Biology Unit 2 - Macromolecules

If you ate a samples of the different carbohydrates seen here, how would the available energy differ from each source and why?

All of the carbohydrates would produce about the same amount of energy, as they all have a large amount of oxygen atoms.

Almonds may be small, but they pack a great number of nutrients, including protein, vitamin E, and vitamin B2. Almonds also contain antioxidants and monounsaturated fat, a "good" type of fat that, like the omega-3 fatty acids, reduces the risk of heart disease. Review the graph that represents the whole class data. Notice that the almond samples provide a large amount of chemical energy. Select which of these is the BEST explanation for this large amount of available energy?

Fats and proteins are molecules with many chemical bonds; the bonds release much energy when broken.

Amino acids are the monomers of proteins. Which functional group in the amino acid determines its specific shape and function?

R group

DNA and RNA are both nucleic acids made up of nucleotides. Which is NOT a difference between DNA and RNA?

RNA contains adenine, thymine, cytosine, and guanine.

Scientists use DNA sequencing to understand relationships among life on Earth. The chart illustrates differences between five species and humans. Although the DNA sequence of each may vary, all BUT ONE statement concerning the organisms is true

The DNA sequences may vary but the amino acid sequences are identical.

In an experiment involving an enzyme, the pH is raised from 2 to 11. What will be the MOST LIKELY effect of this on the reaction?

The enzyme will denature, stopping the reaction.

Cellulose and starch are both polysaccharides. Polysaccharides are polymers of monosaccharides sometimes referred to as complex carbohydrates because of their length. Polysaccharides may function in energy storage or as structural components of organisms. Pictured is cellulose, the most abundant carbohydrate. Identify a difference between the two polysaccharides cellulose and starch.

The main difference between cellulose and starch is the function they perform in plants.

Imagine the pH of the environment in which the hydrolysis of sucrose is to occur has dropped to 2.How will this drop in pH influence point D in the model?

The substrate (A) will no longer fit into the active site (C) because the enzyme has changed shape.

Check out the illustration above. Using the CORRECT terminology, matched with the correct lettered structures, explain how all are related to inheritance.

This is a cell (B) with a nucleus (C) containing DNA (A). The DNA is organized into chromosomes (D). A section of the chromosome that codes for a trait is called a gene (E).

Which of these is a segment of DNA that contains the information necessary to produce a protein?

a gene

This is a picture of sucrose, a disaccharide, a molecule composed of two monosaccharides: glucose and fructose. Macromolecules are formed when monomers are bonded together. The different macromolecules have different monomers and different types of bonds. Which of these does NOT correctly pair the monomer and the bond used to make a polymer?

amino acid; hydrogen bond

All BUT one of the following is a component of nucleic acids. Nucleic acids DO NOT contain

amino acids

DNA is double stranded helix, connected by what could be described as "ladder rungs". These rungs are actually nucleotides, the building blocks of DNA. A sequence of three of these nucleotides is known as a codon. Codons are important in the composition of proteins, because each codon calls for a specific ____________.

amino acids

Proteins are important biomolecules that build organisms and direct chemical reactions. Proteins are polymers composed of long chains of

amino acids.

Intermolecular forces hold biomolecules together. They are also found between biomolecules. Which of these is a place you would expect to find a hydrogen bond in a biomolecule?

between adenine and thymine in DNA

Carbohydrates, fats, proteins: These organic molecules ALL have this element in common. This element can form multiple bonds, and it bonds with other elements as well as with itself. This element is

carbon

Lipids are important to living things for all of the following reasons, EXCEPT that they are

chained together to form proteins

Car wax mostly contains beeswax and carnauba wax. Which of these does NOT accurately describe waxes?

contain fatty acids, glycerol, and a phosphate group

If you ate a jelly doughnut for breakfast, the majority of the energy would come from the _________ in the doughnut because it _________.

fat; contains a low ratio of oxygen atoms.

