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Unit One: Cell Biology. National 4/5. Units: Complete Life on Earth – mid Sept Cell Biology – Sept - Dec Multicellular Animals – Jan - April. How is the course assessed?. Course work: 3 end of unit tests (one for each unit) – can have resits if necessary One Practical investigation
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National 4/5 Units: • Complete Life on Earth – mid Sept • Cell Biology – Sept - Dec • Multicellular Animals – Jan - April National 4/5 Biology Course Unit 1
How is the course assessed? • Course work: • 3 end of unit tests (one for each unit) – can have resits if necessary • One Practical investigation • One mini research project (100 words) • One LARGE research project (Added Value) (500-800 words) • NATIONAL 5 – Final exam! National 4/5 Biology Course Unit 1
Work Classwork to be done in jotter. Remember it every day! You will get set homework sometimes – but expected to learn the work done each day as you go along!!! National 4/5 Biology Course Unit 1
What is in Unit One? • Cell Biology: • Cell Structure • Transport across membranes • Producing new cells • DNA and protein production • Genetic engineering • Proteins and enzymes • Aerobic respiration • Photosynthesis National 4/5 Biology Course Unit 1
Cell structure LI: 1. Identify and name the structures found in an animal cell. 2. State the function of the structures in an animal cell. 3. Identify and name the structures found in an plant cell. 2. State the function of the structures in an plant cell. National 4/5 Biology Course Unit 1
Cell Structure Cells are the building blocks of all life. Cells video National 4/5 Biology Course Unit 1
Cell Structure National 4/5 Biology Course Unit 1 We will be looking at 4 different cell types:- • Animal cells • Plant cells • Bacterial cells, and • Fungal cells. You have already looked at the basic structure of animal and plant cells in S1- S3. We will be looking at all of these cells in greater detail.
What can you remember from last year? Task One: Complete the revision worksheet on cells. National 4/5 Biology Course Unit 1
Cell Structure National 4/5 Biology Course Unit 1 Task 2: Prepare slides for examination under a light microscope. Using the help sheets provided prepare one type of slide – cheek cell, onion cell or Elodea pondweed. After you have examined your own slide share your slide with a group that has prepared a different slide . You should look at all 3 cell types.
Cheek Cells National 4/5 Biology Course Unit 1 These are cheek cells viewed at 100x magnification using a light microscope. http://www.stancoe.org/patterson/cms/staff/humancheekcellwebpage.htm
Onion Skin Cells These are onion skin cells viewed at 40x magnification using a light microscope. National 4/5 Biology Course Unit 1 http://www.baileybio.com/plogger/images/biology/lab_-_plant___animal_cells/onion_cells.jpg
Elodea Pondweed Cells These are Elodea pondweed cells viewed at 100x magnification using a light microscope National 4/5 Biology Course Unit 1 http://seys-science.wikispaces.com/elodea+g
Cell Structure Image from Wikipedia commons http://en.wikipedia.org/wiki/File:Electron_Microscope.jpg National 4/5 Biology Course Unit 1 We will now look in more detail at the structure of animal and plant cells. To see more detail or the ultra structure of cells we need to use and electron microscope.
Cell Structure - Organelles National 4/5 Biology Course Unit 1 Organelle is the name given to the structures found inside the cell e.g. Nucleus, vacuole, chloroplasts etc. You need to know about 2 more organelles. Mitochondria and Ribosomes
Mitochondria Mitochondria are found in the cytoplasm of the cell. National 4/5 Biology Course Unit 1 Mitochondria are the power houses of cells. They convert energy into forms that are usable by the cell. They are found in the cytoplasm and are the sites of cellular respiration which generates fuel for the cell's activities.
National 4/5 Biology Course Unit 1 Electron microscope image of a mitochondrion (credit: Tom Deerinck and Jeff Martell/MIT) http://people.eku.edu/ritchisong/ritchiso/mitochondrion2.gif
Ribosomes National 4/5 Biology Course Unit 1 Ribosomes can be found floating free in the cytoplasm or attached to another type of organelle called Rough Endoplasmic Reticulum or R.E.R. for short. (you don’t have to know about R.E.R!)
Ribosomes are responsible for protein synthesis, i.e. this is where amino acids are assembled into proteins. Electron Microscope image of ribosomes. http://www.cbv.ns.ca/bec/science/cell/page11a.gif http://bioweb.uwlax.edu/genweb/molecular/theory/translation/ribosome.jpg National 4/5 Biology Course Unit 1
Cell Structure – Organelles National 4/5 Biology Course Unit 1 Task 3 – Collect the diagram sheets of the animal cell and the plant cell. Label any structures you recognise. You will need to include:- Cell membrane, nucleus, cell wall, vacuole, chloroplast, cytoplasm, ribosome and mitochondria.
Animal Cell Diagram Cytoplasm Nucleus Ribosomes Mitochondrion Cell Membrane National 4/5 Biology Course Unit 1
Plant Cell Diagram Ribosomes Mitochondria Cell Membrane Cytoplasm Cell Wall Nucleus Chloroplast Vacuole National 4/5 Biology Course Unit 1
Cell Structure - Organelles National 4/5 Biology Course Unit 1 Task 4 – Collect and complete the worksheet :– Cell structures and functions.
