Midterm Review Microscope Diagram

 Characteristics of Life(DR GECHEE!!!)  

All living things:

1. Are made of cells

   1. -Uni-cellular means “single celled”   

(example: yeast or paramecium)

2. -Multi-cellular means “many celled”             

 (example: Plants and animals)

2. Reproduce

   1. Sexual: 

      1. two cells from different parents join 

      2. half from “Mom” and half from “Dad”

   2. Asexual:

      1. Genetically identical to one parent

3. are based on a universal genetic code

   1. DNA determines inherited traits.

4. grow and develop

   1. Living things exhibit a life cycle which means that they grow and change during the organism’s lifespan.

5. obtain and use energy

   1. Energy is used to perform chemical reactions which organisms use to build up or break down materials.

   2. This process is known as metabolism. 

   3. The sun is the ultimate source of all energy for most organisms.

6. respond to their environment

   1. Plants turn toward the sun.

7. maintain a stable internal environment

   1. The process by which organisms keep their internal conditions stable is homeostasis. You sweat when you are hot, and shiver when you are cold.

8. evolve or change over time

   1. Evolution is the gradual adaptation process of organisms and species throughout time.

History of Cells

• 1665-  Robert Hooke- use of a light microscope to look at thin slices of cork, named the structures cells after the rooms in a monastery

• 1838- Matthias Schleiden- all plants are made of cells

• 1839 – Theodore Schwann- all animals are made of cells

• 1853- Rudolph Virchow – all cells come from existing cells

Levels of Organization 

• Bob’s = Biosphere

  • The whole world, including all biotic and abiotic factor, wind, climate, temperature plants and animals 

• Extraordinary =  Ecosystem

  •  All biotic and abiotic thing in a particular area 

• Cat =  Community 

  • All organism living in a specific area 

• Pounced = Population 

  • One group of an organisms 

• On = Organism 

  • One individual make up of organs with makes the organ system which make the organisms

• The =  Tissues 

  • Which make up organs which make up organ systems 

• Crazy = cells

• Mouse =  Molecules 

Scientific method

1. Define the Problem

2. Background Research 

3. Form a Hypothesis

4. Design a controlled Experiment

5. Observe, Record and Analyze Data (ORA)

6. Draw Conclusions

7. Communicate Results

8. Theory or A NEW PROBLEM!!!

Basic Cell Structure

1. Cell membrane

   1. thin flexible barrier that  contains the cytoplasm.

2. Cell wall 

   1.  strong layer outside of the cell membrane used for support and structure.

3. Nucleus

   1.  contains genetic material and  controls cell activities.

4. Cytoplasm

   1. material inside the cell membrane that does not include the nucleus. 

5. Cell Wall(plants only)

   1. Provide support and protection for the cell

   2. Made of carbohydrates and protein

   3. Plant cell walls made up of Cellulose

6. Nucleus

   1. Controls most cell processes

   2. Contains hereditary information of the cell (DNA- Deoxy-ribonucleic acid)

   3. DNA combines with proteins to form chromatin

7. Nucleolus

   1.  small dense region in the nucleus where the assembly of ribosomes and protein formation begins

