The Raw Materials of Biotechnology Chapter 2 Learning

The Raw Materials of Biotechnology Chapter 2

Learning Outcomes n n n n Identify the levels of biological organization and explain their relationships Describe cell structure and its significance in biotechnology research and product development Discuss the types of organisms researched and the types of cells grown and studied in biotechnology facilities plus the products with which they are associated Distinguish between the cellular organization of prokaryotic and eukaryotic cells List the four main classes of macromolecules and describe their structure and function Define genetic engineering and identify products created with this technology Explain the Central Dogma of Biology and its importance in genetic engineering

2. 1 Organisms and Their Components • • To manufacture biotechnology products, biotechnicians must work with organisms and their components. These are the “raw materials” of biotechnology.

Levels of Biological Organization The Living Condition • • Living things include: • Plants • Animals • Bacteria • Fungi • Protozoans Characteristics of life: • Growth • Reproduction • Response to stimuli • Breakdown of food molecules • Production of waste products • • Cells of multicellular organisms are usually grouped into functional units: • Tissues • Organs Cells are the smallest units of life. Some cells contain even smaller, nonliving units.

Vocabulary • • • Fluorometer – an instrument that measures the amount or type of light emitted Organism – a living cell Cell – the smallest unit of life that makes up all living organisms Escerichia coli - a bacterium that is commonly used by biotechnology companies for the development of products Multicellular – composed of more than one cell Cytology – cell biology Anatomy – study of the structure and organization of living things Physiology – the processes and functions of living things Respiration – the breaking down of food molecules with the result of generating energy for the cell Unicellular – composed of one cell Tissue – a group of cells that function together (eg, muscle tissue or nervous tissue) Organ – tissues that act together to form a specific function in an organism (eg, stomach that breaks down food)

Vocabulary • • • Proteins – one of the four classes of macromolecules; folded, functional polypeptides that conduct various functions within and around a cell (eg, adding structural support, catalyzing reactions, transporting molecules) Eukaryotic/eukaryote – a cell that contains membrane-bound organelles Protist – an organism belonging to the Kingdom Protista, which includes protozoans, slime molds, and certain algae Organelles – specialized microscopic factories, each with a specific job in a cell Mitochondria – membrane-bound organelles that are responsible for generating cellular energy Sugar – a simple carbohydrate molecule composed of hydrogen, carbon, and oxygen Starch – a polysaccharide that is composed of many glucose molecules Nucleic acid – a class of macromolecules that directs the synthesis of all other cellular molecules; often referred to as “information-carrying molecules” Lipids – one of the four classes of macromolecules; includes fats, waxes, steroids, and oils Pancreas – an organ that secretes digestive fluids as well as insulin Hormone – a molecule that acts to regulate cellular functions

2. 1 Review Questions 1. Give an example of a plant that has been produced by biotechnology. 2. Knowledge of what other disciplines of science will improve the understanding of biotechnology? 3. Describe two characteristics of living things. 4. Which of the following is considered to be “alive”: organs, molecules, atoms, cells, or organisms?

2. 2 Cellular Organization and Process Cells produce different molecules. Hundreds of different molecules can be produced. • • The Structure of Cells • • Cell walls Cellulose fibers Plasma membrane Nucleus

Plant cell. Most plant cells contain chloroplasts and a rigid cell wall. Animal cells do not. Animal cells do not have a cell wall and, thus, do not have a rigid cell boundary. The shapes of animal cells are quite diverse due to the flexibility of the outer membrane and the response when cells touch each other.

The Central Dogma of Biology states that DNA codes for RNA and that RNA codes for proteins (DNA -> m. RNA -> proteins). Once scientists had described the Central Dogma, they could propose and test strategies for manipulating protein production by manipulating DNA and RNA codes. Moving genes into cells to produce new proteins is the basic principle in genetic engineering.

Shown in cell culture, these CHO cells are a common mammalian cell line used to manufacture recombinant protein. Each rod-shaped structure in this electron micrograph is an E. coli cells are simple prokaryotes with no membranebound organelles, such as mitochondria or chloroplasts.

Types of Cells Used in Biotechnology • • Plant cells Animal cells Bacteria cells Fungal cells

Vocabulary • • • Chlorophyll – green-pigmented molecules found in plants; used for photosynthesis (production of chemical energy from light energy) Photosynthesis – a process by which plants or algae use light energy to make chemical energy Chloroplast – the specialized organelle in plants responsible for photosynthesis (production of chemical energy from light energy) Cytoplasm – a gel-like liquid of thousands of molecules suspended in water, outside the nucleus Lysosome – a membrane-bound organelle that is responsible for the breakdown of cellular waste Ribosome – the organelle in a cell where proteins are made Cell wall – a specialized organelle surrounding the cells of plants, bacteria, and some fungi; gives support around the outer boundary of the cell Cellulose – a structural polysaccharide that is found in plant cell walls Plasma membrane – a specialized organelle of the cell that regulates the movement of materials into and out of the cell Glucose – a 6 -carbon sugar that is produced during photosynthesis reactions; usual form of carbohydrate used by animals, including humans

Vocabulary • • • Adenosine triphosphate – a nucleotide that serves as an energy storage molecule Nucleus – a membrane-bound organelle that encloses the cell’s DNA Chromosomes – long strands of DNA intertwined with protein molecules Enzyme – a protein that functions to speed up chemical reactions Pigments – molecules that are colored due to the reflection of specific wavelengths Messenger RNA (m. RNA) – a class of RNA molecules responsible for transferring genetic information from the chromosomes to ribosomes where proteins are made; often abbreviated m. RNA Amino acids – the subunits of proteins; each contains a central carbon atom attached to an amino group (-NH 2), a carboxyl group (-COOH), and a distinctive “R” group Polypeptides – a strand of amino acids connected to each other through peptide bonds Chinese hamster ovary (CHO) – an animal cell line commonly used in biotechnology studies Vero cells – African green monkey kidney epithelial cells He. La cells – human epithelial cells Prokaryotic/prokaryote – a cell that lacks membrane-bound organelles

