Quiz #7 (Cells) Flashcards
What is the functions for cell membrane?
- Forms barriers for chemical reactions
- Controls what goes in and out of cell
What does selectively permeable mean?
allows some substances to cross but not others
What is the cell membrane made of?
Phospholipids
How to describe the interior of a cell?
Interior is water “fearing” (hydrophobic fatty acids)
How to describe the exterior of a cell?
Exterior is water “loving” (hydrophilic phosphate group)
What things are rejected by the cell membrane?
large molecules, charged particles (ions), and polar molecules (water)
What things can pass through the cell membrane?
Small molecules, and non polar
What is a mosaic?
A surface made of small fragments
What are glycoproteins?
Acts as identification markers for cell to cell communication
What do protein channels do?
Move substances that are rejected by the cell membrane into the cell membrane
How do molecules pass through the cell membrane?
Passive or active transport
What is simple diffusion?
Particles moving from a place with high concentration to low concentration
What is concentration gradient?
The difference in concentration on 2 sides of the membrane
What is passive transport?
No energy needed for this - molecules moving from high to low concentration
What is facilitated diffusion?
Type of passive transport that uses special proteins to move molecules across the membrane
What is diabetes?
inability for glucose to pass through glucose channel
What is cystic fibrosis?
inability of chloride ions to pass through chloride channels
What is osmosis?
The diffusion of water across a membrane
What is tonicity?
The relationship between solution inside and outside a cell
What does it mean when the solutions are isotonic?
The 2 solutions are equal in solute
What does it mean solutions are hypotonic?
The solution with lower concentration (will move to where there is less water) - the cell will burst
What does it mean when solution are hypertonic?
The solution with higher solute (will to move to where there is less water) - the cell will shrink
What is active transport?
an energy requiring process moving molecules from a low concentration to a high concentration - ATP is responsible for this
What is exocytosis?
Exiting out of cell by membrane bound vesicles
What is endocytosis?
Taking things into the cell by infoldings or pockets of the cell membrane
What is phagocytosis?
The cell membrane wrapped around food/prey until it is packaged inside a vacuole
What are the types of endocytosis?
Phagocytosis, Receptor mediated, pinocytosis
What is an organelle?
Membrane bound structure that carries out specific functions in cell
What is the function of nuclear pore?
allows RNA to travel to ribosomes
What are vesicles?
tiny membrane bound sacs that allow materials to be shipped through cell/system
What is the endomembrane system?
allows particles (proteins, lipids, hormones) to move within and out of cell
What do vacuoles do?
allow for the isolation of materials