8. Nuclear Envelope

   1.  double membrane dotted with nuclear pores

9. Cytoskeleton

   1. Helps to support the cell wall.

   2. Microtubules 

      1. Hollow tubes of protein

      2. 25 nm in diameter

      3. Maintain cell shape

      4. Serve as “tracks” along which micro-organism move

      5. Helps in CELL DIVISION

   3. Microfilaments 

      1. Long thin fibers that function in movement and the support of the cell

      2. 7 nm in diameter

      3. Tough flexible framework that supports the cell

      4. Helps to move organelles (little organs) within the cell

   4. Network of proteins and filaments that help the cell to maintain its shape.

      1. Pore = Passages

      2. Cyto = cell

      3. Filament= threads

10. Ribosomes

    1. Make proteins

    2. Respond to coded messages

    3. Produced in the nucleus

11. Endoplasmic Reticulum “ER”

    1. Internal membrane system

    2. Organelle in which the components of the cell membrane are assembled

    3. Area where proteins are modified

       1. Rough ER- RER- synthesis of proteins, ribosomes stud the surface

       2. Smooth ER – SER- no ribosomes

12. Golgi Apparatus

    1. Enzymes attach Carbs and lipids to protein

    2. Send products to final destination

    3. Looks like stacks of pancakes

13. Lysosomes

    1. Enclose enzymes

    2. Break down lipids, carbohydrates and proteins into particles that can be used by the cell

    3. Break down organelles that have outlived their usefulness

14. Vacuoles

    1. Sac like structures that store salts, proteins and carbohydrates

    2. Help to support plant structures

15. Chloroplasts( plants only )

    1. Use energy from the sun to make energy rich molecules aka GLUCOSE

    2. The process is called photosynthesis

    3. Contain green pigments

16. Mitochondria 

    1. Powerhouse of the cell

    2. Use energy for growth development and movement

Cell Membrane 

1. Cell Membrane: made of a phospholipid bilayer

   1. Surrounds and regulates the passage of materials into and out of the cell

   2.  Phospholipid- double layer sheet

   3. Membrane lipids- 

      1.  Phosphate head and 2 lipid tails, 

      2.  Creates a bilayer

   4. Fluid Mosaic Model:

      1. Layer in membrane is fluid in motion and lipids and proteins can move within the bilayer

      2. The layer may contain carbohydrate chains and protein channels.

2. Diffusion:

   1. Molecules move from high concentration to low concentration.

      1. A. CONCENTRATION: # molecules of a solute in a given volume of solution (DENSITY)

   2. Molecules move randomly until they hit something

   3. EQUILIBRIUM: the concentration of the solute is the same throughout the solution

      1. Density = mass/volume

   4. Passive Diffusion

      1. Materials move across the cell membrane but no energy is required:

         1. The membrane is said to be permeable if it allows substances to cross

3. Osmosis

   1. Selectively permeable:

      1.  Some substances can pass through a membrane while others cannot.

   2. Osmosis allows water H2O to pass through selectively permeable membranes.

   3. Direction of osmosis depends on solute

   4. Concentration

4. 3 types of solutions

   1.  HypOtOnic: 

      1. solute decreased concentration of particles outside the cell and water moves into the cell

   2. Hypertonic:

      1.  solute increased concentration of particles outside the cell and water moves out of the cell

   3. ISOTONIC: 

      1. solute concentration is the same: water moves in and out of the cell

(WATER ALWAYS MOVES FROM AN AREA OF HIGH CONCENTRATION TO EQUILIBRIUM)

5.  Endocytosis

   1. Moves large molecules, fluids and other cells INTO the cell

   2. Portion of the cell makes a pouch that pinches off into the cytoplasm

      1. Pinocytosis: transport of small “bits” of liquid

      2. Phagocytosis- transport of large particles

6. Exocytosis

   1. Vesicles in the cytoplasm fuse with the cell membrane and release contents OUT OF the cell

   2. Proteins made by ribosomes may be expelled this way

pH 

1. The PH Scale

   1.  pH means “potential of hydrogen”.

   2. The pH scale indicates the concentration of hydrogen ions (H+) in a solution.

   3. Acids give off H+ ions.

   4. Bases give off OH- or hydroxide ions.

   5. When a substance is neutral it has a pH of 7, there is an EQUAL number of H+ and OH- ions

   6. The pH scale is numbered from 0-14

2. Acid 

   1. Substance that contains an increased number of H+ ions.

   2. Acids have a pH of 0-6.

   3. A pH of 1 is very acidic.

   4.  As pH approaches 7 it becomes more “weak”.

   5. Common household acids: lemon juice,  vinegar, tomatoes

3. Bases 

   1. Substances that contain more hydroxide ions

   2. (OH-) than hydrogen ions (H+).

   3. A pH of 14 is a very strong base. The closer to 7 on the pH scale the “weaker” the base.

   4. Common household bases: soaps, baking soda, cleaning solutions

4. Chemical Indicators

   1. pH paper

      1. Absorbent paper, usually in strip form, has a color changing dye. It is useful for estimating the approximate pH of a solution.

