Biology Exam 1

How many molecules of water are needed to completely hydrolyze a polymer that is 11 monomers long? A.10 B. 12 C. 11 D.9 E. 8

10

In an analysis of the nucleotide composition of DNA, which of the following will be found? A. G+C +T+A B. A=G AND C=T C. A=C D. A+C=G+T

A+C=G+T

What are the four nitrogenous bases found in RNA?

Adenine uracil guanine cytosine

Lactose, a sugar in milk, is composed of one glucose molecule jioned by a glycosidic linkage to one galactose molecule. How is lactose classified? A. as a disaccharide B. as a monosaccharide C. as a hexose D. as a polysaccharide E. As a pentose

As a disaccharide

The difference between the sugar in DNA and the sugar in RNA is that the sugar in DNA A. Can form a double-stranded molecule B. Is an aldehyde sugar and the sugar in RNA is a keto sugar C. Contains one less oxygen atom D. is in the a configuration and the sugar in RNA is in the B confirmation E. is a six carbon sugar and the sugar in RNA is a five-carbon sugar

Contains one less oxygen atom

Micofilaments such as actin, microtubules and the intermediate filaments form the cell-supporting structure called the: A. cytoskeleton B. ectoplasm C. plasma membrane D. nuclear envelope

Cytoskeleton

Which chemical group forms hydrogen bonds with water and is most likely to explain why sugar dissolve well in water? A. -C-C B.-C-H C.-N-H D. -O-H

D. -O-H

Two carbon atoms joined to each other by sharing of two pairs of electrons, form a(n): A. ionic bond B.SIngle covalent bond C. Hydrogen bond D. Double covalent bond

Double covalent bond

Sudan IV, a dye that binds to nonpolar molecules is used to detect the presence of a class of macromolecules in food. Sudan IV would bind to in the presence of what macromolecule? A. Fats B. Proteins C. Chitin D. DNA E. Starch

Fats

The organelle that can collect, package, modify and transport molecules is called the A. Receptor-mediated endocytosis B. Mitochondria C. transport vesicle D. Golgi Apparatus

Golgi Apparatus

Water molecules are polar with ends that exhibit partial positive and negative charges. These opposite charges allow water molecules to attract each other through.. A. peptide bonds B. Covalent bonds C. Hydrogen bonds D. Ionic Bonds

Hydrogen bonds

The pH of your small intestines is around 7.5 and the pH of your large intestine can be 5.5. As substances travel from the small intestines to the large intestine, what happens to the H+ ion concentrations? A. it decreased 2 fold B. It increases 2 fold C. It increased 10 fold D. It decreases 100 fold E. It increases by 100 fold

It increases by 100 fold

DNAse is an enzyme that catalyzes the hydrolysis of the covalent bonds that join nucleotides together. What would first happen to DNA molecules treated with DNAase? A. The pyrimidines would be separated from the deoxyribose sugars. B. The two strands of the double helix wold separate C. All bases would be separated from the deoxyribose sugars D. The phosphodiester bonds between deoxyribose sugars would be broken E. The purines would be separated form the deoxyribose sugars.

The phosphodiester bonds between deoxyribose sugars would be broken

Which of the following is true of both starch and cellulose? A. They are both structural components of the plant cell wall. B. They are both used for energy storage in plants C. They are both polymer of glucose D. They can both be digested by humans E. They are cis-trans isomers of each other

They are both polymers of glucose

Membrane lipids contain long chains of H-C-H groups joined by C-C bonds. Which interaction is most likely occurring between lipids in the membrane? A. Hydrogen bonds B. Covalent bonds C. Van der Waals D. Ionic bonds

Van der Waals

In animal metabolism, most of the monomer released by digestion of food macromolecules are metabolized to provide energy. Only a small portion of these monomers are used for synthesis os new macromolecules. The net result is that: A. Water is generated by animal metabolism B. Water is generated during homeostasis, but water is consumed during periods of growth C. Water is consumed by animal metabolism D. Water is consumed during homeostasis, but water is generated during growth periods E. The water consumed is exactly balanced by the water generated, to maintain homeostasis

Water is consumed by animal metabolism

There are 20 different amino acids. What makes one amino acid different from another? A. different side chains (r groups) attached to an alpha carbon B. different side chains (r groups) attached to a carboxyl carbon C.different side chains (r groups) attached to the amino groups D. Different structural and optical isomers E. Different asymmetric carbons

different side chains (r groups) attached to an alpha carbon

Which type of interaction stabilizes that a helix and the B pleated sheet sturctures of proteins? A. hydrophobic interactions B. peptide bonds C. disulfide bonds D. ionic bonds E. hydrogen bonds

hydrogen bonds

A distinctive feature of eukaryotes is the organization of tightly packaged chromosomal DNA with proteins into a membrane- bound structure called a : A. cell B. nucleus C. lysosome D. nucleolus E. RER

nucleus

Which bonds are created during the formation of the primary structure of a protein? A. peptide bonds B. peptide bonds, hydrogen, and disulfide bonds C. Hydrogen bonds D. Disulfide bonds E. Phosphodiester bond

peptide bonds