Bs801

BS801 Genes R Us Questions for study: 1. What functions do transcription and translation carry out, and where are they carried out in the cell? Transcription: process of creating an equivalent RNA copy of a sequence of DNA Transcription is the first step leading to gene expression. The stretch of DNA transcribed into an RNA molecule is called a transcription unit and encodes at least one gene. Occurs in nucleus of the cell Translation: Translation is the production of proteins by decoding mRNA produced in transcription. Translation occurs in the cytoplasm where the ribosomes are located. In translation, messenger RNA (mRNA) is decoded to produce a specific polypeptideaccording to the rules specified by the genetic code. This uses an mRNA sequence as a template to guide the synthesis of a chain of amino acids that form a protein. 2. Which of the kingdoms of organisms are characterized by unicellularity (the organism has only one single cell)? Protista 3. Bacteria and archaea are both prokaryotes, but they have very different characteristics. How would you compare archaea and bacteria? Archaea cell membrane contains ether linkages cell wall lacks peptidoglycan genes and enzymes behave more like Eukaryotes have three RNA polymerases like eukaryotes extremophiles 4. What process can lead to shrinkage or swelling of a cell? Osmosis 5. What are the different kinds of fibers that make up cytoskeleton? Cells contain elaborate arrays of protein fibers that serve such functions as: Bacteria cell membrane contains ester bonds cell wall made of peptidoglycan have only one RNA polymerase react to antibiotics in a different way than archea do

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establishing cell shape providing mechanical strength locomotion chromosome separation in mitosis and meiosis intracellular transport of organelles

The cytoskeleton is made up of three kinds of protein filaments:

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Actin filaments (also called microfilaments) Intermediate filaments and Microtubules

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