   2. Blue Litmus paper

      1. Will turn red in the presence of an acid and will stay blue in the presence of an abase.

   3. Red Litmus paper

      1. Will turn blue in the presence of a base and stay red in the presence of an acid.

CHEMISTRY OF LIFE

• THE NATURE OF MATTER

  • Atom: basic unit of matter

    • Nucleus: central core of the atom

      • Proton: positive electrical charge

      • Neutron: no electrical charge

  • Electrons

    •  Negative charge

    • Very little mass

    • Very high speed around nucleus

    •  # of electrons = # of protons

  • Element: a pure substance that consists of one type of atom

    • Approx. 30 elements are required for life

    • Represented by 1 or 2 letter symbols

      • C = carbon, Na = sodium

    • Atomic number: the number of protons in an atom

      •  Carbon = 6: 6 protons and 6 electron

• Isotopes

  • atoms of the same element that differ in the number of neutrons they contain

    • Mass number changes

    •  Radioactive isotopes: nuclei break down over time

    • Used in cancer treatment, killing bacteria, and can determine the age of rocks and fossils

• PERIODIC TABLE

  • Compounds

    • substance that is made of atoms of two or more elements

      • H2O = 2:1 ratio of H to O

    •  Elements undergo chemical reactions as a result of unfilled energy levels

  • Covalent bonds

    • forms when two atoms share one or more electrons

      • ex. H2O

  • Molecule

    • the smallest unit of a covalently-bonded compound

  • Ionic Bonds

    •  transfer of one or more electrons from one atom to another

      • Lose electrons = positively charged ion

      • Gain electrons = negatively charged ion

        • Opposite charges attract!

        • ex. NaCl (salt)

  • Van der Waals forces

    • hold large molecules together

      • attraction develops between oppositely

      • charged regions of nearby molecules

• 2-3 CARBON COMPOUNDS

  • Carbon Chemistry

    • Carbon has 4 electrons in its outermost shell at all times.

    •  Carbon bonds with itself to form long chains of molecules

    • Carbon can form single, double, triple bonds with itself and other molecules and can form rings

  • Macromolecule

    • “giant molecules”

    • Small monomers combine to form large polymers through polymerization

    • Four groups of macromolecules include:

      • Carbohydrates

        •  Made up of carbon, hydrogen, and oxygen in a 1:2:1 ratio

        • Used by living things for energy and structure

        • Monosaccharides: single sugars

          • Glucose = blood sugar

          •  galactose = milk sugar

          • fructose = fruit sugar

        • Polysaccharides: large sugars

          • Glycogen = excess sugar stored in animal muscle cells

          • Starch = excess sugar in plants

          • Cellulose = tough fibers for strength in plants

      • Proteins

        •  Contain oxygen, hydrogen, carbon, and nitrogen

        • Many amino acids make a protein

          • amino group (-NH2) and carboxyl group (COOH)

        •  20 amino acids exist

          • all alike except for R group

          •  R group gives the protein its characteristics like reaction rates, cell processes, form bones and muscles, fight disease 

•  Nucleic acids

  •   Contain hydrogen, oxygen, nitrogen, carbon, and phosphorus

  • Store and transmit genetic information

  •  RNA and DNA

  •   Made up of nucleotides

    •   5-carbon sugar

    • phosphate group

    • nitrogenous base

• Lipids

  • Made up of carbon, hydrogen and oxygen

  •  Include fats, oils, steroids, and waxes

  • Store energy and make biological membranes and waterproof coverings 

  • Glycerol + fatty acid = lipid

  • Saturated:  all carbon atoms in the chain is joined to another carbon by a single bond

    • solid at room temp (butter, lard)

  • Unsaturated:  if there is one double bond between carbons

    • liquid at room temp (olive oil)

• 2-4 CHEMICAL REACTIONS AND ENZYMES

  • Chemical Reactions:  break bonds in reactants and create new bonds in the products

    • Reactants enter into the reaction

    • Products are made by the reaction

  • Energy Changes

    • Reactions that release energy occur spontaneously

    • An energy source is needed for any reaction that absorbs energy

    •  Plants and animals both store and release energy to stay alive

  • Activation energy:  energy needed to start a reaction

    • Enzymes:  speed up the rate of reaction for specific chemical reactions

  • Enzyme-Substrate Complex

    • Substrates:  reactants

    • Enzymes provide a place “ACTIVE SITE”for the reactants to come together and react, using less activation energy

    •  The enzyme and substrate fit together like a lock and key

    • When the products are released, the enzyme can begin again  

    • They work to regulate chemical pathways, make materials that cells need, release energy, and transfer information

      • PROBLEM:  they need certain pH values and temperatures to work

THE 8 CHARACTERISTICS OF ENZYMES

1. fit together like a lock and key

2. optimal pH

3. optimal temperature

4. specific

5. recycled

6. biological catalyst

7. Increase rate of reaction by lowering activation energy

8. most enzymes end in ase

Organic Compound Indicators 

CELL GROWTH AND DIVISION

• Cell Division

  • Cell division is the process by which a cell divides into two daughter cells.

