NewWholeCh3- module 3

What are the two types of cells based on the presence of a nucleus?

Prokaryotic (no nucleus) and Eukaryotic (with nucleus).

What is cell theory?

All living organisms are made of cells and all cells come from preexisting cells.

How are cells typically measured?

Cells are usually measured in micrometers.

Why are cells generally small?

As cells grow larger, their surface area to volume ratio decreases, making it less efficient for materials to pass in and out.

What common features do all cells share?

A plasma membrane, chromosomes made of DNA, ribosomes, and cytoplasm.

What is the defining characteristic of prokaryotic cells?

Prokaryotic cells do not have a nucleus; their DNA is located in a nucleoid region.

What are plasmids?

Small rings of DNA found in some prokaryotes.

What do bacterial cell walls contain?

Peptidoglycan.

What are the key organelles found in eukaryotic cells?

Nucleus, ribosomes, endoplasmic reticulum, Golgi apparatus, lysosomes, mitochondria, and chloroplasts.

What is the role of the nucleus in a cell?

The nucleus directs cell activities and contains the instructions for making proteins.

What two types of ribosomes exist in cells?

Free ribosomes (in cytoplasm) and bound ribosomes (attached to the endoplasmic reticulum).

What is the main function of the rough endoplasmic reticulum (RER)?

To package and process proteins for secretion or organelles.

What is the function of smooth endoplasmic reticulum (SER)?

It is involved in lipid synthesis and detoxification, among other metabolic tasks.

What does the Golgi apparatus do?

It collects, sorts, packages, and distributes proteins and lipids.

What are lysosomes?

Membrane-bound sacs of digestive enzymes found in animal cells.

What is the primary role of mitochondria?

To carry out cellular respiration.

What process do chloroplasts perform?

Photosynthesis.

What is the basic structure of a chloroplast?

Double-membraned with interconnected thylakoids stacked into grana.

What is the cytoskeleton?

A network of protein fibers that support cell shape and organize cellular components.

What are centrioles?

Centriole structures found in animal cell centrosomes important for organizing spindle fibers during cell division.

What do cilia and flagella do?

They are extensions of the cell that produce movement; cilia are short and numerous, while flagella are long and few.

What composes plant cell walls?

Primarily polysaccharide cellulose.

What does the endosymbiotic theory propose?

That chloroplasts and mitochondria originated from engulfed prokaryotes and established a symbiotic relationship.

What evidence supports the endosymbiotic theory?

Mitochondria and chloroplasts have similarities to bacteria, such as size, double membranes, and their own DNA.

What is the role of the nucleolus?

It is responsible for manufacturing ribosomal RNA and assembling ribosomal subunits.

How do plant cells differ from animal cells?

Plant cells have cell walls, chloroplasts, and a large central vacuole, while animal cells have centrioles and lysosomes.

______ are the basic structural and functional units of life.

Cells.

The ______ is a selectively permeable barrier that surrounds a cell.

Plasma membrane.

Eukaryotic cells contain a ______, which houses the cell's genetic material.

Nucleus.

The ______ is responsible for producing energy in eukaryotic cells.

Mitochondria.

In plant cells, ______ are responsible for capturing sunlight for photosynthesis.

Chloroplasts.

Prokaryotic cells lack a defined ______.

Nucleus.

The ______ is a jelly-like substance inside the cell where organelles are suspended.

Cytoplasm.

Ribosomes are made of ribosomal RNA and ______.

Proteins.

The ______ provides structural support to plant cells.

Cell wall.

The ______ reticulum has ribosomes attached to it and is involved in protein synthesis.

Rough endoplasmic.