Module 1 Flashcards
Cell theory
- All life is made of cells
- Cells are the basic unit of life
- All cells are made from pre-existing cells
- All cells maintain homeostasis (maintenance of a constant internal environment)
Features of prokaryotic cell
• No organelles
• No nucleus
Can be a single cell organism
• Plasmid – DNA (loop of genetic material)
*bacteria, archaea
Features of eukaryotic cell
- Contain membrane bound organelles
- Organelles carry out biochemical processes
- Contains a nucleus (genetic material)
- Can be a single cell organism
Features of both cell types
- DNA
- Ribosomes
- Cytoplasm
- Cell Membrane
Features of plant cell
- Cell wall
- Mostly have chloroplasts
- Rectangular/regular in shape
Features of animal cell
- No cell walls
- Less regular in shape
- Smaller or no vacuole
Features of bacteria
- Contain flagella and pili around the edge of the cell
- Nucleoid
- Oval in shape
Light microscope
- uses visible light and a system of lenses to generate magnified images of small objects
- Both living and non-living specimens can be viewed
Two types of electron microscope
- Scanning electron microscope (SEM)
* Transmission electron microscope (TEM)
Cell size formula
field of view/number of cells = length of each cell
What is the fluid mosaic model
describes the cell membrane as a double layer of lipids, a lipid bilayer with the ability to flow and change shape.
What is osmosis
The movement of molecules from a region of low concentration to a region of high concentration and requires the input of energy through a selectively permeable membrane.
What is diffusion
the movement of a substance from a region where it has a high concentration to a region where it has a low concentration.
Autotroph
need to manufacture their own glucose by the process of photosynthesis e.g. Green plants
Heterotroph
obtain glucose by consuming other organisms and then by the process of digestion breakdown their food into simpler organic compounds including glucose
What is cellular respiration
The series of chemical reactions that occur in the mitochondria, in which oxygen and glucose are combined to produce energy and the waste products carbon dioxide and water
Cellular respiration formula
Glucose + oxygen = water + carbon dioxide + (energy) ATP
What is photosynthesis?
A series of reactions occurring in the chloroplasts by which plants, some bacteria and some protists use light energy trapped by the chlorophyll to produce glucose from carbon dioxide and water
3 factors affecting rate of photosynthesis
light intensity, co2 concentration, temperature
What is metabolic waste
the left-over products of both catabolism and anabolism.
What is an enzyme?
- Enzymes are biological catalysts i.e. they are organic compounds and speed up reactions • Enzymes lower the activation energy so that the reactions can happen much faster.
- Enzymes are critical for living things, as without them, the reactions in the cells would occur too slowly to sustain life.
What does it mean to denature
take away or alter the natural qualities of – loses shape and stops working.
Two enzyme models
lock-in-key + induced fit
Lock-in-key model
- Substrate fits exactly into active site of enzyme to create a reaction
- Only specific substrates can fit into the shape of the active site
Induced fit model
- More accurate accommodates substrate
- Substrate binds to the active site, the site changes shape to accommodate the substrate so they fit in with each other
- Left over material is called a product
Factors affecting enzyme activity
temperature, pH, substrate concentration
X-ray crystallography
Beaming light rays through pure crystals to determine the atomic and molecular structure of a crystal.
Stains
Iodine - Stains carbohydrates in plant and animal specimens brown or blue-black. Stains glycogen red.
Methylene blue - Stains acidic cell parts (like nucleus) blue. Use on animal, bacteria and blood specimens.
Scanning electron microscope:
Use an electron beam to scan across the surface of a non-living specimen.
High magnification and resolution
Transmission electron microscope
- Uses an electron beam to fire through an ultrathin slice of a specimen.
- Two-dimensional
- Extremely high magnification and resolution
