SNC 1DO LESSON PLANS

Ontario Curriculum objectives: U=understanding concepts (U1-U10) D=developing skills  (D1-D10) R=relating science (R1-R4)

Text: Sciencepower 9, McGraw-Hill

BIOLOGY -the study of life

Microscopes: tools used in the study of biology to view samples
Magnifying glass: 1 glass magnifying lens
Compound Light Microscope: 2 glass magnifying lenses with one eyepiece (2-D vision)
Stereo Dissecting Microscope: 3 glass magnifying lenses with two eyepieces (3-D vision)

Describe microscope parts and care of compound light microscope (carry with two hands,etc)

Magnification: making an object appear larger
Resolution: ability to distinguish between two objects

Total Magnification Formula is how many times larger an object appears under a microscope
          Total Magnification Formula = Ocular Lens Magnifacation X Objective Lens Magnification
          There is one ocular lens and three possible objective lenses (low, medium, high) on our microscopes

Field width is the diameter of the area you can view through a microscope
          Field width on low power = find using a ruler (4 mm on our microscopes)
          Field width on medium power = (low power mag./med. power mag.) X low power field width
          Field of width on high power = (low power mag./high power mag.) X low power field width

Actual size of object = (Field width using certain objective lens)/(the number of objects needed to fill field width)
          e.g. If the field width is 0.8 mm and a cell is half the size of the field width, find the size of the cell.
                 size of cell = field width/number of objects to fill field width = 0.8 mm/2 = 0.4 mm

Life - certain characteristics should be present in an organism for it to be considered living

1. Metabolism: chemical reactions that store or release energy
        Anabolism: chemical reactions that store energy (e.g. protein synthesis)
        Catabolism: chemical reactions that release energy (e.g. breakdown of sugar)

2. Reproduction: making copies of same type of organism
        Asexual: one cell makes two cells with identical genetic material
        Sexual: two cells make one cell

3. Movement under own power: 

4. Alter the environment: produce wastes, produce heat, use up oxygen

5. Growth: cells increase in size

6. Respond to stimulus (environmental change):
        Receptor cells detect stimulus, nerves carry message to brain, nerves carry message from
        brain to effector cells which respond (muscles and glands)

*metabolism and reproduction are the most important of these characteristics (and
 the only ones possessed by a virus)

School rules for drawing a proper biological scientific diagrams:
    -1 cm border around outside left clear
    -title underlined over diagram
    -use pencil for drawing on a blank paper, no colour in diagram
    -your name and date in top right corner (not in border)
    -labels printed on right, label lines are parallel and do not cross
    -diagram uses solid lines and has stipple for shading
    -under diagram place magnification, size of object and description (e.g. colour)

Use class time to draw a scientific diagram of an euglena

Cell Membrane - surrounds cell, lets material in and out of cell
Cell Wall - only in plants, protective outer layer

Cytoplasm - material inside cell, outside nucleus (mostly water)
Nucleoplasm - material inside nucleus (mostly water)
Protoplasm - cytoplasm and nucleoplasm

Mitochondria - cell part that produces useful energy for the cell
Chloroplast - only in plants, green, makes sugar by photosynthesis

Nuclear Membrane - lets material in and out of nucleus
DNA - genetic material in nucleus...material which determines how a cell will look and act
Nucleus - control center for cell

Centrioles - outside nucleus, only in animal cells, involved in cell division

Vacuoles - one large in plants, many small in animals, storage

Draw and label one plant cell and one animal cell on prepared slided

Plant cells contain cell walls, chloroplasts and usually have on large vacuole
Animal cells contain centrioles and usually have many small vacuoles

Prepare a wet mount of an onion cell with stain by adding a drop of water/stain to sample, then adding coverslip

Draw and label one onion cell on your slide

-all living things are made of cells and cell products

-cells are the basic structural (building blocks) and functional (working) parts of organisms