Cholesterol is synthesized by all animal cells and is an essential structural component of animal cell membranes. Cholesterol is the most common steroid and is mainly synthesized in the liver. Cholesterol also serves as a precursor for several important biological compounds including all, EXCEPT:

insulin

The biomolecule described is a · cell membranes · large biomolecule · many high energy bonds · nonpolar covalent bonds · includes waxes and steroids · consists mainly of carbon and hydrogen · more energy per gram than other biomolecules

lipid

Food that is high in calories and could be used for energy storage in animals is MOST LIKELY high in

lipids

It is advantageous for animals that migrate to store energy in the form of lipids rather than carbohydrates. This is because

lipids weigh less and store more energy than carbohydrates.

A food that is high in calories and could be used for energy storage in animals is MOST LIKELY high in

lipids.

Many plants have leaves and fruits have wax coatings. Some animals also have wax-coated fur or feathers. In which class of biomolecules do waxes belong AND what characteristic of these molecules makes them well-suited for their role in plants and animals?

lipids; hydrophobic

Which type of nucleic acid is responsible for the transmission of information from the genetic code in the nucleus to the ribosome?

mRNA

You and your lab partner place 2 g slices of liver into 3 test tubes containing water, vinegar, or baking soda. You add 15 ml of hydrogen peroxide to each and measure the amount of oxygen produced every 30 seconds for 3 minutes. Now that you have completed the experiment, you need to graph your results. You decide to make a triple line graph showing the rate of reaction (oxygen produced/30 sec.) for each of the three solutions. On your graph, where should you put the oxygen production?

on the y axis because it is the dependent variable

Amino acids are the building blocks of proteins. Which of these best describes an amino acid?

organic

The graph illustrates the activity level of three common digestive enzymes, across a range of pH values. Which enzyme is likely to be the most active in the acidic environment of the stomach?

pepsin

A ___________ chain is a sequence of amino acids that is the foundation for the basic structure of a protein.

polypeptide

In humans, excess blood glucose is stored in the liver and in muscle tissue in the form of glycogen. Glycogen is a long chain of glucose molecules bonded together. Because of this, glycogen is called a _____________________.

polysaccharide

All the biological macromolecules contain Carbon, hydrogen and oxygen. However, most do not contain nitrogen. The category that contains nitrogen are

proteins

Both the microscopic organisms seen here are motile. Although they have different methods of locomotion, they use extensions that are composed of the same macromolecules. What is the macromolecule that builds both cilia and flagella?

proteins

Receptors that are __________ bind to chemicals outside of the cell, and this binding process causes a chemical response on the inside of cells.

proteins

This is a nucleotide. If C is uracil, B is _______________ and the nucleotide comprises _____________.

ribose; RNA

The level of protein structure that involves interactions between the side chains of the amino acids rather than interactions between molecules within the backbone is:

tertiary

Which of these correctly demonstrates the biomolecule with its function?

waxes; prevents water loss and repels water

You inherit the DNA that composes your chromosomes from your mother and your father. You have inherited a protein that STOPS the production of an enzyme, a protein, to help you digest milk. Scientists have figured out that this protein contains an amino acid that really does say STOP whenever the enzyme starts to be produced. What nitrogen bases, found in your DNA, could be arranged to produce this STOP amino acid?

A, T, and C

Hormones; cholesterol. Which group of lipids represents steroids?

A.

During the laboratory, the students laid the food samples on brown paper, like the kind of paper that lunch bags are made out of. Both the chip and the pecan left translucent spots on the brown paper. What does this tell you about the source of the food energy supplied by these sample?

Both the chip and the pecan are a high in fats/oils.

