Unit 2 Outline Flashcards
mitochondria
transfers energy from organic compounds to ATP
ribosomes
organizes the synthesis of proteins
endoplasmic reticulum
prepares proteins for export (rough ER); synthesizes steroids, regulates calcium levels, breaks down toxic substances (smooth ER)
golgi apparatus
processes and packages substances produced by the cell
microfilaments and microtubules
contribute to the support, movement, and division of cells
cilia and flagella
propel cells through the environment; move materials over the cell surface
nucleus
stores hereditary information in DNA; synthesizes RNA and ribosomes
cell wall*
supports and protects the cell
vacuole*
stores enzymes and waste products
plastid* (chloroplast)
stores food or pigments; one type (chloroplast) transfers energy from light to organic compounds
passive transport
The movement of molecules across a cell membrane without energy input from the cell. The molecules will move from an area of high concentration to an area of low concentration. This can also be referred to as moving down the concentration gradient.
active transport
drives molecules across a membrane from a region of lower concentration to a region of higher concentration or against a concentration gradient. This process requires energy.
diffusion*
The movement of molecules in a fluid or gas from a region of high concentration to an area of low concentration.
- passive
« Examples of Diffusion:
• If you encounter a truck full of pigs, the manure odor will diffuse through the air to your nose.
• Food colouring drops added to a beaker of water will diffuse through the water without energy being added, (agitation or heat)
• Cells continually consume oxygen which means the oxygen concentration is almost always higher outside a cell than it is inside a cell. As a result, oxygen diffuses into a cell without the cell expending any energy.
osmosis*
diffusion of water across a selectively permeable membrane. Is a form of passive transport. Water will always move toward where there are more solutions.
hypotonic*
when concentration of solute molecules outside the cell is lower than inside the cell (in the cytosol) so the solution is hypotonic to the cytosol. (Passive)
- Potato in distilled water
- H2O moves into potato
- Potato will swell and get harder
hypertonic*
when concentration of solute molecules outside the cell is higher than inside the cell, so the solution outside is hypertonic to the cytosol (passive)
- Potato in salt water
- H2O moves out of potato
- Potato will shrivel/get softer
isotonic*
when the concentration of solute molecules inside and outside the cell are equal . Water diffuses into and out of the cell at equal rates. (Passive)
- Potato in tap water
- H2O moves in and out at same rate
- Potato stays same