Science 10 Unit C: Biology - Flow of Matter in Living Systems Notes PDF

Science 10 Unit C: Biology Flow of Matter in Living Systems 1 Chapter 1 Lesson 1.1: Development of Cell Theory ______________________________ ______________________________, the idea that life could emerge spontaneously Spontaneous ge...

Science 10 Unit C: Biology Flow of Matter in Living Systems 1 Chapter 1 Lesson 1.1: Development of Cell Theory ______________________________ ______________________________, the idea that life could emerge spontaneously Spontaneous generation from non-living matter, was widely accepted from the time of Romans to the 19th century. Sweaty underwear and husks of wheat in an open jar will turn into mice after 21 days. Raw meat left in a jar to rot, will spontaneously turn into maggots and flies. Redi Francesco ____________ (1668) Redi questioned the spontaneous generation of maggots from raw meat. laid eggs o He hypothesized that the flies __________ _____________ in the rotting meat instead. ids Redi set out jars containing raw meat and used different _________ to control access to the meat. open lids and others were covered in _________________________. sealed o Some of the flasks were left ____________ to the air, some were _______________ with cheesecloth o Maggots only appeared in the flasks that were left open to the air meaning the flies had direct access to the meat. ____________________ the success of Redi’s experiment, the idea of spontaneous generation Despite thrive continued to ____________________. Needham John _________________________ (1745) did John Needham wanted to prove that spontaneous generation _________ indeed exist. boiled Needham ____________________ chicken broth in a flask, allowed it to _______________ and cool sealed then ____________________ the flask with a stopper. o He observed that micro-organisms still appeared. Needham believed he had proven spontaneous generation. ife force He suggested there was a “________________________” that produced a spontaneous generation. 2 Lazzaro _________________________ (mid 1700’s) Spallanzani Spallanzani was unconvinced by Needham’s experiment. He believed that micro- organisms present in the ________ air caused the new growth. Spallanzani repeated Needham’s experiment, but made some changes: o Spallanzani used __________ flasks, boiling broth in both. two He sealed one of the flasks and ____________________ the air out of it. sealed He left the other flask _______________ to the air. o The flask left open to the air had open growth and the sealed one did not. o People still supported the idea of spontaneous generation however, insisting he had simply proven that you need ________ air for spontaneous generation to occur. Tasteur Louis ____________________ (1864) end Pasteur’s experiment brought an __________ to the acceptance of spontaneous generation. Similar to Needham and Spallanzani, Pasteur boiled broth in a flask to kill any micro- organisms. 5 o However, Pasteur’s flask had an _________________________ shaped neck. The bend prevented dust and micro-organisms from getting through to the broth but air could still make its way in. o Nothing grew in the broth. removed tipped o If the neck was ___________________, or the flask _________________ so that the broth could touch the neck (becoming contaminated), mold was observed to grow over time. 3 Characteristics of an Experiment Control ____________________ Group – used as a baseline with which to compare experimental groups. o Redi used an open jar as a control group in his experiment. Controlled ____________________ Variables – conditions that are held constant throughout an experiment. o Establishes ______________________ by isolating the effect of a manipulated variable. causality o In every trial, Redi used the same type/size of jar; he used the same type of meat, in the same amount and placed all of the jars in the same location to maintain equal temperature, amounts of light, humidity, etc. Manipulated _______________________ Variable – a condition deliberately ________________ in an experiment. changed o The only variable that Redi changed was access to air (i.e. type of lid on the jar). ____________________ Variable – a condition that changes in response to the manipulated variable. Responding o Redi observed whether or not flies appeared. Example 1 Identify each of the variables in Pasteur’s experiment. Controlled: type of flask type of broth temp humidity light etc Manipulated: S shaped neck Responding: was there new growth 4 Development of Cell Theory nucleus In 1833 a Scottish microscopist, Robert Brown, identified the ____________________ of a cell. Schleiden and Schwann (1838) Schleiden observed that all ________________ were composed of cells and he proposed the nucleus plants development was in fact the structure responsible for the ______________________________ of the rest of the cell. Schwann was studying ____________________ __________________________________ at the time. animal physiology Schleiden discussed his work with Schwann who was then able to identify the _________________ in animal cells. nuclei Schwann suspected there must be _________________________ between plant and animal tissues. similarities Schleiden and Schwann proposed that all plants and animals are composed of _______________ and that the cell was the basic unit of all organisms. cells Over time the contributions of other scientists led to our current _____________ _______________. cell theory Current Cell Theory (1830’s) All living organisms are made up of one or more _______________ and the materials produced by these cells. cells All life functions take place _____ cells, making them the ______________________ unit of life. in smallest cell division All cells are produced from pre-existing cells through the process of _________ __________________. 