Ch. 2 - The Cytoplasm Flashcards
What is the functional and structural unit of a tissue?
The cell
Eukaryotic cell
Cells with distinct membranous nuclei surrounded by cytoplasm containing membrane-bound organelles
Larger than prokaryotic cells
I.e. animals
Prokaryotic cell
Cells with a cell wall around the plasmalemma and lack membranous structures
Smaller than eukaryotic cells
I.e. bacteria
Zygote
The single cell formed by the merger of a spermatozoon with an oocyte at fertilization
Blastomeres
Cells produced by the first zygotic cellular divisions
Give rise to all tissue types of the fetus
Embryonic stem cells
Pluripotent stem cells derived from the inner mass of the embryo
Cell differentiation
Specialization of embryonic stem cells
Cells synthesize increased quantities of specific proteins and become very efficient in specialized functions
Often change shape to match function
What is an example of cell differentiation?
Muscle cell precursors elongate into fiber-like cells containing large arrays of actin and myosin
Name the specialized activity of muscle and contractile cells.
Movement
Name the specialized activity of epithelial cells.
Form adhesive and tight junctions between cells
Name the specialized activity of fibroblasts and the cells of bone and cartilage.
Synthesize and secrete components of the ECM
Name the specialized activity of neurons and sensory cells.
Convert physical and chemical stimuli into action potentials
Name the specialized activity of cells of the digestive glands.
Synthesis and secretion of degradative enzymes
Name the specialized activity of cells of mucous glands.
Synthesis and secretion of glycoproteins
Name the specialized activity of certain cells of the adrenal gland, testes and ovaries.
Synthesis and secretion of steroids
Name the specialized activity of cells of the kidney and salivary gland ducts.
Ion transport
Name the specialized activity of macrophages and neutrophils.
Intracellular digestion
Name the specialized activity of fat cells.
Lipid storage
Name the specialized activity of cells lining the intestine.
Metabolite absorption
Specialized functions _______ be performed by most cells of the body.
can
Specialized cells just have an expanded capacity for these functions
Cytoplasm
Surrounds the nucleus
Nucleus
Membrane-bound organelle found in eukaryotic cells that holds the genetic material
Plasma membrane or Plasmalemma
Outermost component of the cell
Separates the cytoplasm from the extracellular environment
Selective barrier, regulating that passage of materials in and our of the cell and facilitating transport of specific molecules
Maintains the ion content of cytoplasm
Integrins
Proteins of the plasma membrane that link the cytoplasm and the ECM
Cytosol
Fluid inside the cytoplasm that bathes the organelles
Organelle
Metabolically active structures within the cell cytoplasm
May be membranous or nonmembranous
Cytoskeleton
Determines the shape and motility of eukaryotic cells
Inclusions
Deposits of carbohydrates, lipids, and pigments
What is the plasma membrane made up of?
Amphipathic phospholipids consisting of long-chain fatty acids linked to a hydrophilic head that bears a phosphate group
Form a phospholipid bilayer
Cholesterol molecules insert at varying densities among the bilayer to provide rigidity to restrict movement
The outer layer contains glycolipids which contribute to the glycocalyx
Glycolipids
Outer lipids of the plasma membrane
Include oligosaccharide (sugar) chains that extend outward from the cell surface and contribute to the glycocalyx
Integral proteins
Proteins that are directly incorporated within the lipid bilayer and permanently attached to it
Can only be extracted from cells via detergents that disrupt lipids
All transmembrane proteins are integral proteins, but not all integral proteins are transmembrane proteins
Peripheral proteins
Proteins that are temporarily attached to the lipid bilayer
Can ge easily extracted from cells via salt solutions
Transmembrane proteins
Proteins that span the bilayer (from one side to the other)
All transmembrane proteins are integral proteins, but not all integral proteins are transmembrane proteins
Carbohydrate moieties of glycoproteins project from the _______ surface of the plasma membrane and are important components of proteins acting as _______.
receptors
The distribution of membrane polypeptides is _______ in the two surfaces of the cell membranes. Therefore, all membranes in the cell are _______.
different; asymmetric
