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Cards In This Set
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What is a peptide?
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A molecule formed by joining two or more amino acids. When the number of amino acids is less than about 50 these molecules are named peptides while larger sequences are referred to as proteins. Peptides (proteins) are present in every living cell and possess a variety of biochemical activities. They appear as enzymes, hormones, antibiotics, receptors, etc.
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What is a protein?
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Biochemical compounds consisting of one or more polypeptides typically folded into aglobular or fibrous form, facilitating a biological function. Many proteins are enzymes that catalyze biochemical reactions and are vital to metabolism. Proteins also have structural or mechanical functions, such as actin and myosin in muscle.
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What are some protein functions?
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Enzymes; transporters in membranes; receptors for hormones, neurotransmitters, drugs, etc.; structural support (cytoskeleton, collagen, etc.); hormones and neurotransmitters.
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What is the primary structure of a protein?
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The sequence of amino acids composing the polypeptide chain. The chain assumes certain recurring structural patterns
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What is the secondary structure of a protein?
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The bond angles created by bonded amino acids form the alpha-helix shape which makes helical turns in a clockwise direction like a screw. Hydrogen bonds stabilize the spirals of the chains, usually by connecting a hydrogen atom of one amino acid and the peptide bond oxygen of another amino acid
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What is the tertiary structure and how does it differ from the quaternary structure?
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Tertiary structure is the third structure that forms out of the bending and folding of the helices and pleated sheets. Quaternary structure is made up of more than one polypeptide chain.
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What are two different types of nucleic acids?
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Deoxyribonucleic acid (DNA), which is found in the nucleus and contains the genes; and ribonucleic acid (RNA), which is an intermediary molecule that puts the DNA genetic information to work in the cell.
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What is a nucleotide and what are the 3 basic parts of a nucleotide?
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Nucleotides are the monomers that compose nucleic acids. They link together by dehydration synthesis. They consist of sugar, phosphate, and nitrogen bases (A,T,G,C)
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What are three structural differences between RNA and DNA?
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DNA is found in the nucleus; is made of deoxyribose (the sugar); is involved in transcription; is double stranded; and includes the bases A,C,G,T. RNA is found in the nucleus, cytoplasm, ribosomes, and rough ER; is made of ribose (the sugar); is involved in transcription AND translation; is single stranded; and includes the bases A,C,G,U.
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Where is DNA and RNA found in the cell?
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DNA is found in the nucleus, and RNA is found in the nucleus, cytoplasm, ribosomes, and rough ER.
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What is an enzyme?
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An enzyme is a biological catalyst (usually proteins)
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How do enzymes act as catalysts? Are they specific and selective?
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Enzymes reduce the amount of activation energy required for a chemical reaction, therefore speeding up the reaction. They are highly specific because the enzyme and substrate must have an exact molecular fit.
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Fibers of the cytoskeleton
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Microfilaments, intermediate filaments, microtubules; provide structural support and direct transport and movement of organelles
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Which organelles are found in animal cells only? Which are found in plant cells only?
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Animal cells: centrioles, lysosomes, flagella/ciliaPlant cells: chloroplasts, cell wall, vacuole
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Cell Membrane
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It separates the cell from other cells and helps regulate what is transported in and out of the cell by selective permeability.
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