plant cell topic # 2013 by: leyna dussel
Post on 21-Dec-2015
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TRANSCRIPT
The Nucleus and Nucleolus The nucleus is the
most obvious organelle in any eukaryotic cell. It is a membrane-bound organelle and is surrounded by a double membrane. It communicates with the surrounding cytosol via numerous nuclear pores.
The Nucleus and Nucleolus Within the nucleus is the DNA responsible
for providing the cell with its unique characteristics.
The prominent structure in the nucleus is the nucleolus.
The nucleolus produces ribosomes, which move out of the nucleus to positions on the rough endoplasmic reticulum where they are critical in protein synthesis.
Endoplasmic Reticulum responsible for
the production of hormones and other secretor products
ER for short continuation of
the outer nuclear membrane
Smooth Vs. Rough ER The rough ER appears rough due to the
presence of ribosomes on the membrane surface
Rough ER is important in the synthesis of other proteins.
At the ribosomes on the rough ER, the messenger RNA is translated into proteins
Smooth ER is important in the synthesis of lipids and membrane proteins
Centrosome The centrosome, also called the
"microtubule organizing center", is an area in the cell where microtubles are produced
from each centrosome, microtubules grow into a "spindle" which is responsible for separating replicated chromosomes into the two daughter cells
Plant cells have centrosomes, but they do not have centrioles
Cytoskeleton primary importance
of the cytoskeleton is in cell motility
The internal movement of cell organelles
The cytoskeleton is an organized network of three primary protein filaments: microtubules, actin filaments, and intermediate fibers
Golgi Apparatus a stack of membrane-
bound vesicles that are important in packaging macromolecules (enzymatic or hormonal contents of lysosomes, peroxisomes and secretory vesicles) transport elsewhere in the cell
Mitochondria provide the energy a
cell needs membrane-bound
organelles, and like the nucleus have a double membrane
Combine sugar and oxygen to make ATP - the primary energy source for the cell
Vacuole membrane-bound sac that
plays roles in intracellular digestion and the release of cellular waste products
Vacuoles tend to be large in plant cells and play a role in turgor pressure. When a plant is well-watered, water collects in cell vacuoles producing rigidity in the plant. Without sufficient water, pressure in the vacuole is reduced and the plant wilts
Cell Membrane The membrane is a
double layer of lipids The membrane is
responsible for the controlled entry and exit of ions like sodium (Na) potassium (K), calcium (Ca++).
Cytosol The cytosol (cytoplasm) is the "soup"
within which all the other cell organelles reside and where most of the cellular metabolism occurs
full of proteins that control cell metabolism including signal transduction pathways, glycolysis, intracellular receptors, and transcription factors.
Cell wall Prokaryotic cells and
plant cells Only made up of
polysaccharides The cell wall provides
and maintains the shape of these cells and serves as a protective barrier