Cell Organelles Section 7.3
Cell OrganellesSection 7.3
Cell Wall
Found outside some cell membranes It provides support and protection Made of cellulose
Cell Membrane
Controls what enters and leaves the cell Made of lipids and proteins
Nucleus
Leader of the eukaryotic cell because it contains DNA
Every part of the cell depends on proteins to do its jobs, so by containing the blueprint to make proteins, the nucleus controls the activities of all the organelles
Chromatin
Strands of genetic material spread around the inside of the nucleus
Ribosomes and the Nucleolus
Ribosomes are created inside the nucleolus.
In order for proteins to be made, ribosomes must move from the nucleus to the cytopasm.
Cytoplasm
Fluid filled area within the cell Site of chemical reactions
Nuclear envelope The membrane
surrounding all the nuclear material.
Nucleoplasm-the fluid within the nucleus
Nuclear pores in the envelope allow materials to pass into and out of the nucleus
Endoplasmic Reticulum A transport network of
tubes and channels Sites of chemical
reactions Rough ER- has
ribosomes attached to the tubes
Folded Membranes Folded membranes
add surface area for reactions to take place.
The mitochondria and the chloroplast have many folded membranes
Ribosomes
Ribosomes are the sites for protein synthesis.
Golgi Apparatus
Structure that modifies and packages proteins
Made from pieces of the ER
Vacuoles
Temporary storage sites for food, water, and waste
Very large in the plant cell for water storage and turgor pressure
Lysosomes Membrane bound
structure that contains digestive enzymes.
Lysosomes in a tadpoles tail release their enzymes and destroy the tail cells, so the tail recedes
Processes the need Energy
Reproduction Movement Transportation Digestion Protein production Protein modification
Chloroplast Converts the sun’s
energy into chemical energy during photosynthesis
Plastids
Store pigments and starches in plant cells
Chloroplast- stores chlorophyll (green)
Chromoplast- stores other pigments
Leukoplast-stores starches
leukoplasts
chromoplasts
Mitochondria Releases energy from
food during the process of CELLULAR RESPIRATION
Cytoskeleton Thin, fibrous elements that provide
support for organelles Microtubules- thin, hollow cylinders
made of protein Microfilments - thin, solid protein
fibers
Cytoskeleton
Cilia and Flagella Cilia- tiny hair-like projections used in cell
movement Flagella- whip-like or tail-like appendage
used in cell movement
Prokaryote vs. Eukaryote Prokaryote Have cell wall Have cell membrane Have ribosomes Have a circular chromosome Ex: bacteria
Eukaryote Well defined nucleus Have membrane bound organelles DNA in the form of chromatin or
chromosomes Some have a cell wall Ex: plants, fungi, animals, protists
Eukaryote
Prokaryote
Plants vs. Animals
Plant Contain plastids Have a cell wall Have a large vacuole No centrioles
Animal No plastids No cell wall Small vacuoles Have centrioles that function during cell
division
Cell division in Ascaris megalocephala bivalens, in high optical enlargement, 1901.