chapter 3 learning objectives Flashcards
List the structural features common to all cells (prokaryotic and eukaryotic).
All cells have DNA, RNA (reproduction of proteins), ribosomes, a lipid ridge cell membrane, cytoplasm, cytosol, and they are all small in size.
State the 3 principles of the cell theory.
The ideas that all living matter consists of cells, cells are the structural, and functional units of life, and all cells come from preexisting cells.
Define “organelle”
organelle is a compartment of eukaryotic cell performs a specialized function.
what does the nucleus contain?
DNA, contains the nucleolus and is surrounded by the nuclear
envelope.
what is the difference between a the nucleus and the nucleolus
the nucleolus is in the nucleus and components of ribosomes are assembled in there
what are cilia and flagella are made of and where are they located?
cilia and flagella are made of microtubules and are located on the outside of cells.
Which cells have a cell wall? What is it made of in each case?
Plant cells have a cell wall it is made of cellulose filaments.
Describe the structure of phospholipids. Which part is nonpolar/hydrophobic?
Which part is
polar/hydrophilic? Phospholipids are made of 2 fatty acid chains and a glycerol head. The glycerol is hydrophilic and the fatty acid chains are hydrophobic.
what is a tight junction? and give an example
Tight Junction: fuses the cell together to form an impermeable barrier between them. Proteins anchored in membrane connect to actin in the cytoskeleton and join cells into sheets.
Example;tight junctions prevent stomach acid form seeping into tissues surrounding the stomach
what is an anchoring or adhering jucntion
connects animal cell to its neighboring or extracellular matrix, somewhat like a rivet. Proteins at each junction span the cell membrane and link to each cell’s cytoskeleton.
Example:anchoring junctions hold skin cells in place by anchoring them into cellular matrix
what is a gap junction and give an example
is a protein channel that link the cytoplasm and adjacent animal cells, allowing, exchange of ions, nutrients, and other small molecules.
link heart muscles cells to one another, allowing groups of cells to contract together
- Name the 3 types of cellular junctions described in the textbook. Which cells have them?
Tight junction, anchoring junction/ adhering and gap. Animal cells have them.
List the 3 components of the cytoskeleton. Describe the size and protein makeup of each.
Microfilaments, intermediate filaments, and microtubules.
Microfilaments is a long rod of protein actin.
Intermediate filaments: 10-nanometer diameter. Made of a variety of proteins.
Microtubules: composed of a protein called tubulin, It is assembled into a hollow tuber that is 23 nanometers in diameter.
