Bio Flashcards
Bio sac TERM 1
All living organisms are composed of cells; cells are the basic unit of life; all cells arise from pre-existing cells.
Cell Theory:
Simple, unicellular organisms without a nucleus (e.g., bacteria).
Prokaryotes
Complex, can be unicellular or multicellular, with a nucleus (e.g., plants, animals).
Eukaryotes
Specialized structures within cells (e.g., mitochondria, endoplasmic reticulum, Golgi apparatus).
Cell organelles
Have a cell wall, chloroplasts, and large central vacuoles.
Plant Cells:
Lack cell walls, have smaller vacuoles, and centrioles.
Animal Cells
Surface area to volume ratio affects cell efficiency; smaller cells have a higher SA:Vol ratio, facilitating better exchange of materials.
Cell Shape and Size
Double layer of phospholipids forming the cell membrane; hydrophilic heads face outward, hydrophobic tails face inward.
Phospholipid Bilayer:
Proteins embedded in the membrane that facilitate the transport of substances.
Protein Channels:
Stabilizes membrane fluidity and structure.
Cholesterol
Involved in cell recognition and signaling; attached to lipids or proteins.
Carbohydrates (Glycolipid and Glycoprotein):
Movement of substances without energy (e.g., diffusion, osmosis).
Passive Transport:
Movement of substances against the concentration gradient, requiring energy (ATP).
Active Transport:
Movement of molecules from high to low concentration directly through the membrane.
Simple Diffusion
Movement of molecules across the membrane via protein channels.
Facilitated Diffusion:
Diffusion of water across a semipermeable membrane.
Osmosis:
Process of taking substances into the cell.
Endocytosis:
Process of expelling substances from the cell.
Exocytosis:
Higher solute concentration outside the cell; causes cell to shrink. (doesnt likes water)
Hypertonic:
Lower solute concentration outside the cell; causes cell to swell. (likes water)
Hypotonic
Equal solute concentration inside and outside the cell; no net movement of water.
Isotonic:
The variable that is changed or controlled in an experiment (e.g., concentration of solution).
Independent Variable:
The variable that is measured or observed (e.g., mass of potato).
Dependent Variable
Factors kept constant to ensure a fair test (e.g., temperature, volume of solution).
Controlled Variables
