Themes in Biology

Biology- the study of all living things Properties of Living Organisms 1. Cellular structure and function cell: basic unit of structure and function of organisms, capable of all life functions - covered by membranes - some organisms are unicellular or multicellular 2. Reproduction - process by which organisms make more of the same organism - essential for life since no organism lives forever

3. Metabolism- sum of all chemical reactions in an organism - sun: main source of energy for all organisms to fuel - sun: main source of energy for all organisms to fuel chemical reactions chemical reactions Ex: plants capture suns energy and make glucose Ex: plants capture suns energy and make glucose which we eat which we eat 4. Maintain homeostasis - constant internal environment in an organism - organisms must respond to external environment to survive - organisms must respond to external environment to survive Ex: arctic seals- blubber Ex: arctic seals- blubber cactus- heavy waterproof layer cactus- heavy waterproof layer

5. Heredity – passing of traits from parent to offspring - controlled by genes (proteins) on DNA - controlled by genes (proteins) on DNA - can be affected by mutations - can be affected by mutations Mutations – change in the DNA which can be harmful or beneficial Ex: sickle cell anemia Bad- rbc do not carry oxygen properly Good- give resistance to malaria sex cell mutations are passed on to offspring autosomal mutations are not passed to offspring 6. Evolution – gradual change in a species over a period of time Species: group of genetically similar organisms that can produce fertile offspring offspring Darwin- said evolution occurred through natural selection - Organisms with favorable genes survived, reproduced, - Organisms with favorable genes survived, reproduced, and passed favorable genes to offspring. and passed favorable genes to offspring. 7. Interdependence – organisms dependence on each other within an environment

Purposes of Biology To solve real world problems: A. Studying ecosystems B. Genetically engineered crops C. Help fight diseases - AIDS - Cancer - Cystic fibrosis

The Scientific Method Steps 1. Make observations and ask a question ask a question 2. Form a hypothesis (educated guess based on (educated guess based on what is already known) what is already known) - prediction: expected outcome from the test assuming the hypothesis is correct expected outcome from the test assuming the hypothesis is correct

3. Test the hypothesis thru experimentation - controlled experiment A. control group: A. control group: “normal condition” “normal condition” - receives no experimental treatment or change in condition - receives no experimental treatment or change in condition B. experimental group: B. experimental group: “test group” “test group” - variable/ experimental factor being tested for - variable/ experimental factor being tested for a. independent variable: factor being varied a. independent variable: factor being varied b. dependant variable: factor being measured b. dependant variable: factor being measured

4. Collect and analyze data - use charts, tables, observations - use charts, tables, observations 5. Draw conclusions (formation of a theory) - can support or reject hypothesis - can be disproven through further experimentation 6. Share results or retest - publish data in scientific journals

Representing Data Graphically Charts/Graphs There are three basic components to most charts/graphs: Labels- defines the data:Labels- defines the data: - title, axis titles and labels, legends defining separate data series - title, axis titles and labels, legends defining separate data series Scales- define the range of the Y and the X axisScales- define the range of the Y and the X axis Graphical elements- represent the dataGraphical elements- represent the data - bars in bar charts - lines in times series plot - points in scatter plots - slices of a pie chart

Pie Charts

Bar Graphs

Line Graphs School System Enrollment

Scatter Plots (x,y)

Scatter Plots (x,y) Rules for Scatterplots (shows relationship between variables) Use two interval-level variables (x and y)Use two interval-level variables (x and y) Fully define the variables with the axis titlesFully define the variables with the axis titles Chart title should identify the two variables and the cases (e.g., cities or states)Chart title should identify the two variables and the cases (e.g., cities or states) X axis: independent variable (cause)X axis: independent variable (cause) Y axis: dependent variable (result) Y axis: dependent variable (result) Scale the axes to maximize the use of the plot area for displaying the data pointsScale the axes to maximize the use of the plot area for displaying the data points Use same interval measurements on each axisUse same interval measurements on each axis Do NOT connect dots, use a trend lineDo NOT connect dots, use a trend line

Scatter Plot Trend Lines NEGATIVE NEGATIVE indirect indirect relationship relationship (+, -) (+, -) NULL POSITIVE NULL POSITIVE no direct no direct relationship relationship (0,0) (+, +) (0,0) (+, +)

Theory - Explanation based on a set of related hypotheses that have been tested and confirmed many times but can be broken. -Theories unite and explain a broad range of observations - Scientific theories are generally accepted as scientific principle whereas to the general public, theories are considered statements of uncertainty

Scientific Law summarizing statement that is considered fact and can not be broken summarizing statement that is considered fact and can not be broken Ex: gravity