  • Before the cell divides it copies or replicates all its DNA.

  • Cell division solves the problem by increasing the ratio of surface area to volume.

• Chromosomes

  • Contain the genetic material of the cell

  • Made of DNA – Deoxyribonucleic acid

  • Are not visible except during cell division

• The Cell Cycle

  • INTERPHASE - The longest phase in which a cell performs normal cell functions.

    • G1 – cell growth

    • S – DNA synthesis

    • G2 – preparation for mitosis

  • MITOSIS “Cell Division” – M Phase

    • Prophase

      • The 1st and longest phase of cell division.

      • Uses 60% of the time in the mitotic phase

      • Chromosomes are formed.

      • Nuclear membrane dissolves and the nucleolus disappears.

      • Centrioles replicate and move to opposite poles of the cell

      • The spindle, a fanlike microtubule structure appears.

    • Metaphase

      • This is the second phase of mitosis.

      • Chromosomes line up on the equatorial center of the cell.

      • Each chromosome is attached to a spindle fiber at the centromere.

    • Anaphase

      • This is the third phase of mitosis

      • Spindle fibers contract towards the poles causing the chromosomes to pull apart.

      • Chromosomes move to opposite ends of the cells

      • Anaphase ends when the chromosomes stop moving.

    • Telophase

      • The nuclear membrane and nucleolus reappear.

      • The cell membrane begins to pinch together. This process is called cell cleavage.

      • Chromosomes begin to unravel and return to their original form of chromatin.

(MITOSIS IS COMPLETE)

• Cytokinesis

  • 2 new DAUGHTER CELLS are produced by the cell membrane pinching the cytoplasm into 2 equal parts.

  • Each cell is independent of the other.

  • Each cell is genetically identical and contains a full complement of genetic material (Diploid).

MEIOSIS

DNA 

• Genes in our DNA contain instructions that tell cells which proteins to make and when to make them.

• Structure of DNA

  • Each DNA molecule contains two long chains of repeating subunits called nucleotides.

• Nucleotide

  • Nitrogenous base

  • Phosphate group

  • Deoxyribose sugar

• Double Helix

  • The structure of the Double Helix was discovered by Watson and Crick in 1953.

  • Deoxyribose sugar and the phosphate group from the BACKBONE.

  • A nitrogenous base is attached to each sugar.

• Nitrogenous Bases

  • Adenine

  • Cytosine

  • Guanine

  • Thiamine

• Complementary Base Pairs(Chargoffs rule)

  • A always pairs with T(U in RNA).

  • C always pairs with G

RNA

Difference between DNA and RNA 

1. Single strands(except rRna)

2. Ribose(Instead of deoxyribose)

3. Uracil replaces Thymine 

• mRNA - messenger RNA 

  • carries the message in DNA from the nucleus to the ribosomes

• tRNA - Transfer RNA

  • folded into a T shape and carries amino acids to the ribosomes

• rRNA - ribosomal RNA

  •  RNA + proteins make up ribosomes where proteins are made

DNA and RNA Review 

1.  What are DNA and RNA made of 

   1. Nitrogenous Bases 

2. What is the monomers of DNA and RNA

   1. Nitrogenous Bases 

3. What make up nucleotides 

   1. Nitrogenous base

   2. Phosphate group

   3. Deoxyribose sugar

4. What are the nitrogenous bases in DNA  

   1. Adenine

   2. Cytosine

   3. Guanine

   4. Thiamine

5. What are the nitrogenous bases in RNA 

   1.  Adenine

   2. Cytosine

   3. Guanine

   4. Uracil

6. What bases are paired together ?

   1. A and  T(U)

   2. C and G 

7. Chargoffs rule 

   1. A goes with T and C goes with G 

8. Name of DNA copying itself

   1. DNA replication 

9. When DNA replicates what does each daughter receive

   1. 2 identical copies of the original DNA molecules 

10. How many types of RNA are there? 

    1. 3  

11. What are the names are what do they do 

    1. mRNA - messenger RNA 

       1. carries the message in DNA from the nucleus to the ribosomes

    2. tRNA - Transfer RNA

       1. folded into a T shape and carries amino acids to the ribosomes

    3. rRNA - ribosomal RNA

       1.  RNA + proteins make up ribosomes where proteins are made

12.  Genes contain the instructions for making 

    1. tell cells which proteins to make and when to make them.

13.  What did watson and crick 

    1. DNA or the double helix 

BIG FOUR