Sapling Biology Ch. 5

The movement of ions through a membrane protein is an example of what?

active transport

Phospholipids are molecules that have two regions, the head and the tail, with distinct chemical properties. Classify the following descriptions as characteristics of the heads or tails of phospholipids.

best be lookin at that Sapling fam

Cell membranes are composed of phospholipids that have head and tail regions. The phospholipid head is hydrophilic and spontaneously orients toward the environment. Which of the following phrases best describes the hydrophilic region of a phospholipid?

interacts with water

Label the parts of a cell and describe each part:

look in sapling homework for image (cause quizlet is big stupid)

What is the term for cellular ingestion of large particles or cells?

phagocytosis

One way that cells engulf material from the environment is by ingesting solutes in the aqueous environment and enclosing them in intracellular vesicles. What is the name of this method of ingestion?

pinocytosis

What is a function of cholesterol in a cell's plasma membrane?

regulating membrane fluidity

What does the fluid mosaic model describe about the structure of plasma membranes?

1) A membrane has proteins and other components embedded among the phospholipids 2) Individual phospholipids are not strongly attached to neighboring phospholipids.

Exocytosis is one of the processes living organisms use to move molecules. Choose all the examples of exocytosis.

1) A single-celled eukaryotic organism excretes digestive waste into surrounding water 2) A nerve cell releases peptides used as messengers into the extracellular space 3) Proteins used as hormones are moved out of the cell in which they were manufactured

Descriptions that apply to a sodium-potassium group:

1) ATP is necessary for its functioning 2) Pump moves potassium ions into the cell and sodium out of the cell

What are some properties of exocytosis?

1) It is a primary method of transporting large particles out of the cell 2) It secretes materials from the cell through the fusion of a vesicle with the plasma membrane

How would you describe endocytosis?

1) The cell membrane forms a vesicle around a particle in the cytoplasm and engulfs it 2) The cell expends energy to transport materials into the cytosol

What are two properties of protein-facilitated active transport?

1) The cell spends energy to move substances through a protein across the plasma membrane 2) Substances can be moved across the plasma membrane against a concentration gradient

What word best describes facilitated diffusion?

Passive Transport

A selectively permeable membrane divides a container in half. One half of the container, Side A, is filled with a starch solution, while the other half, Side B, is filled with an iodine tincture. Starch is a large macromolecule that forms a milky white solution when dissolved. An iodine tincture contains very small iodide ions and is a brown solution. Iodide ions turn dark blue when they react with starch molecules. After several hours, Side A is dark blue, while Side B is brown. Which statement describes the diffusion of solutes through the membrane?

The membrane excluded the starch molecules, but the iodide ions diffused through

What best describes diffusion?

The movement of a substance from a region where it is more concentrated to a region where it is less concentrated down its concentration gradient

The plasma membrane is an outer boundary that separates the interior of a cell from its external environment and is found in all cells. The molecules that make up the plasma membrane have a unique quality that helps to ensure the integrity of the cell. Considering the structure of the plasma membrane, what best explains why human cells do not dissolve in water?

The plasma membrane is composed of phospholipids, which have hydrophobic regions

What sentence would describe an electrochemical gradient?

The sum of the differences in charge and chemical concentration of ions across a membrane

What does a uniporter, symporter, and antiporter do?

Uniporter: transports 1 substance only 1 direction Symporter: Can move two types of proteins one direction out of the cell Antiporter: Can move a type of protein in and another type of protein out

Match each of the following characteristics to the part of the lipid bilayer having that property.

Again, look at Sapling cause f quizlet

What are examples of facilitated diffusion?

Any answer that has "flowing down connection gradient" is correct. There are 3 possible answers but all quite wordy, so it's probably easiest to look at Sapling for this one.

Somehow I am off in my numbering for Sapling questions because number 1 has gone missing. In conclusion, what is the reason for this?

Both Jessi and Sapling are also stupid.

What does a cell look like in an isotonic, hypertonic, and hypotonic solution?

Cell in isotonic solution: normal/healthy Cell in hypertonic solution: shriveled up Cell in hypotonic solution: engorged/swollen