Download science words chapter 3

Words to Know
about Cells and
the Parts of the
Cells
Key words
Cell
sel
A membrane-covered
structure that contains all of
the materials necessary for life
Homeostasis
hO-mE-O-'stA-s&s
The maintenance of a stable
internal environment
Unicellular
yü-ni-'sel-y&-l&r
Organisms made from
a single cell
Multicellular
Organims made of
many cells
Prokaryotic
prO-'ka-rE-"Ot/
Describes a cell that does not have
a nucleus or any other
membrane-covered organelles;
example: bacteria
Eukaryotic
yü-'ker-E-"Ot,
Describes a cell that has a
nucleus; examples: animals
and plants
The Chemistry of
Cells
Metabolism
m&-'ta-b&-"li-z&m
The combined chemical
processes that occur in a cell
or living organism
DNA
DeoxyriboNucleic Acid;
hereditary material that controls
all the activities of a cell, contains
the information to make new
cells, and provides instructions for
making proteins
ATP
Adenosine TriPhosphate;
molecule that provides
energy for a cell’s
activities
Nucleic acid
nu-'klE-ik-
A biochemical that stores
information needed to
build proteins and other
nucleic acids; made up of
subunits called nucleotides
Protein
'prO-"tEn
A biochemical
that is composed
of amino acids; its functions
include regulating chemical
reactions, transporting and
storing materials, and providing
support
Carbohydrate
•
A biochemical composed
of one or more simple
sugars bonded together
that is used as a source of
energy and to store
energy.
Lipid
A type of biochemical that
does not dissolve in water,
including fats and oils;
lipids store energy and
make up cell membranes.
Phospholipid
A molecule that forms
much of a cell
membrane
Chlorophyll
The green chemical
pigment in chloroplasts
that absorbs light
energy for
photosynthesis
Organelles
Organelle
•Structures within a
cell, sometimes
surrounded by a
membrane
Cytoplasm
•Cellular fluid
surrounding a
cell’s organelles
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
Nucleus
• Membrane-covered
organelle found in
eukaryotic cells that
contains a cell’s DNA
and serves as a control
center for the cell
Mitochondria
• Cell organelles
surrounded by two
membranes that break
down food molecules to
make ATP
Ribosome
•A small organelle
in cells where
proteins are made
from amino acids
Endoplasmic reticulum
• A membrane-covered
cell organelle that
produces lipids, breaks
down drugs and other
substances, and
packages proteins for
delivery out of the cell
Golgi complex
• The cell organelle
that modifies,
packages, and
transports materials
out of the cell
Vacuole
• A large membranecovered structure found in
plant cells that serve as
storage containers for
water and other liquids;
animal cells have small
vacuole.
Lysosome
• A special vesicle in
cells that digest food
particles, wastes and
foreign invaders
Vesicle
• A membrane-covered
compartment in a
eukaryotic cell that forms
when part of the cell
membrane surrounds an
object and pinches off.
Plant
organelles
Cell wall
• A structure that
surrounds the cell
membrane of some cells
and provides strength and
support to the cell
membrane; found in
plants, and fungi
Chloroplast•
An organelle found
in plant and algae
cells where
photosynthesis
occurs