Bacteria and fungi LI: 1. Identify and name the structures found in a bacterial cell. 2. State the function of the structures in a bacterial cell. 3. Identify and name the structures found in a fungal cell. 4. State the function of the structures in a fungal cell. National 4/5 Biology Course Unit 1
Bacterial Cells National 4/5 Biology Course Unit 1 “For the first half of geological time our ancestors were bacteria. Most creatures still are bacteria, and each one of our trillions of cells is a colony of bacteria.” Richard Dawkins
Bacteria http://en.wikipedia.org/wiki/File:Gram_Stain_Anthrax.jpg National 4/5 Biology Course Unit 1 TThey are the oldest living organisms on earth. They are everywhere. We find them on and in the human body, in the air we breathe, on the surfaces we touch, in the food we eat. Almost 99% of these bacteria are helpful, whereas the remaining are the notorious ones.Some are essential for proper growth of other living beings. They are either free-living or form a symbiotic relationship with animals or plants.
Structure of Bacteria National 4/5 Biology Course Unit 1 Bacteria can occur in different shapes. However their basic structure is the same. Task: Collect the bacterial cell diagram handout and the information sheet. Use the information to complete the labels on the diagram and to complete the table.
Cytoplasm Cell Wall Capsule Plasmid Genetic material Cell Membrane National 4/5 Biology Course Unit 1
Provides additional protection from the environment It strengthens and supports the cell Controls the movement of substances into and out of the cell Made of DNA and controls the activities of the cell Circular genetic material. Can convey special abilities, e.g. a resistance to certain antibiotics. They can be manipulated by man to produce bacterial cells that produce useful products e.g. Insulin, hormones and enzymes. Most chemical processes take place here controlled by enzymes National 4/5 Biology Course Unit 1
Structure of a fungal cell National 4/5 Biology Course Unit 1 Task: Collect the diagram sheet and label any of the structures and organelles you recognise.
Structure of a fungal cell Nucleus Cell Wall Cytoplasm Vacuole Cell Membrane National 4/5 Biology Course Unit 1
The fungal cell wall. Just as the bacterial cell wall has a different chemical structure from a plant cell wall, so does the fungal cell wall. The fungal cell wall is made from a chemical called chitin. National 4/5 Biology Course Unit 1 All the cell parts are now familiar. You should be able to compare all the cell types and identify which parts are similar and which are not. While all the cell parts have the same functions as before there is one difference.
It is important that you know National 4/5 Biology Course Unit 1 The cell walls in plant, bacterial and fungal cells is structurally and chemically different.
Measuring cell size LI: 1. Be able to calculate the length and breadth of cell seen through a microscope. National 4/5 Biology Course Unit 1
Just how tiny are cells? “How big?” This link will show you how tiny cells are. Cells can be seen more clearly using a microscope. National 4/5 Biology Course Unit 1
Magnification Eyepiece Lens Total magnification is worked out by multiplying the eyepiece lens magnification by the objective lens magnification. Objective Lens National 4/5 Biology Course Unit 1
Copy and complete this table National 4/5 Biology Course Unit 1
Working out the size of a cell Field of view = 2 mm The field of view is the area you can see down the microscope. Field of view Length = of each cell (mm) Number of cells e.g. 2 ÷ 5 = 0.4 mm So each cell measures 0.4 mm. National 4/5 Biology Course Unit 1
Field of view = 2 mm Collect a version of this diagram. Your teacher will tell you how many cells to draw in the circle. Calculate the length of your cell in millimetres (mm). Swap with other and calculate the length of their cells. National 4/5 Biology Course Unit 1
The cell membrane LI: 1. Describe the composition of the cell membrane 2. Describe how the structure of the membrane relates to its permeability. 3. Define the term “passive transport” National 4/5 Biology Course Unit 1
The Cell Membrane • The cell membrane (or plasma membrane) is made up of a bilayer of lipids with protein scattered throughout and is selectively permeable. • Proteins can; • be attached to the surface • be embedded within the bilayer • span the whole bilayer • form channels in the lipid bilayer National 4/5 Biology Course Unit 1
National 4/5 Biology Course Unit 1 Small molecules can pass through pores in the membrane made by channel forming proteins and enter or leave the cell. This is why the plasma membrane is selectively permeable. This transport of molecules is passive and requires no energy as it is with the concentration gradient.
Diffusion LI: 1. Define the term “diffusion” 2. Explain how the process of diffusion occurs across a selectively permeable membrane. National 4/5 Biology Course Unit 1
Diffusion Diffusion is the name given to this movement of the molecules of a substance from a region of high concentration of that substance to a region of low concentration of that substance until the concentration becomes equal. National 4/5 Biology Course Unit 1
Diffusion Activity Cut a 20cm piece of visking tubing and tie a knot in one end. Soak the tubing in water and never let it dry out during the experiment. Fill the visking tubing with 5-10cm3 starch and glucose solution and seal with another knot. Place this in a boiling tube of water completely submerged and leave until the next lesson. National 4/5 Biology Course Unit 1
Test for starch 2. Add 4 drops of IODINE 1. Put sample on tray 2. Add 4 drops of BENEDICTSSOLUTION Test for sugar BOILING WATER 3. If sugar is present it goes from blue to orange 1. Put sample in test tube – IN a beaker of BOILING WATER Take a small sample of the water from around the test tube. Test for starch and sugar 3. If starch is present it goes from brown to black National 4/5 Biology Course Unit 1
Activity Perform Benedict’s test and starch test on the water in the boiling tube from Diffusion in a Model Cell experiment you set up last lesson. Explain your results in terms of diffusion. (LO1 assessment). National 4/5 Biology Course Unit 1