CHAPTER 1 THE SCIENCE OF LIFE

Transcription

1 CHAPTER 1 THE SCIENCE OF LIFE

2 Biology Bio - life Logy- the study of Biology is the study of life or living things Some branches of Biology include- Microbiology, Marine Biology, Botany, Zoology, Ecology

3 Organisms An organism is a living thing such as plants or animals

4 Characteristics of Living Things 1. Made of cells 2. Organization- the high degree of order within an organism s internal and external parts and in its interactions with the living world

5 Pictures

6 More pictures Tissue Organ

7 Organ Organ Systems

8 Characteristics of Living Things 3. Respond to stimuli - a physical or chemical change in the internal or external environment. 4. Have the ability to reproduce 5. Uses energy for growth and maintenance. (Metabolism)

9 Characteristics of Living Things 6. Growth and development. Organisms grow by cell division and cell enlargement. 7. Have adaptations to help them survive and carry out homeostasis. 8. Homeostasis the ability to maintain normal internal conditions Ex: sweating when it is hot to maintain 98 body temperature

10 HOG RACER Homeostasis Organized Growth and development Reproduce Adaptations Cells Energy Respond to stimuli

11 CHECK IT! Turn your notes over and without looking, turn to your table partner and together, come up with as many parts of HOG RACER as you can. If you think you have all 8 and can say them to the class, stand up as quickly as possible!

12 Themes In Biology 1. Diversity and Unity of Life a. Diversity or differences: there are millions of species of organisms

13 Themes In Biology b. Unity: features that all organisms have in common (Ex: DNA and organelles)

14 Themes In Biology c. Tree of Life Model: the relationships by ancestry among organisms Three Domains (Bacteria, Archaea, & Eukarya) Six Kingdoms (Bacteria, Archaea, Protists, Plants, Fungi, and Animals)

15 Themes In Biology 2. Interdependence of Organisms a. Ecology: the branch of biology that studies organisms interacting with each other and the environment. Ex. Desert biome

16 Themes In Biology b. Scientists can study a single species or they may study ecosystems which are environmental communities of living species

17 Themes In Biology 3. Evolution of Life a. Populations of living organisms change over time, or evolve. b. Evolution is the process in which inherited traits within a population change over many generations.

18 Evolution: Darwin s Finches

19 Themes In Biology c. According to the theory of evolution by Natural Selection organisms with favorable traits are better able to survive and reproduce successfully than organisms that lack these traits.

20 Themes In Biology d. Adaptations are traits that improve an organism s ability to survive and reproduce.

21 CHECK IT! Turn your notes over and without looking, turn to your table partner and together, briefly review the three themes in biology.

22 Scientific Method The scientific approach to solving a problem; logical and orderly

23 The Steps 1. Define the problem 2. Collect information or data a) Observation b) Measurement c) Scientific sampling d) Organize data (graph/table) 3. Form a hypothesis; a proposed (possible) solution to the problem or an educated guess

24 The Steps 4. Design an experiment to test your hypothesis 5. Analyze the data and form a conclusion Analysis is done to determine whether data: - support or refute a given hypothesis - are reliable

25 The Steps 6. Data and conclusions are then communicated to scientific peers and to the public. Ex: publishing results in scientific journal

26 Controlled Experiment A controlled experiment compares an experimental (test) group and a control group and only has one variable A control group provides a normal standard against which the biologist can compare results with the experimental group

27 Controlled Experiment An experimental group is identical to the control group except for one factor, the manipulated or independent variable. ***Other variables that may affect the outcome of the experiment should be the SAME in both control and experimental groups

28 Review

29 Review Question # 1 Inference #1: Chocolate may cause pimples Formal Hypothesis: If you eat chocolate then you will get pimples. Independent Variable: Dependent Variable:

30 Review Question #2 Inference #2: Salt in soil may affect plant growth Formal Hypothesis: If there are high amounts of salt in plant soil then it will affect plant growth Independent Variable: Dependent Variable:

31 Review Question #3 Inference #3: Plant growth may be affected by the color of the light. Formal Hypothesis: If a plant is exposed to different color light then plant growth will be affected Independent Variable: Dependent Variable:

32 Review Question #4 Inference #4: Bacterial growth may be affected by temperature Formal Hypothesis: If bacteria is exposed to high temperatures then bacteria will grow at a faster rate Independent Variable: Dependent Variable:

33 Review Question #5 Inference #5: Ultraviolet light may cause skin cancer. Formal Hypothesis: If you are exposed to high amounts of ultra violet light then you are more prone to skin cancer. Independent Variable: Dependent Variable:

34 Review Question #6 Inference #6:Temerature may cause the leaves to change color. Formal Hypothesis: If leaves are exposed to varying temperatures then it will cause them to change color. Independent Variable: Dependent Variable:

35 Check It! With your table partner, describe what a control group is and what an experimental group is. Make your own example of a controlled experiment. One partner stand up if you are willing to share your example.

