CAR WRECKS • Fracking increase oil production…increase in earthquakes
9
Chapter 1 The Study of Life
The Study of Life • Life exists almost everywhere on the Earth. • Earth possesses a variety of diverse life forms. • All living things have certain characteristics in common.
Characteristics of Life
• Are organized
– Know hierarchical levels of life on next slide
• Acquire materials and energy to sustain life – Sun is ultimate source of energy for all – Ex. of materials needed are O2, H2O, CO2
• Reproduce – life arises from life – Genes – units of information within the DNA – Asexual - 1 parent; offspring are clones – Sexual - 2 parents; offspring unique
• Respond to stimuli – necessary to acquire food, avoid injury & mating
• Are homeostatic – maintain constant internal environment
1
8/22/16
Characteristics of Life •Grow and develop – Growth – – Development –
• Adapt to their environment – Adaptations are features that increase an organism's chance of survival in a particular environment – Natural Selection (survival of the fittest) is the process whereby organisms better adapted to their environment tend to survive and produce more offspring. – Evolution are the changes that occur in the population over a long period of time.
Hierarchical Levels of Organization ATOM Molecules or Compounds ORGANELLES CELLS TISSUES ORGANS ORGAN SYSTEMS
ORGANISM POPULATION COMMUNITY ECOSYSTEM
BIOSPHERE
Classification of Living Things • Living organisms are assigned to groups based upon their genetic & physical similarities. • Systematics is the study of the evolutionary relationships between organisms. • Taxonomy is science of identifying and grouping organisms into categories. • Each organism is classified into the following categories – – – – – – – –
Domain Kingdom Phylum Class Order Family Genus species
MOST INCLUSIVE
LEAST INCLUSIVE
2
8/22/16
Domains • Domains - largest classification category. • Organisms are assigned to 1 of 3 domains based on biochemical & genetic evidence. – Domain Archaea – Domain Bacteria – Domain Eukarya
Domain Archaea
Domain Bacteria
• Prokaryotes - unicellular organisms that lack a membrane-bound nucleus. • Contain ribosomes • Oldest cells
• Prokaryotes - unicellular organisms that lack a membrane-bound nucleus. • Contain ribosomes • These bacteria are found almost everywhere on Earth • Many are beneficial while others are pathogens.
• Found in extreme environments – Thermophiles – Halophiles – Methanogens
– – – –
E coli (good & bad version) Lactobacilli Streptococcus Helicobacter pylori
Domain Eukarya • Eukaryotes have a membrane-bound nucleus & major organelles. • Domain Eukarya is divided into 4 Kingdoms.
3
8/22/16
Domain Eukarya Protista • Most unicellular, some multicellular • 3 nutritional methods – Protozoa heterotrophic – Algae - autotrophic – Slime molds & water molds - saprophytic
Fungi • Most multicellular; Yeast is unicellular • Heterotrophic - absorbs digestive foods • Cell walls of chitin • Body of filamentous strands called HYPHAE
Examples: paramecium, spirogyra, amoeba, slime mold, kelp,
Domain Eukarya Plantae • Multicellular • Autotrophicphotosynthesis • Cell walls of cellulose • Specialized cells
Animalia • • • •
Multicellular Heterotrophic NO cell walls Specialized cells
4
8/22/16
Categories of Classification Domain Kingdom Phylum Class Order Family Genus species
Most inclusive
Least inclusive
Scientific Names • Binomial nomenclature – 2 part scientific naming system – Genus name, species name – Genus is capitalized, species in lower case – Written in Latin – universal language – Written in italics or underlined –Examples: »Homo sapiens - man »Pisum sativum - pea »Felis domesticus - cat
5
8/22/16
The Process of Science • Biology is the scientific study of life. • The process of science uses the Scientific Method, which is
Steps of Scientific Method • • • • • • •
Observations used to determine problem Research problem Hypothesis formed Experiment to test hypothesis Observe and record data from experiment Form conclusion from data Report to other scientist
Problems, Observations & Research • Scientist are curious, ask questions and try to solve problems. • Scientist use their senses to make observations. • Scientist expand their understanding by researching other studies
6
8/22/16
Hypothesis • Tentative explanation for an observable phenomenon • Must be something that can be tested • Watch for experimenters' bias • Moral & religious beliefs not testable • Inductive Reasoning occurs when one uses creative thinking to combine isolated facts into a cohesive whole • Deductive Reasoning occurs when scientist use “if, then” logic – If I raise the temp. of a cup of water, then the amount of sugar that can be dissolved in it will increased.
Experiment • Experimentation • For an experiment to be viable, it must have several factors in place – Constants – factors that will remain the same for all test groups. – Independent variable – the part of the experiment being tested. Only 1 variable can be tested at a time. – Dependent variable –
Experiment • A experiment has 2 groups: • Control Group – goes through all the steps of the experiment but lacks the factor being tested. Is used for comparison. • Experimental Group – only 1 variable at a time can be tested. Everything else must be kept constant.
7
8/22/16
Observations & Data • Scientist make observations throughout the experiment. • Data will be all the results of an experiment. • The larger the sample size, the more reliable the results. • Data can be displayed as a graph or a table.
Conclusion & Report • Scientist analyze all data in order to reach a conclusion; can the hypothesis be supported or not. • Scientist report their findings in scientific journals to be reviewed and critiqued by their peers. • Experiments and conclusions must be repeatable. • If the results do not support the hypothesis, then it may be used to formulate an alternate hypothesis
Scientific Theory • A scientific theory is a hypothesis repeatedly supported by observations, experiments, data and conclusions.
8
8/22/16
Examples of Theories in Biology • • • • •
Cell Homeostasis Gene Evolution Biogenesis
VI. Science and Social Responsibility • Technology is the application of knowledge for a practical purpose. • Technology has both benefits and drawbacks. • Ethical and moral issues surrounding the use of technology must be decided by everyone.
Examples
• Industrial revolution introduced machines to help man do work….POLLUTION • Microbiology identified viral & bacterial diseases that caused illness. Medical fields created antibiotics & vaccines to protect us. Some now try to use this info in…. BIOLOGICAL WARFARE • Cell phones & texting allow you to stay in contact with friends & family… CAR WRECKS • Fracking increase oil production…increase in earthquakes
9
