The flashcards below were created by user
on FreezingBlue Flashcards.
short, and many found all around the border or entire cell, they all beat rhythmically (coordinated in one direction)
long, singular or several, found on both Bacteria and Eukaryotes, means on cell movement through liquid
Bacterial Flagella are composed of? and motion is? Are they surrounded by plasma membrane?
Rotates like "ship propeller"
They are not surrounded by plasma membrane
Eukaryotic Flagella are composed of? and motion is? Are they surrounded by plasma membrane?
Protein: Microtubules in a 9+2 arrangement.
By undulation: side-to-side motion.
Yes they are surrounded by a plasma membrane.
groups of cells working collectively and ex. would be muscle tissue.
What issues faced with muticellularity?
1) cell-to-cell adhesion
2) communication between cells of an organism
What structures enhance adhesion? And what are they called?
Between plant cells called Pectin
Between animal cells called Integrins
What are found in animal cells
layers of gelatinous polysaccharides connected to cytoskeleton of adjacent cells
Tight Junctions (observed in epithelial tissues) Cell-to-cell attachments proteins line up and bind (water tight)
Special proteins in cell membrane of adjacent cells: Desmosomes (in epithelial and muscle)
What links the cytoskeleton?
What are Gap Junctions?
in animals they are formed by a specialized protein that creat channels between cells these channels allow water, ions, and small molecules to move between adjacent cells
What are plasmodesmata?
In plants they are communication portals, they are gaps in the cell walls create direct communication between the cytoplasm of adjacent cells.
What are the structures which enhance cell-to-cell communication?
In Plants: Plasmodesmata
In Animals: Gap Junctions
What is Diffusion?
If a molecule is physically capable of crossing the cell membrane, it simply diffuses across from the higher to lower concentration
What is the act of diffusion referred to?
Moving along a concentration gradient
What is the primary component of cell membranes?
Examples of substances/ molecules that can diffuse across cell membrane?
Breathing, steroid hormones
A special type of diffusion where only water molecules are diffusing across the cell membrane. Ex. Sugars and salts
The cell membrane is semipermeable which means?
It controls the passage of materials
In nature there are three possible scenarios for cells what are they called?
- Hypertonic Soln.
- Hypotonic Soln.
- Isotonic Soln.
What is Hypertonic Soln.?
Soln. surrounding/bathing cells has a higher # of solutes than inside of the cell
What is Hypotonic Soln.?
Soln. surrounding/bathing the cell has a lower # of solutes than inside the cell
What is Isotonic Soln.?
Soln. surrounding/bathing the cell is equal to the # of solutes as inside the cell
What is Mediated Transport and which cell membrane structure would enable this?
When a molecule or substance that cnnot physically cross the cell membrane but must to sustain life. It need "help" crossing using a structure called a Protein channel
What are the two major types of mediated transport?
- Facilitated diffusion
- Activation Transport
What is facilitated Diffusion and give ex?
A molecule is transported from high to low however the transporter must assist the molecules through the membrane. Ex blood glucose/diabetes diagram
Explain Activation Transport and give an ex?
Molecules are transported across the cell membrane against the # gradient. (from low to high) Because this goes against the way molecules move in nature it requires cellular energy to pump these molecules across. Ex Na/K ( sodium and potassium) pump in animals
Endocytosis is and give ex?
The cell brings material/cell inside by engulfing it. Ex WBC
Exocytosis is and give ex
The cell moves materials out of the cell within a membranous vesicle. The vesicle mambrane "fuses" with the cell membrane and the material is released outside of the cell. Ex waste, hormones, insulin