Biology Notes
Cytology and Lab Techniques
Chapter 7
Prokaryotes: Bacteria. Lack membrane-bound organelles (no nucleus, no mitochondria, etc)
Eukaryotes: Animals, plants, fungi, protists.
Lysosomes: Digest foreign invaders and organelles and cells that have outlived their usefulness.
Diffusion: High to low concentration
Osmosis: Water flows from low to high concentration
Active transport: When a material goes from an area of low concentration to an area of high
concentration. (Opposite of diffusion).
Homeostasis: Equilibrium
Assessment
All cells have DNA and a cell membrane.
All single-celled organisms reproduce
Phospholipid bilayer: Makes up the membrane of cells.
Chapter 8
ATP (adenosine triphosphate): The main source of energy, which is held in phosphate bonds.
Photosynthesis: Sunlight converted by plants into energy stored in sugars.
Chlorophyll: The pigment molecule that captures sunlight in chloroplasts in plants.
Electron carriers: Transfers high-energy electrons (from photosynthesis or cellular respiration)
from one molecule to another. Examples: NADH, NADPH, FADH2
Light-dependent reactions: Make energy (ATP). Use energy from the sun to produce oxygen,
ATP, and NADPH
Light-independent reactions (Calvin Cycle): Make sugar. The products of the light-dependent
reactions (ATP and NADPH) are used to produce sugars.
Assessment
Mushrooms are not plants. They’re fungi, meaning they get their energy from other living
things.
A single molecule of glucose stores more than 90 times the energy stored by ATP.
Chlorophyll reflects green light (back to your eyes) which is why you see plants as green.
NADPH is a source of energy for the Calvin Cycle (also known as the light-independent
reactions)
ATP Synthase: Creates ATP when H+ ions pass through it (from high concentration to low
concentration).
CAM plants survive in hot, dry conditions.
Chapter 9
Glycolysis: Breakdown of glucose to create energy (ATP) and two molecules of pyruvic acid.
Krebs Cycle: Pyruvic acid from glycolysis gets broken down to release CO2. Some ATP is
generated and many electron carriers are “reloaded” in preparation for the electron transport
chain.
Cellular Respiration
Glycolysis  Krebs Cycle  Electron Transport Chain. Net gain: 36 ATP (for every one glucose
you put in)
Cellular respiration: uses glucose from food and oxygen to generate ATP.
Glycolysis takes place in the cytoplasm.
Krebs Cycle and Electron Transport Chain take place in the mitochondria.
Alcoholic Fermentation: A metabolic process in plants to create energy in the absence of
oxygen. Produces alcohol.
Lactic Acid Fermentation: A metabolic process in animals to create energy in the absence of
oxygen.
Cells use the energy available in food to make ATP.
Each gram of glucose contains approximately how much energy? 4 Calories
The electron transport chain uses the high energy electrons from the Krebs Cycle to move H+
ions across the inner mitochondrial membrane.
Overview:
You get glucose from eating food, then the glucose enters the cell and is broken down by
glycolysis. The products (pyruvic acids) enter into the Krebs Cycle, which regenerates electron
carriers like NADH and FADH2. These electron carriers move on to the electron transport chain
where they give up their H+ so that they can form an area of high H+ concentration. These H+
then fall down their concentration gradient by passive transport through the ATP synthase
which creates ATP in the process.
Anaerobic: Minus oxygen.
Oxygen debt: This is the amount of oxygen needed to oxidise lactic acid to carbon dioxide and
water.
Chapter 10
Large cells are less efficient when it comes to moving materials across the membrane.
DNA exists in the form of chromatin (like a mass of stringy spaghetti) most of the time, and only
condenses into X-shaped chromosomes for cellular division. (makes even division of genetic
material possible).
Mitosis:
Prophase: Chromatin condenses into chromosomes.
Metaphase: Chromosomes line up at the center of the cell.
Anaphase: The chromosomes separate (think ANA = AWAY)
Telophase: The chromosomes decondense back into chromatin.
Cytokinesis: The cell pinches off and forms two new cells. The last part of the process.
Mitosis (below): Produces identical daughter cells.
Cytokinesis (below)
Centromere: The middle of the X in a chromosome, where the spindle fibers attach
The rate at which materials enter and leave the cell depends on the cell’s surface area.
Cyclin is a family of proteins that control the progression of cells through the cell cycle
Which statement does NOT describe external regulatory proteins? A. They respond to events
occurring inside a cell.
Bone marrow cells that produce blood cells are best categorized as __________. B. Adult stem
cells.
Which type of cell has the potential to develop into any type of cell? A. Totipotent.
MORE NOTES ON NEXT PAGE
Worksheet: The Plasma Membrane: Structure and Functions
Contractile vacuoles have to work harder for a cell in distilled water (than contractile vacuoles
in pond water) because the concentrations are very different, so water will rush into the cell
more rapidly when it’s in distilled water.
Phage: Eat
Pino: Drink
Phagocytosis: Cells eating things.
Pinocytosis: Cell drinks some kind of liquid.
Cytoskeleton: Made up of microtubules, intermediate filaments, and microfilaments
Peroxisomes and lysosomes break down toxic materials with acids and peroxides.