5  Lesson 1.2: Early Microscopes and Microscopists _______________________: an instrument with a lens or system of lenses used to magnify specimens. Microscope _______________________: a person trained in the use of a microscope. Microscopist Hans and Zacharias Janssen (1595) Hans and Zacharias are said to have developed the first ____________________ microscope. compound ocular A two-lens system that consisted of an _________________ lens and an __________________ lens. objective It had a magnifying power of approximately 20x. Antoni van Leeuwenhoek (late 1600’s) _______ ________________________________________ experimented with grinding van Leeuwenhoek lenses from high quality glass and diamonds to make simple, single lens microscopes that worked like a very powerful magnifying glass. His contributions allowed people to observe a previously unknown ______________________ world, totally invisible to the naked eye. microscope Van Leeuwenhoek made very detailed drawings of what he saw. These were the first observations of individual free-living cells and animalcules he called these cells “_______________________” (later identified as bacteria). His microscope had a magnification of approximately 250x. Robert Hooke (1665) Hooke ______________ used a handmade, three lens microscope that consisted of the ________________ lens, the ________________ lens, and the ________________ lens. ocular field objective He was the first person to see an individual __________. cell He coined the term “cell” while looking at thinly sliced pieces of __________. cork o He described individual pockets that looked like little rooms. o He called them “cells” from the Latin cella, meaning “____________ ____________”. small room 6 Compound Light Microscope Modern microscopes use _______________ to illuminate the object being viewed. ight ______________________ microscopes use more than one lens and have a much stronger Compound magnification than early microscopes. Can magnify object 400 to 1000 times its normal size 2x EYELE 25 BodyTube n EE arm beefier Poff Eective High Power stage Objective Adjustment stage Clips Cgg Diaphragm Finkenongdjustment Light Source Base 7  Microscope Part Function 1. Body Tube Connects the ________________ to the __________________ lenses. eyepiece objective Contains the _____________________ lenses. Can be rotated to change 2. Revolving Nosepiece obj magnification (_________________). 3. Low Power Objective Lens A second set of lenses. 4. Medium Power Objective Lens Each has a different ______________________________ power. 5. High Power Objective Lens magnification 6. Stage Clips Stage clips hold the ________________ in place. slides A rotating disk under the stage. It has different sized holes to 7. Diaphragm allow you to ________________ the amount of light on the specimen. regulate 8. Light Source Supplies the ________________ required to view the specimen. light 9. Eyepiece or Ocular Lens The lens that you __________ ________________. look through Supports the tube and connects it to the base. Used to 10. Arm __________________ the microscope when you carry it. support 11. Stage slides The flat platform where you place your ________________. Moves the stage up and down for ___________________________. 12. Coarse Adjustment Knob focusing **ONLY USE COARSE ADJUSTMENT WHEN ON THE owest ________________________ OBJECTIVE LENS** 13. Fine Adjustment Knob Moves the stage slightly to _____________________ the image. sharpen 14. Base The bottom of the microscope, used for ________________. support 8 Lesson 1.3: Developments in Imaging Technology and Staining Techniques There are three things that affect what we see in a microscope: ton resolvingPower 7 Magnification and Field of View colours shades Contrast: difference between ________________ or ________________. Light passes _____________________ cells in what is called brightfield microscopy. through When light passes through cells in a microscope, most of the cells seen are colorless. contrast Scientists quickly realized that manipulating the light source alters the ________________ between structures in the cell resulting in an improved image. Contrast Enhancing Techniques o Adding a ____________ or _____________________ agent. stain colouring Different stains adhere to different parts of a cell. Advantage: can be used to highlight specific ___________________ in a sample. structures Disadvantage: staining __________ the cells (cannot view _____________ tissue). kills o Changing the contrast by using a darker or lighter ________________________________. background Resolving Power Resolution (_____________________ ______________) The ability to ________________________ between two parts of an image. distinguish Regardless of the level of magnification, the clarity of an image depends on the _____________________ _____________ of the microscope. resoly powerallows you to see greater _____________. g o ____________ resolution detail pixels o The individual dots or squares of colour we see are called ________________. Fewer pixels means ________________ lower resolution. More pixels in the ____________ same ____________ area will result in higher resolution. on Theimage.ismuch 9 T.IEition Magnification and Field of View Magnification ________________________________: o When looking into a compound microscope, you are looking through two lenses: the lens in the ____________________ ece (________________ lens) and the __________________ lens object o In our school microscopes, the magnification of the lens in the eyepiece is ________. o The school microscopes have three different objective lenses. low power = ________ ax medium power = ________ 10 40 high power = ________ o To calculate the overall magnification of a microscope, ________________________ the ocular magnification by the objective magnification. multiply =( ) ( ) field View of _____________: _____________ _____ o The field of view (____________) F o V is the area that can be seen when looking through the lens of a microscope. Example 1 The following images have been taken using our school microscopes. a. Calculate the total magnification of the microscope for each objective lens. Power of Ocular Lens: 10x Low Power Medium Power High Power 4x 10x 40x objective and Ocular objective and Ocular and Ocular objective 10 4 10 0 40 100 400 b. What