Hole's Essentials of Human Anatomy & Physiology Chapter 4 - Cellular Metabolism

Calculate the number of amino acids encoded by a DNA sequence of 27 nucleotides.

9

define gene expression

A gene that is transcribed and translated into a protein.

Distinguish between anabolism and catabolism

Anabolism uses energy to build large molecules from smaller ones. Catabolism releases energy by breaking large molecules into smaller ones.

Explain the importance of ATP, and the relationship of ATP to ADP.

ATP is the primary energy-carrying molecule in the cell. It acts as a rechargeable battery for cellular processes by carrying energy in the terminal bond of the phosphate molecule and returning to recapture energy when it is used. Without ATP, the cell would die.

Distinguish between dehydration synthesis and hydrolysis

Dehydration synthesis joins many simple sugar molecules to form larger molecules of glycogen Hydrolysis breaks down carbohydrates, lipids and proteins, and splits a water moleculte in the process.

Distinguish between anaerobic and aerobic phases of cellular respiration.

During cellular respiration, the oxidative processes that occur in the absence of oxygen are called anaerobic respiration. The oxidative processes that require the presence of oxygen for their reactions are called aerobic respiration.

Explain why enzymes are important in the body.

Enzymes are proteins that control the speed of chemical reactions in your body. Without enzymes, these reactions would take place too slowly to keep you alive

Identify the cellular respiration pathway where glucose, fats, and proteins commonly enter.

Glucose is broken down into 38 molecules of ATP. Half of the energy goes to ATP synthesis and the other half goes to heat. Complete oxidation goes to carbon dioxide and water. Proteins and fats are broken down to release energy for ATP synthesis. The final process is aerobic respiration.

Define active site

Part of enzyme that temporarily binds a substrate

Define metabolic pathway

Sequences of enzyme controlled reactions that lead to synthesis or breakdown of particular biochemicals

If a strand of DNA has the sequence A T G C G A T C C G C, then the sequence of an mRNA molecule transcribed from it is ___________

TACGCTAGGCG

Describe the events of DNA replication.

The DNA molecule splits. Nucleotides form complementary pairs with original strands.

Explain how oxidation of molecules inside cells differs from burning materials outside of cells

The burning of a substance outside the cell usually requires large amounts of energy to start the reaction. This burning indiscriminately breaks all chemical bonds in the substance and releases the energy as light and heat. Oxidation inside the cell utilizes enzymes that require less activation energy, controls the by-products released, and uses certain energy capturing molecules to trap about one-half of the released energy for use elsewhere. The rest is lost as heat.

Explain why DNA replication is essential

The new cell must have a copy of original cells genetic information so it will be able to synthesize the proteins to build cellular parts and metabolize.

Explain how one enzyme can control the rate of a metabolic pathway

The rate of a metabolic pathway is often determined by a regulatory enzyme that catalyzes one of its steps

Explain the function of cellular metabolism

The set of chemical reactions that acquire, store, and release energy in cells.

Define cofactor

a nonprotein component which make some enzymes active

citrus acid cycle

acetyl CoA molecules are broken down to release CO2 and highenergy electrons

Exposure to radiation can _____ an enzyme and change its shape to the point where it becomes inactive.

denature

Describe how an enzyme interacts with its substrate

each enzyme has a particular substrate. a substrate joins with its enzyme to form an enzyme-substrate complex with creates a product and the unchanged enzyme

Distinguish between a gene and a genome.

gene: The portion of a DNA molecule that contains the genetic information for making a particular protein genome: The complete set of genetic instructions in a cell

glycosis

glucose molecules are broken down

Identify the final acceptor of the electrons released in the reactions of cellular respiration.

oxygen

DNA information provides instructions for the cell to ________

synthesize protein molecules

describe the function of a ribosome in protein synthesis

tRNA carries its amino acid to a correct position on an mRNA strand which occurs on ribosomes.

electron transport chain

the final electron acceptance is oxygen

Distinguish between transcription and translation.

transcription occurs in the nucleus and DNA is transcribed into mRNA translation occurs in the cytoplasm and is where mRNA is translated from language of nucleic acids to language of amino acids