PLant Cell Structure and Functions

• A cell is the smallest unit that can carry on all of the processes of life.
• Anton Van Leeuwenhoek is given credit for developing the first mini microscope and looking at pond water, making detailed drawings.
• Robert Hooke coined the term “cell” when he looked at slices of cork and dead plant cells.
• Nucleoplasm is the granular fluid inside the nucleus.
• Nucleolus is the site of synthesis of ribosomal RNA.
• Nuclear envelope is the outermost covering of the nucleus, composed of membrane perforated by numerous pores.
• Chromatin are darkly staining bodies inside the nucleus, containing genes.
• Robert Brown observed a dark structure near the center of the cell, which is now known as the nucleus.
• Rudolph Virchow stated that all cells come from the division of preexisting cells.
• The Cell Theory states that all living things are composed of cells, cells are the basic units of structure and function in living things, and all cells come from pre-existing cells.
• The size that most cells are able to obtain is limited by the relationship of the cell’s outer surface area to its volume, with most cells ranging from 10 - 100μm.
• Prokaryotes and Eukaryotes are two types of cells, with Prokaryotes having characteristics such as a cell membrane, cytoplasm, genetic material, nucleus, and organelles, while Eukaryotes have these same characteristics plus a plasma membrane, mitochondria, dictyosomes, endoplasmic reticulum, ribosomes, microbodies, plastids, cytoskeleton, vacuoles, and nucleus.
• Ribosomes: Small structures composed of RNA and protein, involved in protein synthesis.
• Microbodies: Spherical bodies involved in specific reactions, including glyoxysomes (in plants) and peroxisomes (detoxify peroxides).
• Endoplasmic reticulum: Network of flattened sacs that can be rough (with ribosomes) or smooth (without ribosomes), involved in transport and synthesis of macromolecules.
• Nucleus: Control center of the cell, containing chromatin material.
• Cytoskeleton: Maintains cell shape and provides internal support, including microtubules, intermediate filaments, microfilaments, cilia, flagella, and centrioles.
• Plastids: Organelles with inner and outer membranes and an inner fluid called stroma
• Vacuole: Storage organelle in plants, storing water, salts, proteins, carbohydrates, and waste products.
• Anton Van Leeuwenhoek (1600s) developed the first mini microscope and made detailed drawings of pond water.
• Robert Hooke coined the term "cell" when he looked at slices of cork and dead plant cells.
• Robert Brown (1833) observed the nucleus in cells.
• Matthias Schleiden (1838) stated that all plants are made of cells.
• Theodor Schwann (1839) discovered that all animals are made of cells.
• Rudolph Virchow (1855) stated that all cells come from preexisting cells.
• The cell theory states that all living things are composed of cells, cells are the basic units of structure and function in living things, and all cells come from preexisting cells.
• The shape of a cell is related to its function, with diversity of shapes reflecting diversity of functions.
• The size of most cells is limited by the relationship of the cell's outer surface area to its volume.
• Prokaryotes have a cell membrane, cytoplasm, genetic material, and organelles (only ribosomes), while eukaryotes have a nucleus and additional organelles.
• Parts of a plant cell include the cell wall, plasma membrane, cytoplasm, mitochondria, dictyosomes (Golgi bodies), endoplasmic reticulum, ribosomes, microbodies, plastids, cytoskeleton, vacuoles, and nucleus.
• The cell wall, found in plants, bacteria, and fungi, lies outside the cell membrane and helps protect and support the cell.
• The cell membrane is a phospholipid bilayer that regulates what enters and leaves the cell and provides protection and support.
• Mitochondria are double-membraned organelles that produce ATP (cell energy) and can self-replicate.
• Dictyosomes (Golgi bodies) are disk-shaped sacs that are stacked together and involved in the processing and packaging of proteins.
• Chromoplast- colored

  plastids (include chloroplast

  and carotene
• Leucoplasts – large

  unpimented plastids (include

  proplastids and amyloplasts)
• Proplastid - small, undifferentiated, colourless

  plastids found in dividing meristematic cells from

  which all plastids in differentiated cells originate
• Leucoplast - colorless organelles with various

  functions such as storage as seen in roots, tubers,

  or seeds. The basic function of leucoplast is the

  storage of essential compounds such as starch,

  lipids, and proteins
• Etioplast - photosynthetically inactive plastids

  that accumulate when light levels are too

  low for chloroplast maturation
• Proteinoplast – the leucoplasts that store

  and synthesize proteins for the plant cells only.