Chapter 3 Exchanging Materials in the Environment

The experiment setup shows a solution with differing concentrations of solute separated by a selectively permeable membrane. The membrane is permeable to solute but not the water. (true or false)

False

Two forms of Exocytosis and Phagocytosis and Pinocytosis. (true or false)

False

Water, carbon dioxide, oxygen, and some other substances can pass through the cell. (true or false)

False

Diffusion occurs because... a. Molecules are attached 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

Molecules constantly move and collide with each other

A cell membrane must be selectively permeable so that the cell can exert some level of control over which types of molecules can pass through the membrane. (true or false)

True

A cell's relatively constant internal physical and chemical conditions are called homeostasis. (true or false)

True

A wilted plant suggests that too much water has left the plant. (true or false)

True

An organism is a protected compartment in the sense that whether it is made of a single cell or many cells, each cell is completely surrounded by a protective membrane. (true or false)

True

At equilibrium, Side A will have less water than Side B and the concentration of solute molecules will be equal on either side of the selectively permeable membrane. (true or false)

True

Both are forms of active transport of large molecules carried out by movements of the cell membrane. Endocytosis involves taking materials into the cell, whereas exocytosis involves moving materials out of the cell. (true or false)

True

Cell membranes must control the exchange of nutrients, waste water, and communication signals. (true or false)

True

During Phagocytosis, extensions of cytoplasm surround a particle and package it within a food vacuole. The cell engulfs it and requires a considerable amount of energy. (true or false)

True

During Pinocytosis, tiny pockets form along the cell membrane and fill with liquid that pinches off to form vacuoles within the cell. (true or false)

True

Facilitated diffusion involves the movement of molecules across a membrane through protein channels. The molecules move from an area of high concentration to an area of low concentration. Facilitated diffusion does not require additional energy. Active transport is the movement of particles across the cell membrane using energy. Molecules can move from an area of low concentration to an area of higher concentration in active transport. Osmosis is an example of facilitated diffusion. (true or false)

True

If an animal cell with an internal salt concentration of 0.8% is placed in a salt solution with a concentration of 0.2%, the cell would swell and burst because the 0.2% salt solution is hypotonic with respect to the cell, causing a net movement of water into the cell. (true or false)

True

If you add a teaspoon of sugar to a cup of coffee, and the sugar molecules disperse themselves throughout the hot coffee. Diffusion has occurred; because diffusion is the movement of a substance from an area of high concentration to an area of low concentration. (true or false)

True

In a Hypertonic Environment, the cells crenate/shrink due to the high solute concentration and low water molecule concentration. (true or false)

True

In a Hypotonic Environment, the cells swell/lyse due to the high water molecule concentration and low solute concentration. (true or false)

True

In an Isotonic Environment, the concentration of solutes in the solution is equal to the concentration of collates inside the cell. (true or false)

True

In the lipid bilayer cell membrane, the fatty tails non-polar and hydrophobic (water fearing). (true or false)

True

In the lipid bilayer cell membrane, the phosphate head is polar and hydrophilic (water loving). (true or false)

True

Large molecules, such as glucose, that cannot cross the lipid bilayer can still move across the membrane through a type of passive transport called facilitated diffusion. (true or false)

True

Once equilibrium is reached in the apparatus shown in Figure 7-10, the water molecules will continue to move across the membrane; however; there will not be a new movement from one side to the other. (true or false)

True

Once the equilibrium is reached, roughly equal numbers of molecules move in either direction across the semipermeable membrane, and there is no further change in concentration on either side of the membrane. (true or false)

True

Polar molecules are prevented from passing through the membrane unaided while nonpolar molecules can move more freely. (true or false)

True

The cell takes in food and water and eliminates wastes through its selectively permeable cell membrane. (true or false)

True

The cell would die because needed nutrients, such as food and water could not get inside the cell and wastes would accumulate inside the cell. (true or false)

True

The difference in lines A and B in the graph in Figure 7-12 could be because the lab group (line A) might have used a moe concentrated solution of sucrose or a membrane with a different permeability. (true or false)

True

The membrane is permeable to water so water can cross the membrane in both directions. Over time, there will be a new movement of water toward Side B, which has a higher concentration of solute particles. (true or false)

True

The solution on Side A has fewer solute particles than the solution on Side B. Both solutions have the same amount of water, so the solution on Side A is hypotonic compared to the solution on Side B. (true or false)

True

When a normal red blood cell is placed in a hypertonic solution, one that has a higher solute concentration than inside the cel, there is a net movement of water out of the cell. The cell will shrink due to osmotic pressure. (true or false)

True

line A shows that the single groups result are quite different from the results of the rest of the class. Over a half-hour period, the lab group found that the solution traveled 25 mm, whereas the rest of the class found a distance of only 12 mm over the same period of time. The distance traveled in the lab group's data also kept increasing, where as the class' data leveled out at about 10 minutes. (true or false)

True

Which of the means of particle transport requires input of energy from the cell? a. diffusion b. osmosis c. facilitated diffusion d. active transport

active transport

Which pf the following structures serves as the cell's boundary from its environment? a. mitochondria b. cell membrane c. chloroplast d. channel protein

cell membrane

Which means of particle transport is shown in Figure 7-5 above? a. endocytosis b. exocytosis c. facilitated diffusion d. protein pump

endocytosis

Which means of particle transport is shown in Figure 7-4 above? a. diffusion b. osmosis c. facilitated diffusion d. active transport

facilitated diffusion

The diffusion of water across a selectively permeable membrane is called. a. osmotic pressure b. osmosis c. pinocytosis d. active pressure

osmosis

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

proteins

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 amount of materials into and out of the cell

regulates the amount of materials into and out of the cell

An animal cell that is surrounded by fresh water will burst because of the osmotic pressure causes... a. water to move into the cell b. water to move out of the cell c. solutes to move into the cell d. solutes to move out of the cell

water to move into the cell

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 the cell

Continue to move across the membrane in both directions

A raisin placed in a cup of pure water overnight will puff up with water. The concentration of water in the cup is lower than the concentration of water in the raisin, water will flow out of the raisin and into the cup. (true or false)

False

Active transport is the transport of molecules down their concentration gradient and is accomplished without the input energy. (true or false)

False

During Endocytosis, a membrane of the cackle surrounding the material fuses with the cell membrane and forces the contents out of the cell. (true or false)

False

Molecules of larger size often can diffuse freely across the cell membrane. (true or false)

False

Molecules tend to move from an area where they are more concentrated to an area where they are less concentrated. This process is called osmosis. (true or false)

False

Moving materials from an area of low concentration to an area of high concentration requires passive transport (true or false)

False

Passive transport uses energy supplied by ATP to move molecules against their concentration gradient. (true or false)

False

Smaller molecules may require a specific transport protein to assist their movement. (true or false)

False

Some materials can move across the cell membrane against a concentration gradient by passive transport. (true or false)

False