Chapter 4 Cellular Metabolism Flashcards
Metabolic reactions 2types
Anabolic and catabolic reactions
Anabolic reaction
Larger. Molecules are constructed from smaller ones , a process requiring energy
Catabolic reactions
Larger molecules are broken down, releasing energy.
Dehydration synthesis
Removing a molecule of water to join two smaller molecules.
Hydrolysis
Where a molecules of water is inserted into a polymer which is split into 2 smaller molecules
Enzymes
Control the rates of all the metabolic reactions of the cell
Enzyme function
Lower the activation energy of a reaction so it may begin and proceed more rapidly
Each enzyme is specific, acting on only one kind of substrate
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Enzyme reaction
Depends on the number of enzyme and substrate molecules available
How can enzymes (proteins) be denatured?
Heat, pH extremes, chemicals, electricity, radiation, and by other causes
Energy
The capacity to do work
Common forms of energy
Heat, light, sound, electrical, mechanical, and chemical energy
Cells rely on what kind of energy
Chemical energy
Release of chemical energy in the cell often occurs through the
Oxidation of glucose
Glucose molecule
Monosaccharide
Up to ______ molecules of ATP are produced for each molecule of glucose oxidized
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Anaerobic respiration (without oxygen)
First part is splitting of 6-c glucose that occurs through a series of enzyme catalyze steps called glycolysis
2.) result is two 3-c molecules of pyruvate
Glycolysis occurs in the
Cytoskeleton and does not require oxygen
Energy from ARP
Used to start the process but there is a net gain of energy as a result
Aerobic respiration (oxygen needed)
Occurs within the mitochondria
Much greater gain of ATP molecules
Final product of aerobic respiration
Carbon dioxide, water, and energy
Metabolic pathways
A sequence of enzyme- controlled reactions
Specific order
Rate of metabolic pathway
Determined by a regulatory enzyme responsible for one of its steps
Deoxyribonucleic acid (DNA)
Contains the genetic code needed for the synthesis of each protein(including enzymes)
Genetic information
A gene is a portion of DNA molecule that contains the genetic information for making a single protein.
Genome
All the DNA
Nucleotides of DNA form a
Sugar-phosphate backbone with bases extending into the interior of the DNA molecule
DNA replication
Each new cell must be provided with an exact replica of the parent cells DNA
When does DNA replication occur
During interphase
DNA replication
DNA molecule splits
Nucleotides form complementary pairs with the original strands
DNA strands are compatible with those in the other strand…. What can be in the other strand
Adenine pairs with thymine; cytosine with guanine
RNA
Copy and transfer specific info to the cytoplasm where proteins are manufactured
RNA molecules
Single-stranded and contain ribose rather than deoxyribose, and uracil rather than thymine
Messenger RNA (mRNA) molecules
Synthesized in the nucleus in a sequence complementary to the DNA template in a process called transcription
