Cell Structures and Organelles: Microtubules, Cytoskeleton, and Photosynthesis

9+2 (microtubule) configuration

A specific arrangement of microtubules found in cilia and flagella, consisting of a ring of nine pairs of microtubules surrounding a central pair

Actin filaments

Thin, flexible protein fibers that are part of the cytoskeleton. They are involved in cell movement, muscle contraction, and maintaining cell shape.

Cellulose

A complex carbohydrate (polysaccharide) that is the main component of plant cell walls, providing structural support

Central vacuole

A large organelle found in mature plant cells that stores water, nutrients, and waste, and helps maintain turgor pressure.

Cilia

short, hair-like projections on the surface of some cells that move in a coordinated way to propel the cell or to move fluid over the cell's surface.

Circular DNA

A type of DNA that forms a closed loop, found in prokaryotes, mitochondria, and chloroplasts.

Chloroplasts

Organelles found in plant cells and algae that are the site of photosynthesis. They contain the green pigment chlorophyll.

Chromatin

The complex of DNA and proteins (histones) that forms chromosomes within the nucleus of eukaryotic cells.

Cytoskeleton

A network of protein filaments and tubules within the cytoplasm of a cell that provides structural support and is involved in cell movement and transport.

Electron microscope

A powerful microscope that uses a beam of electrons to create a magnified image of an object, allowing for much higher resolution than a light microscope

Endomembrane system

a group of membranes and organelles in eukaryotic cells that work together to modify, package, and transport lipids and proteins. It includes the ER, Golgi apparatus, and lysosomes.

Endoplasmic reticulum

A network of membranes within the cytoplasm of eukaryotic cells, involved in protein and lipid synthesis.

Eukaryotes

Organisms whose cells contain a nucleus and other membrane-bound organelles.

Extracellular matrix

A collection of molecules secreted by cells that provides structural and biochemical support to the surrounding cells

Flagella

Long, whip-like appendages on the surface of some cells that are used for movement.

Golgi apparatus

An organelle in eukaryotic cells that modifies, sorts, and packages proteins and lipids for secretion or delivery to other organelles.

Intermediate filaments

Cytoskeletal filaments that provide tensile strength and anchor organelles in place.

Light microscope

A microscope that uses visible light and a system of lenses to magnify images of small objects

Lysosomes

Small, membrane-bound organelles in animal cells that contain enzymes to break down waste materials, cellular debris, and foreign invaders

Magnification

The process of enlarging the apparent size of an object, typically using a microscope.

Microtubules

Hollow tubes made of the protein tubulin that are part of the cytoskeleton. They are involved in maintaining cell shape, organelle movement, and forming structures like cilia and flagella.

Mitochondria

these organelles are the site of cellular respiration, where ATP (the cell's energy currency) is produced.

Motor Proteins

Proteins that use energy to move along cytoskeletal filaments, transporting organelles and other cellular components.

Nucleus

the membrane-bound organelle in eukaryotic cells that contains the cell's genetic material (DNA).

Nucleolus

A dense structure within the nucleus where ribosomes are made

Organelle

specialized structure within a cell that performs a specific function.

Peroxisomes

Small, membrane-bound organelles that contain enzymes to break down various substances, including fatty acids and amino acids, and detoxify certain harmful compounds.

Prokaryotes

Single-celled organisms that lack a nucleus and other membrane-bound organelles.

Plasma membrane

The semipermeable membrane that encloses the cytoplasm of a cell, regulating what enters and leaves.

Smooth ER

he portion of the endoplasmic reticulum that lacks ribosomes. It is involved in lipid synthesis, detoxification, and calcium storage.

Resolution

The ability of a microscope to distinguish between two closely spaced objects as separate.

Rough ER

The portion of the endoplasmic reticulum with ribosomes attached to its surface. It is involved in the synthesis and modification of proteins.

Ribosome

A small, non-membrane-bound structure that is the site of protein synthesis.

Thylakoid

A flattened, sac-like membrane inside a chloroplast. They are arranged in stacks called grana and are the site of the light-dependent reactions of photosynthesis.

Vacuole

A membrane-bound sac that functions in storage and waste disposal. In plant cells, it is typically a large central vacuole; in animal cells, they are smaller and more numerous.

Vesicle

A small, membrane-enclosed sac that is used to transport materials within a cell.