Chapter 3 Flashcards
What is pinocytosis?
Endosomes filled with extra cellular fluid
What is phagocytosis
Phagosomes containing solid objects that may be as large as the cell itself. In this process cytoplasmic extensions called pseudopodia; surround the object and their membranes fuse to form a phagosome
What is exocytosis
A vehicle formed inside the cell fuses with and becomes part of the plasma membrane.
What is concentration gradient?
The difference between the high and low concentrations
Under what conditions gradients can be increased or decreased?
Distance, molecule size, temperature, electrical forces
What is osmosis?
Net diffusion of water across a membrane
What is osmotic pressure?
An indication of the force with pure water moves into that solution as a result of its solute concentration
What is isotonic?
A solution that does not cause osmotic flow of water in or out of a cell
What is hypertonic?
Has more sokutes and gains water by osmosis; cell shrinks and shrivels; crenation
What is hypotonic?
Has less solutes and loses water through osmosis- cell swells; hemolysis
What is active transport?
A high energy bond- provides energy needed to move ions or molecules across the membrane- endocystosis, pinocytosis, phagocytosis, excytosis
What is passive transport?
Requires no energy- diffusion, osmosis, facilitated diffusion
What is mitosis?
The division of a single cell nucleus that provides two identical daughter cells nuclei and essential step and cell division
What is meiosis?
Cell division that produces gametes with half the normal somatic chromosome complement
What is differentiation
The gradual appearance ofcharacteristic cellular specialization during development as the result of gene activation or repression