Transcript Cells the Basic Units of Life

Cells the Basic
Units of Life
1-2
Eukaryotic Cells
Essential Questions/Learning
Goals:


Identify the different parts of a
eukaryotic cell
Explain the function of each type of
organelle in a given eukaryotic cell.
Science Terms
 Cell
Wall
 Mitochondrion
 Endoplasmic Reticulum
 Ribosome
 Golgi Complex
 vesicle
 Lysosome
What organelles do plant and
animal cells have in common?
 Nucleus
 Ribosomes
 Cell
membrane
 Cytoplasm
What organelles are different
between plant and animal
cells?
 Plants


have …
A cell wall
chloroplasts
Cell Wall
 Do

all eukaryotes have a cell wall?
No. Only plants and fungi have a cell wall.
 What

is the function of the cell wall?
The cell wall provides a strong outer layer that
allows plants to stand upright and grow very tall.
(sequoia trees).
 Does
the cell wall need anything to keep it
strong?

Yes. The cell wall needs water!
Cell wall continued
 How
are the cell walls of fungi different
from the cell walls of plants?


The cell wall in plants is made of cellulose.
The cell wall in fungi is made of chitin.
Cell Membrane
 Do

all organisms have a cell membrane?
YES!!!!
 What
is the purpose of the cell
membrane?

To provide a barrier between the inside of
the cell and the outside environment.
 What

is it made of?
It is made of a double layer of “fats”.
How do nutrients and wastes
get through the membrane?
The
membrane has pores or
small openings that allow
small particles to enter or
leave.
Larger nutrients and wastes
need to go through special
protein passageways.
Cytoskeleton
 What


It is a web of proteins found throughout the
cytoplasm of the cell.
The word means “cell skeleton”.
 What


is it?
is its purpose?
To support the cell (keep it from collapsing)
To help with movement in some cells.
Nucleus
 What

It is the control center for the cell (like a
brain)
 What

kinds of cells have a nucleus?
Just eukaryotes!
 What

is it?
does it contain within it?
DNA
DNA
 What
 DNA
is the purpose of DNA?
contains all of the instructions for
making stuff the cell needs and directions for
reproduction.
Inside the Nucleus
 Does

the Nucleus have a membrane?
Yes a double layered membrane
 What’s

inside the nucleus?
The nucleolus (little nucleus)
What does the Nucleolus Do?
 We’re
not sure, but we think that
ribosomes are made here.
 How do the ribosomes get out of the
nucleolus and nucleus to enter the
cytoplasm?

The ribosomes travel from the nucleus to the
rest of the cell through pores or small
openings in the nuclear membrane.
Ribosomes
 Ribo
= colored and Some = body
 Do they have a membrane?

No!
 What

They make proteins from smaller pieces called
amino acids.
 Do

do they do for the cell?
cells have many ribosomes?
Yes, ribosomes are the most numerous organelles in
a cell.
Where in a cell can you find
Ribosomes?
 Some
are found floating in the cytoplasm
 Some are found attached to membranes.

They make the endoplasmic reticulum into
rough endoplasmic reticulum.
Endoplasmic Reticulum (ER)
 Endo

means:
Within
 Plasmic

means:
Fluid
 Reticulum

means:
Passageways or tubes
 Fluid
Filled (within) Passageways.
What is the purpose of the ER?
 They
are like
highways,
roads, or
hallways for
moving things
within a cell.
Endoplasmic Reticulum
Two Types of ER
 Smooth

ER:
No Ribosomes (it looks smooth)
 Makes
lipids (fats)
 Breaks down toxic materials
 Rough


ER:
Has ribosomes all along its length (looks rough)
Purpose:
 Makes
proteins (because of the ribosomes!)
 Found closer to the nucleus
Mitochondria
 Purpose:

“Powerhouse” for the cell.
 Provides

the cell with energy.
How does it do this?
 It
breaks sugar into an energy molecule
called ATP
 Do

all cells have mitochondria?
No, but most do.
Mito’s continued
 What

Mitochondria have their own DNA that is different
from the rest of the cell.
 What

is “odd” about DNA and Mitochondria?
could this mean?
It has been theorized that mitochondria were once
separate organisms that “fused” into another cell in a
symbiotic relationship (mutualism!)
Chloroplasts
 Purpose:

Make food for cell from light.
 What

kinds of cells have them?
Plant cells. (green parts only!)
 What
is the name of the process that
allows chloroplasts to make food from
light?

Photosynthesis
Chloroplast
Golgi Complex
 Purpose:

Food Storage (like a grocery store)
 Packages
 Looks


and stores proteins for the cell
like:
The Smooth ER, except the passages are
closed off.
A stack of pancakes.
Golgi Complex
Cell Compartments
 Vesicles:


Carry things around the cell
Can even bring things to be dumped
outside of the cell.
Cellular Digestion
 Lysosomes:


Contain enzymes that break down wastes and
other bad things. (think of Lysol!)
Found mostly in animal cells
 Vacuoles:



Usually store water
Can store enzymes too.
Found mostly in plants cells.
 Helps
keep the cell strong too (full vacuole keeps the
cell more rigid