Chapter 4 Vocabulary
Cell
The smallest functional and structural
unit of all living organisms; usually
consists of a nucleus, cytoplasm, and a
membrane
Cell Membrane
 A (phospholipid)
layer that covers a cell’s
surface and acts as a barrier between the
inside of a cell and the cell’s environment
Organelle
 One
of the smallest bodies in a cell’s
cytoplasm that are specialized to perform
a specific function
Nucleus
 In
a eukaryotic cell, a membranebound organelle that contains the
cell’s DNA and that has a role in
processes such as growth,
metabolism, and reproduction
 “The Boss”
Prokaryote
A single-celled organism that does not
have a nucleus or membrane bound
organelles; examples are archaea and
bacteria.
“Pro” = before; karyon = kernel or nut
Eurkaryote
 An
organism made up of cells that have a
nucleus enclosed by a membrane;
eukaryotes include protists, animals,
plants, and fungi but archaea or bacteria.
 “eu” = good or true
Cell Wall
 A rigid
structure that surrounds the cell
membrane and provides support to the cell
lysosome
digestive enzymes – are
responsible for digesting inside a cell;
Found mainly in animal cells . They
destroy worn-out or damaged organelles,
get rid of waste materials and “swallow”
foreign invaders.
 “Trash Collectors”
 contain
mitochondrion
 organelle
that breaks down food
molecules to release energy in a
substance called ATP (where energy is
stored). It’s the power source of a cell
 “Power Plant”
cytoskeleton
 The
cytoplasmic network of protein
filaments that plays an essential role in cell
movement, shape and division (mitosis)
Golgi complex
 Organelle
that helps make and package
materials to be transported out of the cell
 “Shipping & Handling”
Endoplasmic reticulum
 (ER)
a system of membranes that is
found in a cell’s cytoplasm and that assists
in the production, processing and transport
of proteins and in the production of lipids
 “Highway”
chloroplast
 An
organelle found in plant and algae cells
where photosynthesis occurs
ribosome
 A cell
organelle composed of RNA* and
protein; site of protein synthesis (makes
protein by assembling chains of amino
acids)
 Smallest organelles

*extra: RNA transfers info from DNA
vesicle
 A small
cavity or sac that contains
materials in an eukaryotic cell
organism
 A living
thing; anything that can carry out
life processes independently
function
 The
special, normal or proper activity of an
organ or part (what it does)
structure
 The
arrangement of parts in an organism
(how it’s made)
tissue
 A group
of similar cells that perform a
common function
organ
 A collection
of tissues that carry out a
specialized function of the body
Organ system
 A group
of organs that work together to
perform body functions (example:
cardiovascular system)