2.1 Cells
-
Upload
melinda-macdonald -
Category
Documents
-
view
389 -
download
0
Transcript of 2.1 Cells
Cells
cell structure
Common Cell Traits
Cell membrane•outer covering of cell•made of one or more layers of linked molecules
Cytoplasm•inside every cell•gelatin-like•contains hereditary material that controls the life of the cell
comparing cells
nerve cells can be 1m long
human egg cell is no bigger than the dot on this i
human red blood cells is 1/10 the size of a human egg cell
bacterium are even smaller- 8000 can fit inside a human egg cell
cell types
PROKARYOTIC CELLSno membrane bound
structures
EUKARYOTIC CELLSmembrane-bound
structures
Cell Organization
cell wall
found in plants, algae, fungi, most bacteria
tough, rigid outer coverings that protect the cell and give
it shapeplant cell walls
are mainly made of
cellulose....which is?
what makes the cell walls rigid? Pectin and
lignin!
cell membrane
protective layer around all cellsif a cell has a cell wall, then
the cell membrane is
inside of it
what does it do? regulate interactions between the cell and the environment
water can move into and out of cell through the cell membrane
food particles and some molecules enter and waste products leave
through the cell membrane
cytoplasm
gelatinlike substance that fills cells which is constantly moving
contains a framework called the
cytoskeleton - this helps
maintain or change the
shape of the cell
cytoskeleton helps some cells move
cytoskeleton is made up of thin, hollow tubes of protein and thin, solid protein
fibers
organelles
contained within the cytoplasm
What do organelles do? ★process energy★manufacture substances needed by the cell★move materials★act as storage sites★are surrounded by membranes★nucleus is usually the largest organelle
nucleus
is surrounded by a membrane
directs all cell activities
DELI MANAGER
materials enter and leave through the membrane
contains
instructions for
everything in the
cell, which are
found on DNA
a nucleolus is also within the nucleus
energy-processing organelles
cells need energy to: ✤process food✤make new substances✤eliminate wastes✤communicate with each other
PLANTS๏food is made in green organelles called chloroplasts๏contain green pigment chlorophyll๏chlorophyll captures light energy that is used to make glucose
ANIMALS๏energy in food is stored until it is released by the mitochondria๏organelles where energy is released from the breakdown of food into carbon dioxide and water๏muscle cells are more active, so they contain more mitochondria
manufacturing organelles
proteins take part in nearly every cell activity
Proteins: •part of cell membrane•needed for chemical reactions that take place in the cytoplasm•are produced on small structures called ribosomes
ribosomes
considered an
organelle, but they do
not have a membrane
some float freely in cytoplasm, some attach to the endoplasmic reticulummade in the
nucleolus
receive directions from DNA on how,
when, and in what
order to make specific proteins
processing, transporting, and storing organelles
endoplasmic reticulum (ER) extends from the nucleus to the cell
membrane
a series of folded membranes
materials can be processed and moved around
inside of the cell
rough vs.
smooth
smooth ER process pther cellular substances such as lipids that sore energy
Rough ER make proteins that are
moved out of the cell or used within the cell
rough vs.
smooth
golgi bodies proteins are made and sent
to the Golgi
bodies
Golgi bodies sort proteins and other cellular substances and
package them into membrane-bound structures called vesicles
vesicles deliver cellular substances to areas inside the cell
Refrigerator - cells have membrane-bound spaces called vacuoles for temporary
storage of materials (water, waste products, food, and other cellular
materials)
recycling organellesactive cells break down and recycle
substances
lysosomes contain digestive chemicals
that help break down food
molecules, cell wastes, and worn-
out parts
lysosome membrane keeps the chemicals from leaking into the
cellwhen a cell dies a lysosome’s membrane
disintegrates, releasing digestive chemicals that quickly breakdown the
cell’s contents
organ system
tissue
cell
Plant Cell Video
Animal Cell Video
Plant and AnimalVideo