36 Metric System and Measurement Tools and Techniques Chapter 1 Section 4

37 Units of Measurement What is measurement? The process of determining dimensions or the quantity of something by comparing it to a measurement unit.

38 The Metric System The metric system is also called the International System of Units or SI It is a single unified system that is used in nearly every country in the world. This includes the scientific community The English system uses feet, inches, pounds, and quarts.

39 The Metric System Scientists use this system because The units were derived scientifically. The units are based on the powers of 10 so they are easier to convert from one unit to another.

40 What are the basic units of the Metric System?

41 Units of Measurement * Length * Volume Base Unit = Meter Base Unit = Liter * Temperature Base Unit = Celsius * Time Base Unit = Second * Mass Base Unit = Gram

42 KILO 1000 Units 1 2 HECTO 100 Units Ladder Method DEKA 10 Units 3 Meter s Liters Grams DECI 0.1 Unit CENTI 0.01 Unit MILLI Unit How do you use the ladder method? 1 st Determine your starting point. 2 nd Count the jumps to your ending point. 4 km = m Starting Ending Point Point How many jumps does it take? 3 rd Move the decimal the same number of jumps in the same direction = 4000 m

43 The Microscope Scientist use microscopes to reveal details that otherwise might be difficult or impossible to see Biologist use them to study organisms and their parts

44 Simple Microscope The simple microscope: a single lens microscope is used to produce an enlarged image.

45 Compound Microscope Compound Microscope- shines light through specimen and has at least two lenses to magnify an image.

46 The Development of Light Microscopes Compound light microscopes can magnify objects up to 2,000 times.

47 The Microscope To determine magnification (the increase of an object s apparent size), you multiply the: ocular lens power X objective lens power = power of magnification Power of magnification is the degree of enlargement (how many times will the object be multiplied?)

48 The Microscope Resolution is the ability of the microscope to deliver a clear image Using a light from a compound microscope limits the resolution **the higher the magnification the lower the resolution

49 The electron microscope was invented in the 1940s. This microscope uses a beam of electrons to magnify structures up to 500,000 times their actual size. Development of Electron Microscopes

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51 Scanning Electron Microscopes (SEM) Scanning Electron Microscope - passes beams of electrons over the specimen s surface and provides a 3D image that is magnified up to 100,000 times. The scanning electron microscope scans the surface of cells to learn their three dimensional shape.

52 SEM Pictures Ant Eye & Flea

53 Red Blood Cell, Platelet, & T-Lymphocyte

54 Pollen

55 Transmission Electron Microscope (TEM) Transmission Electron Microscopetransmits a beam of electrons through a very thinly sliced specimen. Has great resolution of internal structures Can magnify objects up to 200,000 times. The transmission electron microscope (TEM) allows scientists to study the structures contained within a cell.

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57 S u l f u r Influenza B a c t e r i a

58 Compound Light Microscope Electron Microscopes 1. beams of light beams of electrons 2. glass lenses electromagnetic lenses view on a florescent 3. view through ocular screen or photographic lenses plate can only view dead 4. can view living things things X 500,000X

59 Father of Microscopy Anton Van Leeuwenhoek ( ) known to have made over 500 "microscopes," of which fewer than ten have survived to the present day. These typically magnified between 20 to 30 times. He discovered blood cells, and was the first to see living sperm cells of animals. He discovered microscopic animals.

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61 1. body tube - holds the eyepiece and connects it to the objectives. 2. nosepiece it holds the objectives. 3. low objective lens- 4x magnification 4. medium objective 10x magnification 5. high objective 40x magnification

62 6. stage clips - hold the slide in place. 7. diaphragm - controls the amount of light going through the aperture. 8. light or mirror - makes the specimen easier to see.

63 9. eyepiece - where you look through to see the image of your specimen. 10. arm - part of the microscope that you carry the microscope with. 11. stage - the specimen/slide is placed on the stage for viewing.

64 12. coarse adjustment knob - used for focusing the specimen 13. fine adjustment knob - used to fine-tune the focus of your specimen after using the coarse adjustment knob.