Cell_Organelles

Question

Answer

What are the two main types of cells?

Prokaryotic cells and eukaryotic cells.

What structures do all cells have in common?

Cell membrane cytoplasm DNA and ribosomes.

What are organelles?

Specialized structures inside cells that perform specific functions necessary for cell survival.

Why are organelles important in eukaryotic cells?

They divide the cell into compartments so multiple chemical reactions can occur at the same time.

What major functions do organelles perform?

Transport energy production reproduction growth waste disposal and packaging of molecules.

Why do many organelles contain folded membranes?

Folded membranes increase surface area where chemical reactions can occur.

Why do cells have size limits?

As cells grow larger it becomes harder to transport materials across the membrane efficiently.

What is the cytoplasm?

A jelly-like solution inside the cell between the cell membrane and the nucleus where organelles are located.

What is cytosol?

The water-based fluid portion of the cytoplasm containing ions proteins glucose salts and other molecules.

What is the cytoskeleton?

A network of protein fibers that provides structure shape support and organization for the cell.

What are the three main parts of the cytoskeleton?

Microtubules intermediate filaments and microfilaments.

What do microtubules do?

They help move organelles within the cell and assist in cell division.

What do intermediate filaments do?

They anchor organelles and form internal scaffolding for the nucleus.

What do microfilaments do?

They help with muscle contraction and assist in cell division.

What is the function of the cell membrane?

It protects the cell controls what enters and exits the cell and keeps the cell contents together.

What does selectively permeable mean?

The membrane allows some substances to pass through while blocking others.

What is the nucleus?

The control center of the cell that contains and protects the cell's DNA.

What does the nucleus control?

Cellular activities such as metabolism protein synthesis growth and reproduction.

What is chromatin?

Uncoiled DNA found in the nucleus when the cell is not preparing to divide.

What are chromosomes?

Coiled DNA structures formed when the cell prepares for division.

What is the nuclear membrane?

A double membrane surrounding the nucleus that separates it from the cytoplasm.

What are nuclear pores?

Openings in the nuclear membrane that allow molecules like RNA and ribosomal subunits to move in and out of the nucleus.

What is the nucleolus?

A structure inside the nucleus where ribosomes are produced.

What happens to ribosomes after they are made?

They exit the nucleus through nuclear pores and help synthesize proteins.

What is the endoplasmic reticulum (ER)?

A network of membrane channels and sacs called cisternae that help produce and transport molecules.

What are the two types of endoplasmic reticulum?

Rough ER and Smooth ER.

Why is rough ER called rough?

Because ribosomes are attached to its surface.

What is the function of rough ER?

It synthesizes proteins and transports them to the Golgi apparatus.

How are proteins moved from the rough ER to the Golgi?

They are transported in membrane-bound vesicles.

What is the function of smooth ER?

It synthesizes lipids metabolizes carbohydrates and detoxifies drugs alcohol and toxins.

Why is smooth ER important for the cell membrane?

Because it produces lipids that are major components of membranes.

What are ribosomes?

Structures made of RNA and proteins that synthesize proteins.

Are ribosomes membrane-bound?

No ribosomes are not membrane-bound organelles.

Where can ribosomes be found?

Floating freely in the cytoplasm or attached to the rough ER.

What are the two ribosome subunits?

The large 60S subunit and the small 40S subunit.

What is the Golgi apparatus?

A stack of curved membrane sacs that modifies sorts and packages proteins and lipids.

What happens to proteins in the Golgi apparatus?

They may be modified by adding molecules like sugars and then packaged into vesicles.

Where do many Golgi vesicles go?

They transport molecules to other parts of the cell or outside the cell.

What organelles does the Golgi apparatus produce?

Lysosomes.

What is the endomembrane system?

A network of membranes that includes the ER Golgi apparatus lysosomes vesicles and the cell membrane working together to process and transport molecules.

What are vesicles?

Small membrane-bound sacs that transport substances within the cell or to the cell membrane.

What are vacuoles?

Membrane-bound sacs used for storage of materials such as water nutrients or waste.

How do vacuoles differ between plant and animal cells?

Animal cells have many small temporary vacuoles while plant cells have one large central vacuole.

What is the function of the large central vacuole in plant cells?

It stores water and maintains cell pressure to support the plant structure.

What are mitochondria?

Organelles where aerobic cellular respiration occurs to produce ATP.

What is cellular respiration?

The process that converts energy from glucose into ATP for cellular use.

What is ATP?

Adenosine triphosphate the main energy molecule used by cells.

Why is ATP called the energy currency of the cell?

Because it provides energy for cellular activities like movement protein synthesis and transport.

What are the two membranes of mitochondria?

An outer membrane and a highly folded inner membrane.

What are cristae?

Folded structures of the inner mitochondrial membrane that increase surface area for ATP production.

Why is increased surface area important in mitochondria?

It allows more chemical reactions to occur for ATP production.

What are plastids?

Plant cell organelles involved in storage and synthesis of important molecules.

What is a chloroplast?

A plastid found in plant cells that carries out photosynthesis.

What pigment is found in chloroplasts?

Chlorophyll.

What does chlorophyll do?

It absorbs light energy for photosynthesis.

What is photosynthesis?

The process plants use to convert light energy carbon dioxide and water into glucose and oxygen.

What unique feature do chloroplasts and mitochondria share?

Both contain their own DNA.

What are lysosomes?

Membrane-bound organelles containing digestive enzymes.

What is the function of lysosomes?

They break down waste molecules damaged organelles and foreign materials.

What processes do lysosomes help with?

Intracellular digestion recycling molecules defense and cell development processes like metamorphosis.

Why do lysosomes have thick membranes?

To prevent digestive enzymes from leaking and damaging the cell.