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Protein synthesis and how does it occur?
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*Protein synthesis is the assembling of functional polypeptides in the cytoplasm.
*Protein synthesis occurs through trnaslation, the formation of a linear chain of amino acids, using the information provided by an mRNA strand.
*Provide the physical link between codons and amino acids.
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TRNA
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The amino acids are provied by tRNA - mobile type of RNA. Each tRNA molecule binds and delivers an amino acid of a specific type. Has a tail that binds amino acid. Interacts with mRNA strand.
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MRNA
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Czxc
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Translation - protein synthesis
Step 1
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1. mRNA strand binds to a small ribosomal subunit. The start codon of the mRNA always has the base sequence AUG. It binds to tRNA with the complementary anticodon sequence UAC.
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Translation - protein synthesis
Step 2
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2. When tRNA biding occurs, a large ribosomal subunit joints the complex the create a complete ribosome.
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Translation - protein synthesis
Step 3
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3. A second tRNA arrives at the second tRNA binding site of the ribosome and its anticodon binds to the next codon of the mRNA strand.
TWo mRNA codons are read by a ribosome at any one time.
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Translation - protein synthesis
Step 4
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4. Enzymes of the large ribosomal subunit break the linkage between the tRNA and its amino acid.
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The two main lipids found in the structure of the plasmalemma are
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Cholesterol and phospholipids.
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The plasmalemma is said to be selectively permeable because
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They allow the free passage of some materials and restrict the passage of others
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The movement of solutes from an area of high concentration to an area of lower concentration is an example of
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Diffusion
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The movement of water molecules from an area of high concentration to an area of lower concentration is an example of
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Osmosis
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A solution that contains a solute concentration greater than that in a cell is said to be
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Hypertonic
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Hemolysis occurs when a red blood cell is placed in a(n)
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Hypotonic solution
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Facilitated diffusion is
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A process in which a molecule is carried across a membrane with the help of membrane-bound carriers.
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Active transport is
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A process that requires ATP to pump molecules across a membrane against a concentration gradient.
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