Transcript Cell Organelles Section 7.2

CHAPTER 7
CELL STRUCTURE & FUNCTION
Biology I – 10/23/12
Turn in Vocab Terms
 Microscope Lab Day 1 w.s

7.2 Eukaryotic Cell Structure

Objectives:
 Describe
the function of the nucleus
 Describe the functions of the major cell organelles
 Identify the main roles of the cytoskeleton
7.2 Eukaryotic Cell Structure

Cell organization
Organelles



“little organs”
the specialized
structures within the
cell that perform a
function
Cytoplasm
 The
fluid that fills the entire cell
 The portion of the cell outside of the nucleus
 In
plants and animals
The Nucleus



“Control center” of the cell
Contains nearly all of the cell’s DNA &, with it, the
coded instructions for making proteins and other
important molecules
In plants and animals
Inside the Nucleus

Chromosomes
 Looks
like granular material
 Contain genetic information/DNA
Inside the Nucleus
Inside the Nucleus

Nucleolus


Small, dense area in
nucleus
Directs the formation of
ribosomes
Ribosomes



Small circles
Make proteins
Found in cytoplasm and
on ER
Rough ER-looks like continuous tubes
 Has
ribosomes on its surface
 Modifies proteins
 Produces proteins that will eventually leave the cell
Smooth ER
 No
ribosomes
 Has enzymes
 makes membrane lipids &
the detoxification of drugs
Golgi Apparatus



Looks like a stack of flat
pancakes
Proteins produced in the
rough ER move here
Modifies, sorts, & packages
materials from the ER
Lysosomes
The “clean-up crew”
 Small organelles filled with enzymes
 Break down cellular
materials

Lysosomes (cont)



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Found mostly in white blood cells
Have been linked to diseases, such as Tay Sach’s
Tay Sach’s is a disorder that is caused by a genetic
defect that prevents the formation of an essential
enzyme that breaks down lipids
These lipids build up in the body and can cause
nerve damage; prognosis is not good
Peroxisome



Look like lysosomes
Contains enzymes such as catalase
Hydrogen peroxide is broken down here
Vacuoles
Large sac-like, membrane
enclosed structures
Storage unit
Larger in plant cells


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
Pressure allows plants to
support heavy structures
Mitochondria


“Powerhouse” of the cell
Creates cellular energy (ATP)
for the cell to function
Chloroplasts

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
Capture energy from
the sun & convert it into
chemical energy –
photosynthesis!
Where photosynthesis
occurs
Only in plant cells
Cytoskeleton

helps cells keep its shape

The framework of the cell

Made up of microfilaments
and microtubules
Cytoskeleton