WGU C190 INTRODUCTION TO BIOLOGY ALL TEST QUESTIONS AND ANSWERS VERIFIED EXAM 2026

WGU C190 INTRODUCTION TO BIOLOGY ALL TEST QUESTIONS AND ANSWERS VERIFIED EXAM 2026 Fats and oils are composed of - -Fatty acids and glycerol Fatty acids can naturally be saturated or unsaturated. A saturated fatty acid has - -. All single covalent bonds Triglycerides, a type of fat, are composed of what two subunits? - -Fatty acids and glycerol What would you have to do to make a fat from the fatty acid shown above? - -Attach it to a glycerol along with two other fatty acids. If one or more of the fatty acids in a triglyceride include omega-3 fatty acids, what can you predict about this substance at room temperature? - -It is a liquid oil What kinds of molecules are the major fuel for the salmon's long trip? - -Triglycerides (fats / oils) Based on your knowledge of the structure of triglycerides, what products would you expect to result from the complete hydrolysis of a fat molecule? More than one is correct. - -Fatty acids and glycerol The blubber layer helps insulate mammals and birds that live in cold water; fat does not conduct heat very quickly. Applying what you know about lipids, what is the main advantage of covering feathers or fur in oil? - -Oil sheds water and keeps underlying layers of fur or downy feathers dry. Another type of lipid that composes cells are called phospholipids. Phospholipids differ from other lipids because they - -Contains a hydrophobic and hydrophilic end Highly simplified diagram of a membrane's structure is made up of - -Phospholipids Which part of the molecules is hydrophilic? - -The heads Ions of salt (sodium, NA+, and chloride, Cl−) are highly hydrophilic. Will they easily pass through the layer to enter or leave a cell? - -No. What are molecules? - -Molecules are made of atoms Below is an image of the smallest amino acid: Glycine. What does each line in the picture of the amino acid represent? - -A shared pair of electrons in a covalent bond. A peptide is built so that the red amino acid is glutamic acid and the blue amino acid is lysine. How will these amino acids respond to each other? - -These amino acids are charged and will attract each other The amino acid chain of a protein is held together by - -Covalent bonds If the protein is mainly structural and needs to maintain a stable, rigid form, which bonds would it use? - -Covalent bonds If the protein needs to be flexible, with bonds that easily break and reform, which bonds would it use? - -Hydrogen Water molecules binding to each other is called a - -Cohesion Water molecules binding to other molecules is called - -Adhesion Water molecules form hydrogen bonds because water is - -Polar Water can bind to the walls of these cells because they are - -Polar When water binds to the walls of the cells, this is called an - -Adhesion Water molecules within these cells will also bind to each other. What is this called? - -Cohesion Dissolving sugar in water makes a - -Solution The sugar is the - -Solute The water is the - -Sovent As water moves up the plant, it carries matter with it (such as nutrients and some hormones). What are these materials called? - -Solutes What characteristic of water allows this paperclip to float on the surface of the water? - -Surface tension Why does mercury (Hg) not travel as far up the capillary tube as water does? - -Mercury is not as adhesive as water If the plant gets too dry, the water column can break. This creates an air bubble in the xylem. What happens to the water when the air bubble forms? - -The water is still adhering to the xylem walls, but the water column is no longer continuous Explain why plants produce smaller cells during dry seasons? - -The smaller cells are more resistant to air bubbles Explain why plants produce larger cells during wet seasons? - -These cells can transport more water Which molecule is abundant in seeds and is easily digested to yield glucose? - -Starch Both starch and glucose have what primary function? - -Fuel / storage of energy Hydrophobic molecules - -Does not interact with water Nonpolar molecules that lack highly electronegative atoms such as oxygen are - -Hydrophobic Ionic substances and polar molecules are - -Hydrophilic Nonpolar molecules are - -Hydrophobic is the most abundant organic molecule on planet Earth. It is a polysaccharide that is used as a structural material in the cell walls of plants. - -Cellulos Starch is an easily used starting point for fuel production. Why is it much harder to use cellulose for the same purpose? - -Cellulose is difficult to