Cell Transport

Define passive transport and list TWO examples of passive transport

1. Passive transport - movement of molecules across the cell that does not require energy. Example) 1. Facilitated diffusion 2. Osmosis

Give two examples of molecules that are transported during facilitated diffusion.

1. Sugars 2. Amino acids

Which picture best depicts osmosis? (see problem 11)

A.

Label each beaker as hypertonic, hypotonic, or isotonic. (see problem 24)

A. Hypotonic B. Hypertonic C. Isotonic

Define active transport and list TOW examples of active transport

Active transport = pumping molecules against their concentration gradient; requires energy. Examples) 1. ion channels 2. endocytosis

Describe what is happening in the diagram of the root cell. (refer to #10)

Active transport is occurring because the mineral ions are being pumped against their concentrations gradient.

What is diffusion? Give two examples of diffusion you could find in every day life.

Diffusion is the tendency for molecules to spread to an equilibrium state. Example) The smell of cookies when baking in the oven, gas exchange from the small intestine into the bloodstream.

Define equilibrium and concentration gradient. Explain how they contribute to cell transport.

Equilibrium = when molecules are evenly dispersed among a space. Concentration gradient = a difference of concentration among a space How do they contribute to cell transport? Molecules with a concentration gradient will move/diffuse until equilibrium is reached.

What process is shown in the diagram below? (see problem 14)

Exocytosis

Osmosis - Direction of movement (from low/high concentrations?)

From high concentrations to low concentrations

Define hydrophobic and hydrophilic

Hydrophobic = water fearing Hydrophilic = water loving

What type of cell environment is depicted below? (see problem 23)

Hypotonic because the water concentration inside the cell is lower than the water concentration outside the cell

What is the role of marker proteins in the cell membrane? (AKA glycoproteins)

Identify the cell

Explain what might happen if the cell membrane became IMPERMEABLE.

If the cell became impermeable, it would die because nutrients would not be able to enter the cell and wastes would not be able to leave the cell.

If the plasma membrane was permeable, but not selectively permeable, how would that affect the cell?

If the cell was not selectively permeable, there might be a buildup of molecules such as ions or waste that could affect its overall health.

Osmosis - Definition in your own words

Osmosis is the diffusion of water

Osmosis Passive or Active Transport?

Passive

Is this an example of active or passive transport? Why or why not? (Look at picture on #3)

Passive transport. Because the molecules are flowing from high concentrations to low concentrations

What process is shown in the diagram below? (see problem 12)

Phagocytosis

Distinguish between pinocytosis and phagocytosis

Pinocytosis occurs when solutes mixed with fluid is taken in by the cell through a vesicle. Phagocytosis, the cell engulfs large debris of food by creating a vesicle

Proteins found in the cell membrane which bind to signal molecules and allow them to pass into the cell

Receptor proteins are found in the cell membrane, which bind to signal molecules and allow them to pass into the cell.

If an infection persists in your sinuses or other nearby areas, it can lead to swelling in the tonsils and adenoids, resulting in a sore throat. The swelling is caused by an inflammatory response to increase blood flow near the site of infection. Sometimes the swelling causes discomfort and painful swallowing. A successful home remedy in treating a sore throat is to gargle salt water. Explain the science behind this technique.

Salt water creates a hypertonic environment; the water concentration outside is lesser than the inside and water leaves the cells. reducing swelling.

Label the underlined parts of the plasma membrane on your answer sheet

See problem 16

What is shown in the picture below? (see problem 13)

Sodium potassium pump

Why are tiny cells more efficient than larger cells?

Tiny cells are more efficient than larger cells because they have a larger volume to surface are ratio; they have more plasma membrane in relation to their cytoplasm and are able to function more efficiently by removing wastes and gaining nutrients.

What is the role of carrier proteins in the plasma membrane? Give one example in which carrier proteins are used.

To assist in transporting molecules across the membrane that are too large to simply diffuse through. Example) Facilitated diffusion

Osmosis - Which molecule is transported?

Water

List the functions of the cell membrane.

a) support the cell and maintain its shape b) support homeostasis/maintain integrity by allowing specific substances into or out of the cell

What process is shown in the diagram below? (see problem 15)

simple diffusion