-cells come from other cells

-nucleus determines the appearance of algae  -the nucleus must contains genetic material (see investigation 1-B)

-Griffith and Avery (Canadian) showed that DNA in the nucleus was genetic material
            eg. mouse with lethal bacteria = dead mouse full of live lethal bacteria
                  mouse with non-lethal bacteria = live mouse
                  mouse with dead lethal bacteria = live mouse
                  mouse with both dead lethal bacteria and live non-lethal bacteria = dead mouse full of live lethal bacteria
                 -a chemical called DNA was transferred from dead bacteria (carrying lethal trait) to live bacteria

-DNA (deoxyribonucleic acid) carries traits and is found in nucleus of cells

FUNCTIONS OF DNA
-makes proteins (which provide you with your appearance and traits)
-makes DNA (can be passed on from generation to generation)
DNA makes you appear as you do, and is inherited

MUTATION: innaccurate copying of DNA (change in DNA)

-mitosis is the process of one cell making two cells which contain DNA identical to the parent cell

CENTRIOLES -pairs of cytoskeleteton organelles, only in animal cells, aid in animal cell division
SPINDLE FIBRES -threads of cytoskeleton, involved in cell division by pulling DNA
CHROMATIN -pile of DNA normally found in the nucleus of a cell
CHROMOSOMES -single strand or joined pair of strands of DNA acting as a unit
CHROMATID -single strand of chromosome made of  two strands of DNA (it is called a chromosome when on its own)
CENTROMERE -protein holds chromatids together in a two stranded chromosome

WHY CARRY OUT MITOSIS?
fertilized egg = 1 large cell  called a zygote formed when an egg and sperm join
-mitosis is needed for this cell to GROW

STAGES OF GROWTH IN HUMANS BEFORE BIRTH:
zygote--->embryo (3 months)    --->fetus (7 months)
                -developing stage         -growing stage
                -body parts form            -parts get bigger

also, mitosis REPLACES dead cells
                     REPAIRS damaged cells

In humans, mitosis occurs in all cells except sperm and egg, but stops in nerve and muscle cells after birth
-only a limited number of cell divisions may occur in human cells
-uncontrolled Mitosis = CANCER and can occur in any body tissue.

In single celled organisms, mitosis is used for reproduction only
    eg. bacteria, yeast, algae have unlimited number of cell divisions

INTERPHASE    G1 phase -growth (4 hours long)
                         S phase - DNA doubles (chromosomes go from single to double strands) and growth (10 hours long)
                         G2 phase -growth (4 hours long)
                         centrioles double in animal cells during interphase

MITOSIS (PMAT) (2 hours long)
1-PROPHASE       -DNA thickens (chromatin forms chromosomes)
                            -nuclear membrane disappears
                            -spindle fibres start to form
2-METAPHASE     -centrioles move to "poles" (opposite ends of the cell)
                            -chromosomes line up on the "equator" (center of cell)
                            -spindle fibres join chromosomes to centrioles (at poles)
3-ANAPHASE       -chromosomes separate into chromatids (now called chromosomes)
                            -spindle fibres pull chromosomes towards poles
4-TELOPHASE      -nuclear membrane / chromatin reforms

                            CYTOKINESIS -cell membrane pinches in to split the cell

Time spent to make a new cell (one cell makes two cells) is 20 hours total
                -the first 100 cell divisions a zygote undergoes just produces smaller and smaller identical cells
                -this ball of 100 smaller cellls (same overall size as zygote) is called a blastula
                -the 100 cell blastula will now implant into the uterus of a female and start to grow larger

How long will it take to change from a single celled zygote into an implanted blastula?
                1 - 2 - 4 - 8 - 16 - 32 - 64 - 128 cells big made after 7 divisions (formula 2ⁿ where n = number of divisions)
                7 divisions X 20 hours per division = 140 hours/24 hours a day = 5.8 days for blastula to implant