Studying Behavior animal behavior: what an animal does when interacting with its environmentanimal behavior: what an animal does when interacting with its environment ex: humpback whale: bubble net

Designing Experiments on Animal Behavior Hypothesis based experimentsHypothesis based experiments Dutch biologist Niko Tinbergen studied digger waspsDutch biologist Niko Tinbergen studied digger wasps "How does each wasp keep track of her nests?""How does each wasp keep track of her nests?" Causes of Behavior immediate cause: explanation of an organism's behavior based on its immediate interactions with the environmentimmediate cause: explanation of an organism's behavior based on its immediate interactions with the environment ultimate cause: explanation of an organism's behavior based on its evolutionary adaptationsultimate cause: explanation of an organism's behavior based on its evolutionary adaptations Tinbergen used simple materials in his experiment—pine cones and stones— and a simple procedure. The results led him to conclude that digger wasps use a pattern of landmarks to find their nests. Tinbergen used simple materials in his experiment—pine cones and stones— and a simple procedure. The results led him to conclude that digger wasps use a pattern of landmarks to find their nests.

Types of Behavior Is it nature or nurture? innate behavior: behavior performed correctly and in the same way by all individuals of a species, without previous experience (genetic cause)innate behavior: behavior performed correctly and in the same way by all individuals of a species, without previous experience (genetic cause) fixed action pattern (FAP): innate behavior that occurs as an unchangeable sequence of actionsfixed action pattern (FAP): innate behavior that occurs as an unchangeable sequence of actions circadian rhythm: rhythmic pattern of behavior (in an animal) or biological cycle (in a plant) that follows an approximately 24-hour natural cyclecircadian rhythm: rhythmic pattern of behavior (in an animal) or biological cycle (in a plant) that follows an approximately 24-hour natural cycle The graylag goose responds to an egg outside her nest with a set of specific actions. Even when the egg is removed, the goose will continue to push at the air with her beak until she completes the FAP (fixed action pattern The graylag goose responds to an egg outside her nest with a set of specific actions. Even when the egg is removed, the goose will continue to push at the air with her beak until she completes the FAP (fixed action pattern

Interaction of Genes and Experience How does inheritance and experience form a particular behavior? Biologists mated two differentBiologists mated two different species to form a hybrid species species to form a hybrid species Conclusion: hybrid offspring could alter inherited behavior based on experience.Conclusion: hybrid offspring could alter inherited behavior based on experience.

learning: a change in an animal's behavior resulting from experiencelearning: a change in an animal's behavior resulting from experience habituation: type of learning in which an animal stops responding to a repeated stimulus that conveys little or no important informationhabituation: type of learning in which an animal stops responding to a repeated stimulus that conveys little or no important information ex: ticking of a clock imprinting: learning that is limited to a specific time period in an animal's life and that is usually irreversibleimprinting: learning that is limited to a specific time period in an animal's life and that is usually irreversible critical learning period : time period in which imprinting takes place

Lorenz: greylag goose experiment Groups Groups control: mother rears young in nest experimental: Lorenz rears young in incubator result: Control group: normal imprinting, followed mother, had normal goose relationships Experimental group: imprinted on Lorenz, followed him, prefered human relationships to geese

Conditioning: learning that a particular stimulus or a particular response is linked to a reward or punishmentConditioning: learning that a particular stimulus or a particular response is linked to a reward or punishment Ex: Pavlov’s dogsEx: Pavlov’s dogs operant conditioning: trial and error learning Insight: the ability to respond appropriately to a new situation without previous experienceInsight: the ability to respond appropriately to a new situation without previous experience

Social Behaviors Competitive Behaviors (pack animals)Competitive Behaviors (pack animals) aggressive behavior: symbolic threat display or a physical struggle between individuals of the same species dominance hierarchy : ranking of individuals in a group based on aggressive behavior territorial behavior: behavior that protects territorial rights ex: chatting squirrels ex: chatting squirrels marking areas with urine

Social Behaviors courtship ritual: elaborate behavior of individuals of the same species before matingcourtship ritual: elaborate behavior of individuals of the same species before mating ex: fanning of tail feathers by a peacock may indicate good health communication: signals among animals that include sounds, odors, visual displays, and touchescommunication: signals among animals that include sounds, odors, visual displays, and touches Von Frisch and later researchers determined that the angle of a returning honeybee's "waggle dance" signals the direction of the food source from the hive compared to the position of the sun

Measurement “Eventually we will have to exchange our feet for meters”

Measurement System International (SI)System International (SI) - standardized system of measurement - based on the number 10 - France, late 1700’s

SI Prefixes