Vacuoles and Energy Houses

Q: What are vacuoles?

Vacuoles are large sacs of membrane or vesicles that bud from the ER, Golgi bodies, or plasma membrane

Q: What functions do vacuoles serve?

Vacuoles have a variety of functions, depending on the cell type

Q: What is the central vacuole in plant cells?

The central vacuole is a versatile compartment in plant cells that stores organic nutrients and poisons

Q: How much of a plant cell's volume can the central vacuole occupy?

The central vacuole can take up to 90% of the cell's volume

Q: What is the central vacuole filled with, and what does it provide?

The central vacuole is filled with cell sap, which provides added support

Q: How does the central vacuole contribute to plant growth?

The central vacuole absorbs water, causing plant cells to expand and contributing to plant growth

Q: What does the central vacuole contain that affects its pH?

The central vacuole contains salts, sugars, and weak acids, making its pH somewhat acidic

Q: What specialized vacuoles are found in some protists?

Contractile vacuole: Rids the cell of excess water

Digestive vacuoles: Break down nutrients.

Q: Why do cells require energy houses?

Cells require energy houses to manage ATP production, which is vital for cellular processes

Q: What are mitochondria?

Mitochondria are organelles found in all eukaryotic cells that produce ATP during cellular respiration

Q: Does the number of mitochondria in a cell remain constant?

No, the number of mitochondria varies based on the cell's metabolic activities and energy needs

Q: How many membranes do mitochondria have?

Mitochondria have two membranes: an outer membrane and an inner membrane

Q: What is the structure of the mitochondrial membranes?

Both membranes consist of a phospholipid bilayer with a unique collection of embedded proteins

Q: What are cristae in mitochondria?

Cristae are folds in the inner membrane that project into the matrix

Q: Why are cristae important?

Cristae maximize ATP output by increasing the surface area of the inner membrane

Q: What does the inner membrane enclose in mitochondria?

The inner membrane encloses a semifluid matrix containing mitochondrial DNA and ribosomes

Q: What is found in the mitochondrial matrix?

The matrix contains enzymes that break down carbohydrates and other nutrient molecules

Q: Why are mitochondria called the powerhouse of the cell?

Mitochondria convert the chemical energy of food into ATP during cellular respiration, using oxygen and releasing carbon dioxide