Eukaryotes PT 1

What domain do eukaryotic cells belong to?

Eukarya

What are the two domains of prokaryotes?

Bacteria and Archaea

Do eukaryotic cells have a nucleus?

Yes.

Do eukaryotic cells have membrane-bound organelles?

Yes.

Which type of cell is generally larger, prokaryotic or eukaryotic?

Eukaryotic.

Where is DNA located in eukaryotic cells?

Inside the nucleus.

How many chromosomes do eukaryotic cells typically have?

Multiple linear chromosomes.

What four structures do all cells contain?

Cytoplasm, plasma membrane, chromosomes, and ribosomes.

What organisms are eukaryotes?

Protozoa, algae, fungi, plants, and animals.

Can eukaryotes be unicellular?

Yes.

Can eukaryotes be multicellular?

Yes.

What are the four distinguishing characteristics of eukaryotic cells?

Nucleus, membrane-bound organelles, cytoskeleton, and multiple linear chromosomes.

What is the function of the nucleus?

Stores DNA and controls cellular activities.

Why is the nucleus called the control center of the cell?

It regulates gene expression and cell activities.

What surrounds the nucleus?

The nuclear envelope.

How many membranes make up the nuclear envelope?

Two.

What controls movement into and out of the nucleus?

Nuclear pores.

What is chromatin?

DNA wrapped around histone proteins.

What proteins help package DNA into chromatin?

Histones.

What are the functions of the nucleus?

DNA storage, replication, and transcription.

What is the nucleolus?

A dense region inside the nucleus where ribosomes are produced.

What is produced in the nucleolus?

rRNA and ribosomal subunits.

What is rRNA?

Ribosomal RNA.

What is the function of ribosomes?

Protein synthesis.

What size are eukaryotic ribosomes?

80S.

What size are mitochondrial and chloroplast ribosomes?

70S.

What are the two types of eukaryotic ribosomes?

Free ribosomes and membrane-bound ribosomes.

Where are free ribosomes located?

In the cytoplasm.

What do free ribosomes produce?

Proteins used inside the cell.

Where are membrane-bound ribosomes located?

On the rough endoplasmic reticulum.

What do membrane-bound ribosomes produce?

Proteins for secretion, membranes, or lysosomes.

What is the endomembrane system?

A network of membranes that transports materials throughout the cell.

Which organelles make up the endomembrane system?

Endoplasmic reticulum, Golgi apparatus, lysosomes, and vesicles.

Why is the endomembrane system important?

It transports materials too large to cross membranes directly.

What does ER stand for?

Endoplasmic reticulum.

What are the two types of endoplasmic reticulum?

Rough ER and Smooth ER.

Why is rough ER called "rough"?

It has ribosomes attached.

What is the primary function of rough ER?

Protein synthesis and transport.

What happens to proteins after they are made on the rough ER?

They are packaged into transport vesicles.

Where do transport vesicles carry proteins?

To the Golgi apparatus, plasma membrane, another organelle, or outside the cell.

What is a transport vesicle?

A membrane-bound sac that carries materials throughout the cell.

Does smooth ER have ribosomes?

No.

What are the functions of smooth ER?

Lipid synthesis, carbohydrate metabolism, and detoxification.

What is the structure of the Golgi apparatus?

A stack of flattened membrane sacs called cisternae.

What is the function of the Golgi apparatus?

Modifies, sorts, and packages proteins and lipids.

Which side of the Golgi receives vesicles?

Cis face.

Which side of the Golgi ships vesicles out?

Trans face.

What are secretory vesicles?

Vesicles that carry proteins out of the cell.

What is exocytosis?

The release of materials from the cell by vesicles fusing with the plasma membrane.

What are lysosomes?

Membrane-bound sacs containing digestive enzymes.

What is the primary function of lysosomes?

Digest worn-out organelles, food, microbes, and cellular debris.

Which organelle forms lysosomes?

Golgi apparatus.

What are peroxisomes?

Membrane-bound organelles involved in oxidation reactions.

Are peroxisomes part of the endomembrane system?

No.

What harmful substance is produced in peroxisomes?

Hydrogen peroxide.

Which enzyme breaks down hydrogen peroxide?

Catalase.

What are the functions of peroxisomes?

Fatty acid breakdown, detoxification, and protection from oxidative damage.

What is the cytoskeleton?

A network of protein fibers that supports the cell.

What are the three components of the cytoskeleton?

Microfilaments, intermediate filaments, and microtubules.

What are microfilaments made of?

Actin.

What are the functions of microfilaments?

Cell movement, muscle contraction, cytokinesis, and cytoplasmic streaming.

What are intermediate filaments made of?

Fibrous proteins.

What is the function of intermediate filaments?

Maintain cell shape and anchor organelles.

What are microtubules made of?

Tubulin.

What are the functions of microtubules?

Intracellular transport, chromosome movement, and support for cilia and flagella.