Unit 2 Concept 1🧬✅

Science

Unicellular

An organism composed of only one single cell.

Multicellular

An organism composed of many cells

Cell Theory

Al living things are made of cells, cells are the basic unit of life, and all cells come from other cells.

Prokaryotic Cell

Cell type lacking a nucleus and membrane-bound organelles, dividing by binary fission, and found in bacteria with peptidoglycan cell walls.

Eukaryotic Cell

Cell type containing a nucleus and membrane-bound organelles, dividing by mitosis, and found in animals, plants, fungi, and protists.

Organelles

Specialized structures within a cell that work together to help the cell function, primarily focused on making proteins.

Cell Membrane

Structure made of a phospholipid bilayer surrounding the outside of all cells that controls what goes in and out.

Hydrophilic

Property of water-loving molecules, such as the polar phosphate heads of cell membrane phospholipids.

Hydrophobic

Property of water-fearing molecules, such as the nonpolar fatty acid tails of cell membrane phospholipids.

Fluid Mosaic Model

Structural model of the cell membrane, which is composed of many freely moving parts including phospholipids, proteins, and carbohydrates.

Cytoskeleton

Threadlike protein fibers that give the cell shape, move organelles around, and provide structural support for animal cells.

Cytoplasm

Jelly-like fluid substance mainly composed of water that holds cell organelles in place.

Nucleus

Organelle surrounded by a nuclear envelope with pores that contains genetic material (DNA) and protects the DNA controlling cell activities.

Nucleolus

Structure located inside the nucleus responsible for making rRNA, which builds ribosomes.

Ribosomes

Structures composed of proteins and rRNA located on the Rough ER and floating in the cytoplasm that manufacture proteins.

Rough ER

Organelle hugging the nucleus with ribosomes on its surface that synthesizes proteins and packages them for secretion.

Smooth ER

Organelle attached to Rough ER lacking surface ribosomes that synthesizes membrane lipids.

Golgi Apparatus

Folded membrane organelle that receives protein vesicles from the ER to process, sort, and ship proteins throughout or out of the cell.

Vesicles

Mini transport carts within the cell that move proteins to required destinations.

Lysosomes

Enzyme-containing organelles found in animal cells that break down dead materials and facilitate programmed cell death (apoptosis).

Vacuoles

Storage organelles for water, nutrients, and waste that are small and numerous in animal cells.

Centrioles

Microtubule structures in animal cells (two together form a centrosome) that appear during cell division to pull chromosomes apart.

Cilia

Short, numerous cell surface projections that move fluid across the cell's surface.

Flagella

Long, few (1-3) whip-like projections that move the entire cell through extracellular fluid.

Microvilli

Short, numerous cell projections similar to cilia that remain stationary.

Mitochondria

Known as the powerhouse of the cell, consisting of an inner membrane and matrix where cellular respiration occurs to release energy as ATP.

Chloroplast

Plant cell organelle consisting of grana stacks and fluid stroma where photosynthesis converts sunlight into sugar energy.

Cell Wall

Protective structure outside the plasma membrane in plant, fungal, and bacterial cells that maintains cell shape.

Central Vacuole

A single massive central storage center organelle found exclusively in plant cells.