Living things require specific organic molecules in order to survive. The picture above represents some specific examples of foods that are mainly composed of one of these necessary organic molecules. The organic molecules found in these types of food are

Carbohydrates

Steroids are classes of lipids that include cholesterol, sex hormones, and cortisone. Steroids are not hydrocarbon chains like triglycerides, but instead contain four fused carbon rings. Although steroids can bond to fatty acids, steroid molecules do not contain a fatty acid chain, and the monomer of a steroid biomolecule is difficult to define. Which of these does NOT correctly pair a steroid and its function?

Cholesterol is an energy source.

Complex carbohydrates, such as fruits and vegetables, are universally viewed as healthier than simple carbohydrates like sugar. Why are complex carbohydrates a better dietary choice?

Complex carbohydrates require more energy to be broken down so they are less likely to lead to weight gain.

The molecular sequence, or blueprint for a protein, is originally carried by which molecule?

DNA

Glucose, a monosaccharide, is found in three different polysaccharides: starch, glycogen, chitin. There are differences between the structure and function of the glucose arrangement found in these polysaccharides. Which statement CORRECTLY distinguishes the difference in glucose structure in one of these polysaccharides?

Glucose molecules are joined in a long chain to make starch that is easily digested for energy.

Steroids differ structurally from triglycerides and phospholipids, although they are all classified as lipids. What characteristics cause steroids to be classified as lipids? Choose ALL that apply.

I and V

Plants often have wax coatings that help them to conserve water. Which of the statements above describe waxes?

II and IV

If the chemical enzyme pepsin was mixed with some proteins in a test tube in a laboratory, which of these outcomes would you predict?

Pepsin would probably NOT break down proteins in the test tube because pepsin is designed to work at very acidic pH ranges.

A healthy diet consists of carbohydrates, fats, and proteins. Proteins are broken down into amino acids that are recombined to make many of the body's structures, such as muscle. Eating protein regularly is of utmost importance because ____________.

The body doesn't have any mechanism for storing amino acids.

Compare the food energy in calories from burning the chip and the saltine. How can you explain this differences in terms of chemical composition?

The chip contains more lipids than the saltine.

One of the group members burning the saltine and the chip disagreed with the hypothesis. "The two foods both contain starch," was the student's rational for her objection. "The temperature difference is a result of measurement error." How would you respond to this student?

The original hypothesis is correct because the chip also contains lipids, which are larger macromolecules.

DNA, RNA, and starch: What do these three important biomolecules have in common?

The presence of at least one carbon-based sugar.

Amylase becomes denatured at a temperature of 80°C. During an experiment to study the effect of varying temperature on enzyme activity, amylase's reactivity with starch was measured at body temperature (37°C), and then again at an increased temperature of 42°C. How would this increase in temperature affect the experiment?

The rate of reaction will increase.

Students in biology are studying the macromolecules of life. They used a calorimeter to determine the calories in various types of food. Once the lab was completed, the students ate the left over food samples. Monica commented that in just 6 or 7 "chews" of the saltine, it was gone; nothing but a sticky paste in her mouth. Elaborate on what happened chemically while chewing the saltine. Include the macromolecules present.

The saltine is a carbohydrate. and digestion took place in Monica's mouth thanks to enzymes or proteins. The blueprint for these proteins is located on nucleic acids

During the process of protein synthesis, each tRNA carries one

amino acid

A researcher discovers a small molecule in muscle tissue that is rich in nitrogen, soluble in water, and lacks phosphorus. The molecule also contains carbon, hydrogen, and oxygen, in uneven ratios. The molecule must be a(n)

amino acid.

Membrane proteins are among the most important proteins biologically because they allow cells to communicate with their environments. In humans, they determine whether the immune system recognizes the cell as foreign or not and they are the targets of most __________.

drugs

Valine is an amino acid used to make proteins. It is an essential amino acid meaning the body cannot synthesize it and thus, it must be obtained from food sources. Its side chain is an isopropyl group. What property of valine would you expect from this side chain?

It is hydrophobic.

____________ are cellular macromolecules containing hydrogen, oxygen, nitrogen, carbon and phosphorous.

Nucleic acids