Plant

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Plant Animal Cells

• By Alyssa Meneen
• Biology 20
• Mar-April 2007

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Table Of Contents

• Pg 1-Introduction to Plant Animal Cells
• Pg 2-Table Of Contents
• Pg 3-Plant Animal Cells, and There Functions
• Pg 4-18-Plants Animals Cell Functions

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Plant Cell Animal Cell
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Nucleus

• The nucleus Is the most obvious organelle in
  the cell, It is enclosed in a double membrane and
  communicates with the surrounding cytosol via
  numerous nuclear pores.
• Within the cell is the DNA responsible for
  providing the cell with its unique
  characteristics. The DNA is similar in every cell
  of the body, but depending on the specific type,
  some genes may be turned on or off thats why a
  liver cell is different from a muscle cell, and a
  muscle cell is different from a fat cell.
• http//www.cellsalive.com/cells/cell_model.htm

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Nucleolus

• Within the nucleus are found chromatin and a
  structure called the nucleolus. Chromatin is DNA
  in its active form. It consists of DNA looped
  around histone proteins. The nucleolus is a knot
  of chromatin. It is the nucleolus that
  manufactures ribosomes.
• http//en.wikipedia.org/wiki/Nucleolus

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Ribosomes

• Ribosomes are packets of RNA and protein that
  play a crucial role in both prokaryotic and
  eukaryotic cells. They are the site of protein
  synthesis. Each ribosome comprises two parts, a
  large subunit and a small subunit. Messenger RNA
  from the cell nucleus is moved systematically
  along the ribosome where transfer RNA adds
  individual amino acid molecules to the
  lengthening protein chain.
• http//en.wikipedia.org/wiki/Ribosome

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Chloroplasts

• The chloroplast is a complex double membraned
  organelle that performs the function of
  photosynthesis within plant cells and contains
  the substance chlorophyll that is essential for
  this process. All reactions of photosynthesis
  occur in this organelle, and in addition, the
  chloroplasts also create sugar from the sun for
  the cell and make all the food for other
  organelles. The chloroplasts use photosynthetic
  chlorophyll pigment and take in sunlight, water
  and carbon dioxide to produce glucose and oxygen.
  This is the process of photosynthesis. The
  organelle takes in minerals found in the soil and
  air around them, and provides the cell with
  sunlight to make substances that the cell can
  process. An important structure in the
  chlorplasts is the inter-connected, flattened,
  membranous sacs called thylakoids. These
  structures are the site of the photosynthetic
  light reactions and it involves the transfer of
  electrons from a photo-excited state via the
  chlorophyll inside the thylakoids membrane to the
  stroma, which then produces ATP. In addition, the
  chloroplasts have their own DNA and ribosomes and
  reproduce by splitting in half, so basically,
  they are their own individual mini-cells. There
  are many chloroplasts in each cell to perform
  photosynthesis and its structure has two
  membranes. The outer membrane is eukaryotic in
  origin whereas, the inner membrane believed to be
  prokaryotic.
• http//sun.menloschool.org/cweaver
  /cells/c/chloroplast/

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Plants Cell Wall

• The cell wall performs a many of the most
  important functions in the cell overall . The
  cell wall provides the protoplast, or living
  cells,with mechanical protection and a chemically
  buffered environment. This function allows the
  cell to perform homeostatis upon itself, and live
  in a natural and contained environment. The cell
  wall is a wall that allows for the circulation
  and distribution of water, minerals, and other
  small nutrient molecules into and out of the
  cell. It provides rigid building blocks from
  which stable structures such as leaves and stems
  can be produced. This gives the cell a stable
  area and self contianed environment. Lastly it
  provides a storage site of regulatory molecules
  that sense the presence of pathogenic microbes
  and control the development of tissues within the
  cell. The cell wall in plants also helps to
  distinguish the plant cell from the animal cell.
• http//en.wikipedia.org/wiki/Cell_wall

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Central Vacuole

• The vacuole is where the water collects in the
  plant cells, as the water in the vacuole
  increases so does the pressure in the cell. And
  if water is not added to the plant, the pressure
  in the vacuole lessens, eventually causing the
  plant to wilt. The vacuole must work in
  conjunction with the cell membrane, both fro
  increasing/decreasing turgor pressure, and also
  with phagocytosis.
• http//sun.menloschool.org/cweaver/cells/c/vacuol
  e

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Mitochondria

• Mitochondria has two membranes, an inner and an
  outer membrane. The outer membrane is separated
  from the inner membrane by a liquid. The inner
  membrane then surrounds something known as the
  matrix.
• The inner membrane has enzymes in it so that it
  is able to break down nutrients. Like the small
  intestine, it has a lot of folds in it, called
  cristae, so it is able to break down more
  nutrients to turn into ATP. The process of
  turning these nutrients into ATP is known as
  respiration. Some of the respiration reactions
  happen in the matrix and some happen on the
  outside of the inner membrane which is covered in
  enzymes. Although the small intestine is used to
  break down a lot of the sugars into
  monosaccharides without the use of oxygen,
  Mitochondria is the only thing able to convert
  those sugars into ATP with oxygen. When using
  oxygen to break down monosaccharides, the
  efficiency of energy harnassed is multiplied to
  the 18.
• http//sun.menloschool.org/cweaver/cells/c/mitoch
  ondria/diagram.html

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Smooth Endoplasmic Reticulum

