Bio Unit 3!
What is (are) the main difference(s) between passive transport and active transport?
Active transport requires cellular energy for substances to cross the cell membrane; passive transport does not.
All of the following are types of passive transport except diffusion b. osmosis c. facilitated diffusion d. endocytosis
D endocytosis
Which best describes the role of endocytosis in cell transport?
Endocytosis moves substances into the cell.
How does particle size affect a molecule's transport across a cell membrane?
It is easier for small molecules to diffuse across the cell membrane
What will happen if an animal cell that has a solute concentration of 1% is placed in a 5% saltwater solution?
It will shrink because there is less water outside of the cell than there is on the inside.
What causes the diffusion process to stop?
The concentration of materials inside and outside the cell becomes equal.
A person with swollen gums rinses his mouth with warm salt water, and the swelling decreases. Which has occured?
The water in the gums has moved from a high to a low concentration of water.
The Amazon Sword Plant is a freshwater plant that is commonly used in freshwater aquariums. If this plant is placed in a saltwater aquarium, which of the following is most likely to occur?
Water will exit the plant's cells causing the cell to shrivel as internal pressure decreases.
Which statement is true regarding active transport? a. Substances can move from areas of low concentration to areas of high concentrationThis answer is correct. b. Substances can only move into cells, not out of cells c. Substances do not require additional energy to move in and out of cells. d. Substances can only move across the cell membrane if they are water soluble.
A Substances can move from areas of low concentration to areas of high concentration
Which of the following is an example of osmosis?
a plants roots use osmosis to absorb water from soil
Endocytosis is an example of what type of transport?
active transport
Exocytosis is an example of what type of transport?
active transport
Which example(s) of cell transport does not require chemical energy? a. Drops of blue food coloring are placed in water and spread throughout the water, turning it blue. b. A potato slice is placed in water and water molecules from inside the potato move into the surrounding water.
both answers
Which of these separate the inside of the cell from the surrounding environment?
cell membrane
which of the following does not require energy?
diffusion
In general, in what direction does a diffusing substance move?
down its concentration gradient
Proteins and polysaccharides that are too large to move into a cell through diffusion or active transport move in by
endocytosis
Ridding the cell of materials by discharging the materials in vesicles is called
exocytosis
Which best describes the role of exocytosis in cell transport?
exocytosis moves substances out of the cell
A cell will swell when it is placed in a(n)
hypotonic solution
Transport proteins that allow ions to pass through the cell membrane are called
ion channels
The sodium-potassium pump
is a carrier protein
What is the role of ATP in the process of active transport?
it provides the energy that cells need to move molecules against a concentration gradient.
Suppose that you stayed in the bathtub too long, causing your hands and feet to look wrinkled. What kind of cell transport causes this effect?
osmosis
Osmosis is a type of
passive transport
What process do ion channel use to move ions across the cell membrane?
passive transport
The sodium-potassium pump usually pumps
potassium ions into the cell
In facilitated diffusion, what are the special channels that help substances cross the cell membrane made of?
proteins
A molecule can easily pass through the selectively permeable membrane of an animal cell. Which of these most likely describes the molecule?
the molecule is very small and not charged
Facilitated diffusion allows certain kinds of compounds that are normally blocked by the cell membrane to cross the cell membrane. All of the following are examples of compounds that move by facilitated diffusion except
water
What kind of material is transported through osmosis?
water
What differentiates facilited diffusion from other forms of passive transport?
In facilitated diffusion, a special protein channel helps substances cross the cell membrane.
How do substances move into the cell through endocytosis?
Substances are "engulfed" by a cell's plasma membrane and brought into the cell in a vesicle.