Unit One Flashcards
Prokaryote
A single-celled organism with no organelles
Eukaryote
Single to multi-cellular organism with organelles
Animal Cells
No cell wall, no cholorplasts, roundish shape
Plant cells
Cell wall, cholorplasts, squared shape.
Binary Fission
Prokaryote splitting into 2 identical cells
Plasma Membrane
Selectively permeable, and regulates the movement of substances in and out of cells.
Phospholipid
A macromolecule with a phosphate head and two fatty acid tails
Integral Proteins
A special functional region for the purpose of securing its position within (inside) the cellular membrane, hydrophobic.
Peripheral Proteins
attach to the outer surface of the cell membrane, hydrophilic.
Glycoproteins
Have sugar units attached to the outer surface of the membrane. Used for identification, recognition, and cell-to-cell communication.
Pump or Channel Proteins
Similar to integral proteins, but allow for molecules and other substances to pass through the cell membrane
Cholesterol
A steroid that is only in animal cell membranes: reduces the fluidity of the membrane, making it stiffer at high temperatures
Simple Diffusion
smaller substances move between the phospholipid molecules in the cell membrane from HIGH to LOW concentration.
Facilitated Diffusion
larger substances move through CHANNEL PROTEINS in the cell membrane from HIGH to LOW concentration
Osmosis
facilitated diffusion of WATER (water moves from HIGH to LOW concentration through specialized channel proteins called Aquaporins)
Hypotonic
Inside of the cell has LESS water (and more salt/sugar/substances) than outside the cell; Water moves into the cell.
Isotonic
Same water and salt both inside and outside of the cell.
No change in water movement
Hypertonic
Inside of cell has MORE water (and less salt) than outside of the cell.
Water moves OUT of the cell.
Active Transport
substances move across membranes through a pump protein from LOW to HIGH concentration using energy from ATP
Exocytosis
Vesicles fuse with the plasma membrane, releasing their contents outside of the cell
Endocytosis
Small pieces of the plasma membrane pinch off to create a vesicle containing materials from outside the cell and carry them inside the cell
cell eating = phagocytosis
cell drinking = pinocytosis
Cell Theory
All cells are formed from pre-existing cells
The Genetic Code
the 64 codons that have the same meaning in the cells of ALL organisms on Earth.
Bubble Model
gases released by volcanoes and hydrothermal vents under the sea helped to create the first biomolecules that eventually became life.