Exam 2

• Peroxisomes contain enzymes that are responsible for oxidizing organic substances.
• Lysosomes are membrane-bound vesicles produced by the Golgi apparatus that contain digestive enzymes.
• Even parts of a cell are digested by its own lysosomes via a process termed autophagy.
• Vacuoles are found in animals but are typically large in plants and used for storage of water, toxic substances, salts, and sugars.
• The toxic substances help protect the plant from herbivorous, or plant-eating animals.
• Peroxisomes contain enzymes that are responsible for oxidizing organic substances. They also contain the enzyme catalase, which breaks down the hydrogen peroxide that builds up in tissues after organic substances are oxidized.
• They also contain the enzyme catalase, which breaks down the hydrogen peroxide that builds up in tissues after organic substances are oxidized.
• Information within the nucleus is transcribed into mRNA and transported outside the nuclear envelope.
• Proteins, which are synthesized by ribosomes, are then released into the rough ER, where they are further folded and modified.
• The smooth ER does not have attached ribosomes and produces lipids, such as steroids.
• Once proteins are folded and modified, transport vehicles called vesicles pinch off and surround them with membranes to be transported elsewhere.
• The vesicles are moved to the Golgi apparatus where they are sorted and packaged.
• Transport vehicles called secretory vesicles carry the macromolecules to the plasma membrane where they fuse and release their contents to the outside environment.
• Chloroplasts have a three-membrane system: an inner and outer membrane surrounds the entire organelle, while a third membrane forms disklike sacs called thylakoids, which are found within the stroma.
• A granum is a stack of these disklike sacs. Chlorophyll and other photosynthetic pigments are found in the membranes of a chloroplasts' thylakoids.
• The enzymes that synthesize carbohydrates during photosynthesis are located in the fluid of the stroma.
• Mitochondria have a two-membrane system: they are surrounded by an inner and outer membrane. The inner membrane is highly folded into cristae that project into the organelle's inner matrix.
• The mitochondria is the site of much of the process of cellular respiration, which produces most of the ATP used by a cell. This process begins as carbohydrates are broken down within the matrix and continues as a chain of proteins in the inner membrane create conditions necessary for ATP synthesis. 
• Often referred to as the "bones and muscles" of an animal cell, the cytoskeleton functions in movement, such as vesicle transport of materials, and support, determining a cell's shape.
• The cytoskeleton is made of three types of protein fibers. Actin filaments provide structural support.
• Intermediate filaments serve to support the nuclear envelope and the plasma membrane. Microtubules serve to maintain the shape of the cell and act as tracks along which organelles can move.
• Although they provide cells with structure, the fibers of the cytoskeleton assemble and disassemble rapidly and result in cells changing shape from one moment to the next
• The motor protein that functions alongside actin to allow for cell movement is called myosin. Two other motor proteins, kinesin and dynein, move along microtubules to help with organelle movement.
• Act as major microtubule organizing center for the cell

  Centrosomes
• Involved in the assembly and disassembly of microtubules, especially during cell division

  Centrioles
• Beat in sweeping motion to transport particles in a single direction or to transport an organism

  Cilia
• Flagella


  Beat in whiplike motion to propel an organism along
• Basal bodies


  Direct movement and organization of microtubules within cilia and flagella
• There are two basic cell types, cells without a nucleus, called prokaryotic cells, and cells that have a nucleus, called eukaryotic cells.
• Two of the three domains of life, the Eubacteria and Archaea, are prokaryotic cells. The third domain, the Eukarya, are all eukaryotic cells.
• As a group, the prokaryotic cells are one of the most abundant and diverse life forms. They can be found in the air, water, and soil, as well as in and on other living things.
• Metabolically, the prokaryotic cells are far more capable than eukaryotic cells. Structurally, the prokaryotic cells are very simple.
• The first cells on earth were prokaryotic cells. Some members of this group, specifically some bacteria, are well known for their ability to cause diseases like anthrax, tetanus, and gonorrhea. 
• Other bacteria are environmentally important decomposers or serve humans in their ability to manufacture chemicals, food, and drugs.
• According to the endosymbiosis theory _____ were engulfed by larger eukaryotic cells.

  mitrochondria
• Mitochondria have an inner membrane system called the thylakoid membranes.

  False 
• _____ are to ribosomes as lipids are to _____.

    Proteins; smooth endoplasmic reticulum 
• The central vacuole


  provides the plant cell with support ,stores nutrients and cellular waste products, stores nutrients and cellular waste products. 
• What is the smallest unit of living matter?

  cell
• chloroplasts are to ____ as ____ are to aerobic respiration

  photosynesthesis; mitochondria