EXAM 3 REVIEW

Enzymes, Organelles, Cell Membrane, Transport

TRANSPORT- movement across the membrane

• Passive Transport• Diffusion• Osmosis• Facilitated Diffusion• Active Transport

• Passive Transport-

• Passive Transport- movement across the membrane that does not require energy. Movement from high to low concentration until homeostasis is met.

• Diffusion-

• Osmosis-

• Diffusion- movement of substances across the cell membrane from high to low concentration.

• Osmosis- movement of water across the cell membrane from high to low concentration.

• Facilitated diffusion-

• Facilitated diffusion- movement from high to low concentration through a protein channel.

• Active transport-

• Active transport- movement across the membrane from a LOW concentration to a HIGH concentration. ENERGY IS REQUIRED. Movement is going against the concentration gradient.

• Active transport- movement across the membrane from a LOW concentration to a HIGH concentration. ENERGY IS REQUIRED. Movement is going against the concentration gradient.

LOW LOW

HIGH

LOW LOW

HIGH

Active Transport

Passive Transport:• Osmosis• Diffusion• Facilitated Diffusion

Which molecules are permeable to the cell membrane?

• Starch?• Glucose?• Starch Indicator?• Water?

Which molecules are permeable to the cell membrane?

• Starch? NO• Glucose?• Starch Indicator?• Water?

Which molecules are permeable to the cell membrane?

• Starch? NO• Glucose? YES• Starch Indicator?• Water?

Which molecules are permeable to the cell membrane?

• Starch? NO• Glucose? YES• Starch Indicator? YES• Water?

Which molecules are permeable to the cell membrane?

• Starch? NO• Glucose? YES• Starch Indicator? YES• Water? YES

Which macromolecule is an enzyme?

Which macromolecule is an enzyme?

•PROTEIN

What does an enzyme do?

What does an enzyme do?

• Enzymes speed up, or catalyze chemical reactions in living things.

How many different chemical reactions can an enzyme catalyze?

How many different chemical reactions can an enzyme catalyze?

• ONE.

WHY???

How many different chemical reactions can an enzyme catalyze?

• ONE.

• Every enzymes has a SPECIFIC shape that can fit specific reactants only.

• EXAMPLE??

How many different chemical reactions can an enzyme catalyze?

• ONE.

• Every enzymes has a SPECIFIC shape that can fit specific reactants only.

• EXAMPLE- The enzyme catalase speeds up the breakdown of hydrogen peroxide ONLY.

What are 2 factors that affect how well an enzyme works?

What are 2 factors that affect how well an enzyme works?

• Temperature• pH

What happens if the temperature or pH becomes too extreme for an enzyme?

What happens if the temperature or pH becomes too extreme for an enzyme?

• The enzyme loses its specific shape and can no longer speed up chemical reactions. It stops working!

Explain how enzymes are specific

Explain how enzymes are specific

• Every enzyme has a specific shape• This shape only fits specific reactants• Each enzyme catalyzes a specific chemical

reaction• Enzymes only work in specific temperatures

and specific pH levels

Organelles

• Cell membrane• Cell wall• Cytoplasm• Nucleus• Mitochondria• Ribosome• Chloroplast• Vacuole

• Explain what happens to cells when put in a highly concentrated solution (lots of dissolved substances, little water).

• NAME 3 EXAMPLES OF WHERE WE SAW THIS IN CLASS

• NAME 3 EXAMPLES OF WHERE WE SAW THIS IN CLASS

• Gummy Bears in salt water- shrank• Egg in corn syrup- decreased in size• Onion cell in salt water- cell membrane

shriveled

• NAME 3 EXAMPLES OF WHERE WE SAW THIS IN CLASS

• Gummy Bears in salt water- shrank• Egg in corn syrup- decreased in size• Onion cell in salt water- cell membrane shriveled

Why did all of these cells get smaller? What was lost from all of these cells?

• NAME 3 EXAMPLES OF WHERE WE SAW THIS IN CLASS

• Gummy Bears in salt water- shrank• Egg in corn syrup- decreased in size• Onion cell in salt water- cell membrane shriveled

Why did all of these cells get smaller? What was lost from all of these cells?

WATER MOVED OUT OF THE CELLS

What happens to cells that are put in distilled, or pure water? (100%) Water

What happens to cells that are put in distilled, or pure water? (100%) Water

• Water flows INTO the cells.

What happens to cells that are put in distilled, or pure water? (100%) Water

• Water flows INTO the cells.

• There is a HIGH concentration of water outside the cell, so it flows to where there is a LOWER concentration of water inside the cell.