2. 2 Review Questions 1. Which of the follow structures are found in prokaryotic cells: a nucleus, ribosomes, mitochondria, a plasma membrane, or one or more chromosomes? 2. Which of the following structures are found in eukaryotic cells: a nucleus, ribosomes, mitochondria, a plasma membrane, or one or more chromosomes? 3. Describe the relationship between chromosomes, m. RNA, and proteins. 4. Explain how so many cells from the same organism can look so different from each other.

2. 3 The Molecules of Cells • • Engineered molecules are the basis of many biotechnology products. Cells are composed of a variety of molecules. Many molecules found in cells are much larger than atoms. Very large molecules are found in structural components.

Carbohydrates • Carbon, hydrogen, and oxygen • Ratio 1: 2: 1 Polysaccharides • Excellent structural and energy-storing molecules • Plants store glucose in starch molecules Monosaccharides • Monomer units that cells use to build polysaccharides • Most well known is glucose; an energy molecule

Structural Formula of Amylopectin is one form of plant starch, and amylose is another. Plant starch, such as corn starch, is a key ingredient in many foods.

Structural Formula Glucose is a 6 -carbon sugar (C 6 H 12 O 5) produced by plants during photosynthesis. Most plants use glucose as an energy source.

Structural Formula 5 -carbon Sugars. Deoxyribose (left) and ribose (right) are structural 5 -carbon sugars found in the nucleic acids, DNA and RNA, respectively. Do you see the difference in their structure?

Disaccharides • Produced when enzymes form a bond between two monosacchrides • Sucrose is made when fructose and glucose are chemically combined Lipids • Often referred to as hydrocarbons • Three groups of lipids • Triglycerides • Phospholipids • Steroids

Structural Formula of Maltose is a disaccharide composed of two glucose molecules bound at carbon No. 1 and carbon No. 4. When organisms digest maltose, the bond holding the glucose monomers together is broken and energy is released.

Proteins • The most important of the cellular molecules • Nine different categories of proteins • Structural • Enzyme • Transport • Contractile • Hormone • Antibody • Pigment • Recognition • Toxins • A typical cell produces more than 2000 proteins • Amino acids are the monomers of proteins • There are 20 different amino acids found in proteins Nucleic Acids • The fourth major group of macromolecules • Two types of nucleic acids • DNA • RNA

Polypeptide Strand. A polypeptide strand is made of amino acids connected to each other through peptide bonds. A folded, functional polypeptide chain is called a protein. Each protein has a specific amino acid sequence and folding pattern.

Two Nucleotides. A nucleotide is a molecule composed of a nitrogenous base (in pink), a 5 -carbon sugar (in yellow), and a phosphate group (in blue).

Vocabulary • • • Macromolecule – large molecule Organic – molecules that contain carbon and are only produced in living things Carbohydrates – one of the four classes of macromolecules; organic compounds consisting of carbon, hydrogen, and oxygen, generally in a 1: 2: 1 ratio Cytoskeleton – a protein network in the cytoplasm that gives the cell structural support Monomers – the repeating units that make up polymers Polymer – a large molecule made of many repeating subunits Monosaccharide – the monomer unit that cells use to build polysaccharides; also known as a “single sugar” or “simple sugar” Disaccharide – a polymer that consists of two sugar molecules Polysaccharide – a long polymer composed of many glucose (or variations of glucose) monomers Fructose – a 6 -carbon sugar found in high concentration in fruits; also called fruit sugar Sucrose – a disaccharide composed of glucose and fructose; also called table sugar Lactose – a disaccharide composed of glucose and galactose; also called milk sugar

Vocabulary • • • Cellular respiration – the process by which cells break down glucose to create other energy molecules Deoxyribose – the 5 -carbon sugar found in DNA molecules Hydrophobic – repelled by water Triglycerides – a group of lipids that includes animal fats and plant oils Ribose – the 5 -carbon sugar found in RNA molecules Phospholipids – a class of lipids that are primarily found in membranes of the cell Hydrophilic – having an attraction for water Steroids – a group of lipids whose functions include acting as hormones (testosterone and estrogen), venoms, and pigments R-group – the chemical side-group on an amino acid; in nature, there are 20 different R-groups that are found on amino acids Ribonucleic acid – macromolecule that functions in the conversion of genetic instructions (DNA) into proteins Nucleotides – the monomer units of nucleic acids

2. 3 Review Questions 1. Which of the following are monosaccharides: cellulose, sucrose, glucose, lactose, fructose, or amyolpectin? 2. Which of the following molecules are proteins that function as hormones: estrogen, insulin, human growth hormone, testosterone, or cholesterol? 3. What distinguishes one amino acid from another? 4. How are the terms nucleotide, nitrogenous base, and nucleic acid related to each other?

2. 4 The “New” Biotechnology • • • The most significant breakthrough came when scientists learned how to move pieces of DNA within and between organisms. The first genetic engineering occurred in 1973. The first genetically engineered product to reach the marketplace was human insulin.

2. 4 Review Questions 1. What term is used to describe DNA that has been produced by cutting and pasting together pieces of DNA from two different organisms? 2. What organism was the first to be genetically engineered? 3. What was the first commercial genetically engineered product?

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