happens to the field of view as you increase the magnification? As you increase the magnification, the field of view decreases (gets smaller) 10  Calculating the F.O.V. Data Book = Ola Mags To Mag a Example 2 It doesn’t matter which is A and which is B, but once you write it down, stick to it. If for a particular microscope, the low power magnification is 4x, the high-power magnification LOW is 10x and the low-power field view is 4.5mm. What is the high-power field of view? 3 Loop OVA Magis Mag 4 HighMag Ox FOVB Maga High LOB FOV 4 5mm High For S 495hm 0.4 4 sn 4.5mm Example 3 IOVA 8 mm If for a particular microscope, the low power magnification is 4x, the low-power field view is ow 5.3 mm and the high-power field of view is 0.53 mm. What is the high-power magnification? OVA MagB mag 4 1080 158 For 5.3mm FOVB Maga high high for 0.53mm 3hn hIgn highpower mag Maga Maga Maga 0 0.1 E0.1 11 Maga 40  I Calculating the actual size of an object: = 550 FOV # FIT Data Book Example 4 2 sigdigs You are looking at an object under a microscope. Your field of view is measured to be 1.6 m. You estimate that you could fit the object 6 times in your field of view. What is the actual size of the object? FOV FOV 6mm 500 FIT IT 6 500 um 500 0 26666 µm 0.27 am Example 5 You are looking at the object pictured below under a microscope. Your field of view is measured to be 4.5 mm. What is the actual size of the object? The diameter of a sketch will notalways Ruler be the same as the field of view 4.4cm i For is 4.5mm Need to find the FIT 2 500 For Soo is so we look at the FIT enlargedsketch 500 4 5mm All the way across 4 4am 4.88 one single cell 0.9cm 12 500 0.92 04 mm 4 888 cells across 0.92mm Confocal Technology and Electron Microscopes Confocal Microscope (1980’s to present day) In a ______________________ microscope, a ____________ is used to focus light onto a specimen. confocal aser The reflection passes through a tiny opening (called a confocal ________________) to an electronic detector that turns the light into an image. pinhole The result is a high-________________________ picture of a thin section of the object. resolution It combines multiple sections together to create a ________ image. 3D Electron Microscopes (1930’s to present) ________________________ microscopes work similar to light microscopes, but they use a Electron beam of electrons to view an object instead of a beam of light. o Electrons are produced at the top of the microscope by an electron gun. A high voltage current is applied to a ________________ to excite electrons, cathode forming a continuous stream of electrons held within a ________________. m o The lenses used in the electron microscope are ___________________ __________. magnetic Scientist in Germany invented the first electron microscope in 1932, but Canadians refined ___________________ it. o Ernst Ruska (Germany) o Albert Prebus and James Hillier (Canada) There are two types of electron microscopes: Transition Electron Microscope TEM Scanning Electron Microscope SEM 13  Thin slices The Transition Electron Microscope (TEM) thin Focuses a beam of electrons at a very _____________ slice of the object. Advantages: o We can see tiny objects compared to a light microscope. Some TEM’s can magnify up to ________________________. 1000000 More than 100x the detail of a light microscope. Disadvantages: o the specimen must be cut into very thin slices. o The specimen must be ________________________ or ________________________. non biological o Difficult to get a 3D picture. non living Expensive o _____________________. Scanning Electron Microscope (SEM) A beam of electrons is passed over the specimen being observed to produce a 3-D image. Advantage: o The organism can be _____________________. living theoretically o Can magnify up to 300 000x. o Able to see ________________________ components of the cell never before seen. Disadvantage: structural Expensive o _____________________. 14 Lesson 1.4: Cell Research at the Molecular Level Cell Research at the Molecular Level Gene Mapping position A technique used to locate the _____________________ of specific genes within the genetics of an organism. Scientists used microscopes to view ____________________________________. chromosomes o Chromosomes are condensed DNA you can see under a microscope. o In 2001 scientists collaborated globally to map out human chromosomes. Project tumanmfff.gg o Lead to gene _____________________ of many different species (crops, other animals, etc.) Fuorescence Micros _____________________________ _____________________ P Green Fluorescent Protein (______) was first found in luminescent _______________________. GFP can be attached to certain parts of a cell. jellyfish ultraviolet o The protein glows a bright green when exposed to __________________________ light. o Allows scientists to study specific cell activity. GFP technology is being used to study ____________________________________ diseases such as degenerative Alzheimer’s and Parkinson’s which will hopefully lead to treatment breakthroughs. Although current microscopes can magnify specimens up to 10 000 000x, they still cannot discern the _____________________ details of individual molecules. subatomic Atoms are really small, smaller than the _____________________ of an electron. wavelength It is impossible to see one with the naked eye, even with the most powerful of microscopes. X-Ray ___________________________________ Crystallography X-rays have a wavelength short enough that they can be used to "_________" atoms. see X-ray crystallography studies the structure of molecules by means of x-rays and specials sensors that analyze patterns of x-ray _____________________. scattering o The structure of ________ was originally discovered using X-ray crystallography. DNA o X-rays scattered off atoms in crystallized arrays of DNA to form a complex pattern of dots on _________________________________ film. photograd o This technique was to identify the ______________ _____________ shape of DNA. qjh o Crystallographic analysis of DNA showed a _______________ every 3.4 × 10 mm. 15