Cells
What are cells?
The smallest units of life.
What is cell transport?
The movement of substances across the cell membrane either into or out of the cell.
What is osmosis?
a process by which molecules of a solvent tend to pass through a semipermeable membrane from a less concentrated solution into a more concentrated one, thus equalizing the concentrations on each side of the membrane.
Molecules that are able to pass through the membrane.
Permable
Which of the following structures serves as the cell’s boundary from its environment?
a. mitochondrion
b. cell membrane
c. chloroplast
d. channel protein
What is a mitochondria?
The powerhouse of the cell.
What are the 4 types of cell transport?
Simple diffusion, facilitated diffusion, primary active transport and secondary active transport.
What is diffusion?
This process occurs when substances move in and out of the cell from areas of high concentration to areas of low concentration.
Prevents passage of substance across membrane/through bilayer.
Nonpermable
Which of the following is a function of the cell membrane?
a. breaks down lipids, carbohydrates, and proteins from foods
b. stores water, salt, proteins, and carbohydrates
c. keeps the cell wall in place
d. regulates the movement of materials into and out of the cell
What is a organelle?
A structure within a cell that performs a specific function.
Why is transport important to cells?
As cells proceed through their life cycle, a vast amount of exchange is necessary to maintain function.
What is facilitated diffusion?
the passive movement of molecules along the concentration gradient.
Some substances can pass directly through the cell membrane by passive or active transport.
Semipermeable
The cell membrane contains channels and pumps that help move materials from one side to the other. What
are these channels and pumps made of?
a. carbohydrates
b. lipids
c. bilipids
d. proteins
D
What are prokaryotes?
Cells without a nucleus.
What is the main function of transport?
To protect the cell's internal environment and to keep its balance of salts, nutrients, and proteins within a range that keeps the cell and the organism alive.
what is filtration?
the movement of water and other molecules across the cell membrane due to hydrostatic pressure generated by the cardiovascular system.
Movement of a solute from an area of high concentration to an area of low concentration.
Simple diffusion
Diffusion occurs because
a. molecules are attracted to one another.
b. molecules constantly move and collide with each other.
c. cellular energy forces molecules to collide with each other.
d. cellular energy pumps molecules across the cell membrane.
B
What are cell walls and chloroplasts?
The two organelles that are in a plant cell but not in a animal cell.
Name some examples of cell transport.
Phagocytosis of bacteria by Macrophages.Movement of Ca2+ ions out of cardiac muscle cells.Transportation of amino acids across the intestinal lining in the human gut.Secretion of proteins like enzymes, peptide hormones, and antibodies from different cells.
What is the difference between passive transport and active transport?
Active transport involves the movement of molecules from lower concentration to higher concentration with the use of energy. Passive transport involves the movement of molecules from higher concentration to lower concentration and no amount of energy is required.
Diffusion of water through a selectively permeable membrane.
Osmosis
During diffusion, when the concentration of molecules on both sides of a membrane is the same, the
molecules will
a. move across the membrane to the outside of the cell.
b. stop moving across the membrane.
c. continue to move across the membrane in both directions.
d. move across the membrane to the inside of the cell.
C