CK-12 Biology Interactive Edition Chapter 3

cytoskeleton

helps cell keep its shape and holds organelles in place (crisscrosses through cytoplasm); found in prokaryotic cells (bacteria); three-dimension structure and acts as muscles and a skeleton

viruses

are not cells (contain DNA)

cells

basic unit of structure and function of all living things

why do cells have so much surface area?

because then they can absorb more

eukaryote cells

contain nucleus; larger than a prokaryotic and fungi

chloroplasts

contains cells pigment; captures light from sun and makes energy

Robert Hooke

discovered cells and named them; looked through microscope

molecules of cholesterol

help membrane keep its shape

molecules requirements to pass through cell

hydrophilic (loves water)- can't pass through membrane hydrophobic (hates water)- passes through membrane easily

nucleus

in the cytoplasm, is surrounded by a membrane, contains DNA, the "heart" of the cell

golgi apparatus

large organelle that processes proteins and prepares them for both inside and outside the cell; moves lipids around; post office of the cell

ATP (adenosine triphosphate)

molecule that carries energy

smooth endoplasmic reticulum

organelle that isn't studded with ribosomes (makes lipids)

mitochondria

organelle that makes energy

endoplasmic reticulum (ER)

organelle that transports proteins and lipids (studded with ribosomes)

centrioles

organelles involved in cell division; organize chromosomes before cell division; only found in animal cells

what common parts do all cells have?

plasma membrane, cytoplasm, ribosomes, and DNA

endosymbiotic theory

prokaryotes where engulfed by bigger prokaryote cells and the cells evolved

vacuoles

sac-like organelles that store and transport materials in the cells

central vacuole

stores substances (water, enzymes, and salt); helps plant tissue

organelle

structure in the cytoplasm

cell wall

surrounds plasma membrane; supports and protects cell

cytoplasm functions

suspending cell organelles, pushes agains plasma membrane to help cell keep its shape; provides site for biochemical reactions of cell; the squishy stuff in cells

vesicles

they are vacuoles that have biochemical reactions; lysosomes-break down dead cells and foreign matter; peroxisomes- use oxygen to break down poisons

phospholipid bilayer

two layers make up plasma membrane; made up of fatty acids and alcohol; The legs hate water and the heads love water

plasma membrane

(cell membrane) thin coat of lipids surrounding a cell (a protective wall between the outside and inside enviorment)

selective permeability

ability to allow only certain molecules in or out of the cell

cell theory

all organisms are made of one or more cell; life functions occur in cells; cells come from existing cells

ribosome

where proteins are made (in cytoplasm) and assembles amino acids in the polypeptides