hydrolyze (digest) Cellulose is naturally found in many foods, and it is used as an added ingredient in many health food products. Why might cellulose be a "healthy" addition to bread or breakfast cereal? - -It slows the absorption of sugar from food into the blood Steroids are classified as lipids because they are hydrophilic? - -The carbon rings are hydrophobic due to the carbon to hydrogen bonds that are nonpolar. Steroids are composed of fatty acids like triglycerides and phosopholipids? - -Does not contain fatty acid Steroids are lipids that have unique structures. What description best describes steroids? - -Four fused carbon rings Cholesterol is a starting point for making vitamins A and D. What other important substance(s) are made by modifying cholesterol? Select all that apply? - -Sex hormones; bile acids Trans fats are naturally occurring fatty acids? - -Made by man What units (monomers) make up a protein? - -Amino acids Which of the functions below is provided by collagen proteins? - -Provide structure in a cell or on a larger scale Which of the functions below is provided by p53 proteins? - -Produce, manage, repair, or regulate DNA in some way Cancer cells have faulty DNA and they divide rapidly in an uncontrolled manner. What would you predict about the effect of a mutation that destroys the function of p53? - -A loss-of-function mutation to p53 would contribute to cancer by removing a "brake" on cell division Enzymes can catalyze different types of reactions. If the reaction involves breaking a substrate into products the reaction would be? - -Catabolic The reaction above is also described as being? - -Hydrolysis Maltose, a milk sugar, is broken down into two monosaccharides called galactose and glucose by maltase. Maltase allows the reaction to occur at the body temperature of the organism. In this example, the substrate(s) is (are) - -Maltose In this example, the enzyme(s) is (are)? - -Maltase In this example, the product(s) is (are)? - -galactose and glucose In this example, maltose is broken down into galactose and glucose. This is an example of these types of reactions? - -Hydrolysis and catabolism When a polypeptide from food attaches to pepsin, pepsin changes shape and the polypeptide is hydrolyzed and broken into smaller pieces. Which best describes the situation? - -Pepsin is an enzyme and binds to the green polypeptide at pepsin's active site; the green polypeptide is the substrate Which of the functions below is provided by ferritin proteins? - -Transport material long-distance, e.g. through circulation in blood The four charged amino acids at the opening of the pore attract potassium (K+) ions, increasing the rate at which they pass into the channel. Which charge do you predict must be indicated by the red color? - -Negative charge (anions) Which of the functions below are provided by proteins in the ATP synthase "machine"? - -Act as an enzyme (catalyze a reaction); Enable movement, convert chemical energy to contraction or rotation; Transport material across a membrane What kind of molecule stores the coded information that allows Lisa's cells to make insulin? - -DNA DNA is ____________, while RNA is ______________. - -double stranded; single stranded DNA contains _______________, while RNA contains ______________. - -deoxyribose sugar; ribose sugar Both DNA and RNA contain similar bases. Which bases do both types of nucleic acids contain in their nucleotides. Choose all that apply. - -Adenine, Cytosine, Guanine DNA and RNA are very important macromolecules that perform essential functions for every cell. Remember, there were many different diverse functions of proteins; however, DNA and RNA have very specific jobs. This molecule functions in storing the genetic information for the organism which is passed on to the next generation. - -DNA This molecule translates the genetic code into proteins by telling the cell the sequence of amino acids to produce the peptide (protein). - -RNA This molecule contains the "recipe" or instructions for the making of proteins. - -DNA Look at the five in the red circles in the picture above. They are representing the carbon atoms on what part of the nucleotide? - -Pentose sugar DNA maintains and copies information at a very high level of fidelity, generation after generation. What keeps the two sides of the double helix together in DNA? - -Hydrogen bonds between complementary bases Encodes human insulin, and they pass this molecule on to their own offspring so that the entire population of yeast in the vat is capable of making human insulin? - -D