PLANTS: contain no centrioles

CYTOKENISIS:   animal cells have no cell wall, so the cell membrane pinches in to form cleavage furrow
                          plant cells have outer wall, so the cell wall forms cell plate between two cells

-Use pipecleaners as models of chromosomes to illustrate the behaviour of a cell during mitosis
-learn names of relevent cell parts and be able to describe stages of mitosis using these models

-view and discuss secret of life video and questions

ASEXUAL REPRODUCTION -1 parent cell makes 2 daughter cells with the same chromomes as the parent

TYPES OF ASEXUAL REPRODUCTION:
BINARY FISSION -1 cell makes two cells of same size (eg. amoeba, bacteria)
BUDDING -1 cell makes two cells of different size (eg. yeast)
VEGITATIVE PROPAGATION -part of plant grows (leaf, stem) into a new plant (eg. spider plant)

other types...    REPAIR -multicellular organisms grow scar tissue to close wound
                        REGENERATION -missing limb regrows eg. salamander arm
                        SPORE FORMATION -single cell in a "shell", formed in poor conditions, and open in
                                                                   good  conditions  eg. bacteria or fungi

Terms for comparison:
SEXUAL REPRODUCTION -the production of new organisms by fertilization
FERTILIZATION -egg and sperm (half DNA...haploid) join to make a zygote (full DNA...diploid)
                         -Most body cells are diploid, and these are now able to reproduce by MITOSIS to make more diploid cells
MUTATION -random altering of DNA (caused by UV light, smoking, radiation,...)

ASEXUAL REPRODUCTION  -exact copies of all traits passed on
                                            advantage -all good traits are passed on
                                            -variations arise through mutations
SEXUAL REPRODUCTION    -variety of traits produced
                                            advantage -variety improves chance of surviving an environmental change
                                            -variations arise from mutations, fertilization and meiosi

Terms for sexual reproduction: 
MEIOSIS -production of gametes (also called sex cells = sperm in male, egg in female)
               -a parent cell with two sets of DNA (diploid) splits twice producing 4 daughter cells with half parents DNA (haploid)
               -DNA splits randomly during this process, producing a wide variety of gametes

HERMAPHRODITE: organism able to make both gametes (egg and sperm)
                               -advantages...mate is not needed
                                                     or they can mate with any of the same type of organism
                                                     eg. flowers and earthworms
INTERNAL FERTILIZATION: egg is fertilized inside of mother
                                    -advantages...egg is protected
                                                          less eggs are needed as fertilization is usually successful
                                                          eg. humans, chickens
EXTERNAL FERTILIZATION: egg is fertilized outsid of mother, occurs in the water
                                    -more eggs are needed as less protection is provided
                                                         eg. fish, frogs

IN VITRO FERTILIZATION (IVF)
TIMELINE
24 hours    ----------------->         6 days - 9 weeks            ------------------------>16 weeks
-egg is fertilized                    -embryo develops                                    -fetus grows
 (zygote)                                 (mitosis occurs)                                        (mitosis occurs)
-done in lab for in vitro         -zygote implants in uterus at 6 days
                                             -egg is put back in mother in IVF
                                             -ultrasound, amniocentesis, chorionic villi
                                              sampling are done to embryo

ULTRASOUND -sound picture showing appearance of baby...it is done to find the babies sex, abnormal growth, location

AMNIOCENTISIS      -fluid is removed (10 mL) from amniotic sac via needle)
                                -some baby cells are in fluid
                                -these cells are grown on food
                                -take a picture of some cells during mitosis (chromosomes are visible)
                                -this picture is called a KARYOTYPE
                                -normally you should see 23 pairs of chromosomes in a human (46 total)
                                -too many/few chromosomes could result in damage to baby
                                 ALSO: females have 2 X chromosomes, males have 1 X and 1 Y chromosome

-build and demonstrate a genetics activity as a team

-begin the genetic disease research project in the library

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