• The smooth ER is made up of a series of tubules
  and vesicles which branch and form a large
  network. Its functions in the plant are very
  similar to its functions in the body. This shape
  is very important to its functions. Because this
  organelle is smooth and has several folds, it
  expands to create a large amount of surface area.
  This surface area enables it to do the majority
  of its functions. The smooth ER is critical in
  the synthesis of lipids and membrane proteins as
  well. Another function of this organelle is to
  store and dispense calcium. The large surface
  area helps store calcium, then, as the smooth ER
  contracts, the calcium is released out of the
  cell. The smooth ER contributes to the health of
  the cell by interacting with and detoxifying
  toxic molecules as well. In animal cells, the
  smooth ER works with the mitochondria to make
  essential steroids. In plants, the smooth and
  rough sections of the ER make steroids needed on
  their own.
• http//cellbio.utmb.edu/cellbio/ser.htm

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Rough Endoplasmic Reticulum

• The function of the Rough Endoplasmic Reticulum
  is to synthesize and export proteins and
  glycoproteins. The rough Endoplasmic Reticulum is
  a series of connected vesicles and flattened
  sacs. It's function can best be studied in the
  secretory cells specialized in there function.
• The Rough Endoplasmic Reticulum is composed of
  one membrane, that membrane system is composed of
  the plasma membrane.
• http//sun.menloschool.org/birchler/cells/animals
  /rough_er/

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Golgi Apparatus

• The golgi apparatus is membrane-bound structure
  with a single membrane. It is actually a stack of
  membrane-bound of vesicles that are important for
  packaging macromolecules for transport elsewhere
  in the cell.
• The stack of larger vesicles I surrounded by
  numerous smaller vesicles containing those
  packaged macromolecules.
• http//www.cellsalive.com/cells/cell_model.htm

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Cell Membrane

• The purpose of the membrane is to control what
  goes in and out of the cell. The items that go in
  are highly regulated. It also communicates with
  other cells for example with receptors on the
  surface or cell to cell adhesion. Proteins that
  are found in the bilayer are receptor proteins,
  which deal with communication, recognition
  proteins and transport proteins that regulate the
  movement of water and soluble molecules through
  the membrane. In order to regulate the transport
  of molecules, there are two types of proteins in
  the cell carrier proteins and transport
  proteins.
• Basics from
• http//www.cellsalive.com/cells/cell_model.htm

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Vacuole

• Vacuoles are surrounded by membranes. They are
  sort of like a storage bubble in the cytoplasm.
  Vacuoles in animal cells are considerably smaller
  than those in plant cells. In animal cells
  vacuoles may store food that needs to be
  digested. Food cannot pass through membranes
  until it is broken into smaller particles. The
  lysosome can fuse with the vacuole membrane and
  squirt digestive enzymes into the food vacuole to
  break down what is in there. Your white blood
  cells do this when they eat invading bacteria.
  Vacuoles can also store the undigestible wastes
  until they can fuse with the cell membrane and
  squirt the wastes outside.Vacuoles in animal
  cells can form when the cell membrane surrounds a
  material and pinches off to bring the substance
  inside the cell. This process is called
  endocytosis.
• http//micro.magnet.fsu.edu/cells/plants/vacuole.h
  tml

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Plant Cell Vacuoles

• The cell sap vacuole in plants is much larger
  than animals. In addition to storing important
  substances, it also helps support the plant. The
  pressure of water filling the cell sap vacuole
  pushes out against the cell wall. This gives the
  wall enough strength to hold up fairly large gree
  (non-woody) plants. We all know the first
  indication that we are not giving our house
  plants enough water. They start to droop or wilt.
  Now you know why, so keep that cell sap vacuole
  filled with water.http//micro.magnet.fsu.edu/ce
  lls/plants/vacuole.html

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Centrosomes

• Centrosomes are often associated with the
  nuclear membrane during interphase of the cell
  cycle. In mitosis the nuclear membrane breaks
  down and the centrosome nucleated microtubules
  can interact with the chromosomes to build the
  mitotic spindle.
• The mother centriole, the one that was inherited
  from the mother cell, also has a central role in
  making cilia and flagella 1.
• The centrosome is duplicated only once per cell
  cycle so that each daughter cell inherits one
  centrosome, containing two centrioles. The
  centrosome replicates during the S phase of the
  cell cycle. During the prophase of mitosis, the
  centrosomes migrate to opposite poles of the
  cell. Mitotic spindle forms between the two
  centrosomes. Upon division, each daughter cell
  receives one centrosome. Aberrant numbers of
  centrosomes in a cell have been associated with
  cancer.
• Interestingly, centrosomes are not required for
  the progression of mitosis. When the centrosomes
  are irradiated by a laser, mitosis proceeds
  normally with a morphologically normal spindle.
  Moreover, development of the fruit fly Drosophila
  is largely normal when centrioles are absent due
  to a mutation in a gene required for their
  duplication 4. In the absence of the centrosome
  the microtubules of the spindle are focused by
  motors allowing the formation of a bipolar
  spindle. Many cells can completely undergo
  interphase without centrosomes.
• http//en.wikipedia.org/wiki/Centrosome

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Cytoskeleton

• The cytoskeleton is a cellular scaffolding or
  skeleton contained, as all other organelles,
  within the cytoplasm. It is contained in all
  eukaryotic cells and recent research has shown it
  can be present in prokaryotic cells too.1 It is
  a dynamic structure that maintains cell shape,
  and also has been known to protect the cell,
  enables some cell motion (using structures such
  as flagella and cilia), and plays important roles
  in both intra-cellular transport (the movement of
  vesicles and organelles, for example) and
  cellular division. It is a bone-like structure
  floating around within the cytoplasm.
• http//en.wikipedia.org/wiki/Cytoskeleton