CELLULAR TRANSPORT Flashcards
the amount of solute in a solution.
Concentration
the dissolved substance in a solution
Solute
a mixture in which two or more substances are mixed evenly.
Solution
the gradual difference in the concentration of solutes in a solution between two regions.
Concentration gradient
ALL cells have a ______ made of proteins and lipids
cell membrane
Plant cells have a cell wall made of _____
cellulose
is fiber in our diet
cellulose is fiber in our diet
Bacteria and fungi also have ____
cell walls
Bacteria and fungi also have cell walls, but they do not contain______
Cellulose
Cell membranes and cell walls are _____allowing water, carbon dioxide, oxygen and nutrients to pass through easily
porous
Cell Membrane aka
“The Phospholipid Bilayer”
ALL cells have a _____ made of Phosphate, proteins, and lipids
cell membrane
All Cells have a cell (______)
plasma membrane
Prokaryotes have
have a cell wall + cell membrane
Eukaryotes have
Animal Cells ( cell membrane only)
Plant cells (cell membrane + cell wall)
cell doesn’t use energy
Passive Transport
cell does use energy
Active Transport
is the movement of small particles across a selectively permeable membrane like the cell
Diffusion
random movement of particles from an area of high concentration to an area of low concentration.
Diffusion
is the diffusion of water through a selectively permeable membrane like the cell membrane
Osmosis
is the movement of larger molecules like glucose through the cell membrane – larger molecules must be “helped”
Facilitated Diffusion
Proteins that form channels (pores) are called
protein channels
diffusion of specific particles through transport proteins found in the membrane
Facilitated diffusion
contain a high concentration of solute relative to another solution (e.g. the cell’s cytoplasm).
Hypertonic Solutions
contain a low concentration of solute relative to another solution (e.g. the cell’s cytoplasm).
Hypotonic Solutions
contain the same concentration of solute as another solution (e.g. the cell’s cytoplasm).
Isotonic Solutions
diffusion of water through a selectively permeable membrane
Osmosis
The solution has a lower concentration of solutes and a higher concentration of water than inside the cell. (Low solute; High water)
Hypotonic Solution
The solution has a higher concentration of solutes and a lower concentration of water than inside the cell. (High solute; Low water)
Hypertonic Solution
The concentration of solutes in the solution is equal to the concentration of solutes inside the cell.
Isotonic Solution
have cell walls that prevent them from over-expanding.
Bacteria and plants
like paramecium has contractile vacuoles that collect water flowing in and pump it out to prevent them from over-expanding.
protist
pump salt out of their specialized gills so they do not dehydrate.
Salt water fish
are bathed in blood. Kidneys keep the blood isotonic by removing excess salt and water.
Animal cells
is the movement of molecules from LOW to HIGH concentration.
Active transport
________as molecules must be pumped against the concentration gradient.
Energy is required
Proteins that work as pumps are called
protein pumps.
transport proteins that require energy to do work
Protein Pumps
changes shape to move molecules: this requires energy!
Protein
is the mechanism by which very large molecules (such as food and wastes) get into and out of the cell
Endocytosis and Exocytosis
Food is moved into the cell by
Endocytosis
Wastes are moved out of the cell by
Exocytosis
White Blood Cells, which are part of the ___surround and engulf bacteria by _____
IMMUNE SYTEM —– endocytosis.
Forces material out of cell in bulk
Exocytosis
membrane surrounding the material fuses with cell membrane
Exocytosis
Cell changes shape – requires energy
Exocytosis
Some cells have membranes and cell walls. what is the example?
Plants, fungi, and bacteria
All cells have a cell membrane made of ____ and_____.
Proteins and Lipids
All cells have a cell membrane made of ____, ______, and ______.
phosphate, proteins, and lipids
It’s a double layer(bilayer) of phosphates, and fats (lipids)
cell membrane
The _____ both repels and attracts water through the membrane at the same time.
Cell membrane
A single phospholipid has _____ (water loving) phosphate heads and _____ (water hating) fatty acid tails.
Hydrophilic, Hydrophobic
Cell membrane separates the components of a cell from its ______ - surrounds the cell
Environment
Cell membrane helps maintain _______ - stable internal balance.
Homoestasis
Gatekeeper
Cell membrane
Regulates the flow of materials into and out of cell - selectively permeable
Cell membrane
Types of cellular transport
Passive transport and active transport
is permeable to water but not to sugar
Semi-permeable membrane
Proteins in the cell membrane form _____ for ______ to pass through
Channels for large molecules
are specific - they “select” only certain molecules to cross the membrane
Transport Proteins
_______ or charged molecules
Transport larger
Facilitated diffusion - (________)
Channel Protein
Diffusion - (________)
Lipid Bilayer
The fluid that surrounds the body cells is _______.
Isotonic
What is the result of hypotonic solution?
Water moves form the solution to inside the cell : CELL SWELSS AND BURST OPEN (CYTOLYSIS)
What is the result of hypertonic solution?
water moves from inside the cell into the solution : cell shrinks (Plasmolysis)
Results of Isotonic solution?
Water moves equally in both directions and the cell remains same size ( dynamic equilibrium)
In _____the pressure exerted on the cell wall is called tugor pressure.
plants
When a cell is placed in a _________, the water diffuses out of the cell, causing the cell to shrivel.
Hypertonic solution
When a cell is placed in an _________, the water diffuses into and out of the cell at the same rate.
Isotonic solution
When a cell is placed in a __________, the water diffuses into the cell, causing the cell to swell and possibly explode.
Hypotonic solution
