Unit 3 Flashcards
(12 cards)
What is a cell?
The basic unit of life.
Which macromolecules are responsible for the cell membrane?
Lipids (phospholipids) and proteins.
Why do phospholipids create a double layer?
Hydrophilic heads face water; hydrophobic tails face inward.
What is the difference between a eukaryote and a prokaryote?
Eukaryotes have a nucleus and organelles; prokaryotes do not.
What are the different organelles?
Examples:
* Nucleus (DNA storage)
* Mitochondria (energy)
* Ribosomes (protein synthesis)
What is simple diffusion?
Movement of molecules from high to low concentration.
What is facilitated diffusion?
Passive transport through proteins.
What is active transport?
Movement against a concentration gradient using energy (ATP).
What is endocytosis?
Cell engulfing material.
What is exocytosis?
Expelling material.
What is osmosis?
Diffusion of water across a semi-permeable membrane.
What role does SA:V play in organisms?
Maximizes exchange of materials and waste.
