What Do Fats Steroids And Waxes Have In Common?

What do fats steroids and waxes have in common?

Less ability to dissolve in water.

Bio Exam 1 | 2023 | Biology-Lipids Test Answers

1) Main characteristic that all lipids have in common _______________.

Answer: None of them are soluble in water.

2) Which of these is NOT a lipid?

a) cholesterol

b) wax

c) steroids

d) RNA

e) phospholipid

Answer: d) RNA.

3) What do unsaturated fatty acid tails miss?

Answer:  Double Bonding.

4) It is difficult for molecules to pass through phospholipid bilayer as —————.

Answer:  Polar molecules are attracted to each other. It’s difficult for polar molecules to move from water into a membrane, and for nonpolar molecules to shift from the membrane to water. Therefore, both types of molecules struggle to pass through membranes easily.

5) Which of these is rich in unsaturated fats?

Answer: Olive oil possesses one or more bonds each having one hydrogen less, resulting in a liquid state at room temperature.

6) How are fatty acids and glycerol linked together to form fats?

Answer: In a fat molecule, each of the three carbons in the glycerol molecule is bonded to a fatty acid via an ester bond through the oxygen atom.

7) Dr. Haxton told one of his students, “To move in the bloodstream, fats need the help of phospholipids.” What would a good student say?

Answer: Indeed. Nonpolar molecules do not mix well with water. Since water repels nonpolar molecules like fats, fats are transported in particles that are enveloped by the polar segments of phospholipids and proteins.

8) In fat synthesis, ————— and fatty acids combine to make fats plus————.

Answer: Glycerol – Water.

9) A function of cholesterol that does not harm health is its role?

Answer: Cholesterol plays a vital role in the composition of animal cell membranes.

10) In the reaction that builds a fat, ————-groups react with ————-groups.

Answer: Hydroxyl; carboxyl Fatty acids supply the carboxyl groups; the hydroxyls come from glycerol.

11) What do DNA, proteins, and fats have in common?

Answer: Carbonyl groups.

12) Which of these classes of biological molecules does NOT include polymers?

A) lipids

B) carbohydrates

C) proteins

D) nucleic acids

Answer: A)Lipids.

13) Which of the following statements concerning unsaturated fats is true?

Answer: Their fatty acids contain double bonds within the carbon chains.

14) Phospholipids are most important for————-.

Answer: Stopping things from leaking out of cells. All cells use layers of phospholipids to keep stuff from passing through their outer layer.

15) What do phosphoglycerides and fats have in common?

Answer: Ester connections; Similar to fats, phosphoglycerides are formed by attaching fatty acids to glycerol through ester bonds.

16) To find the best source of phospholipids, look at ————-.

Answer: Membranes; most of a cell’s phospholipids are found in its membranes.

17) Fats vary with respect to the number of—————.

Answer: The tails commonly have carbon atoms ranging in length from 16 to 22, and can contain anywhere from 0 to 6 double bonds.

18)  The presence of many C-C and C-H bonds causes fats to be_______.

Answer: The abundance of C-C and C-H bonds renders fats nonpolar and water-insoluble. Additionally, their oxidation can release a significant amount of energy.

19) Which statement is true of phospholipids?

Answer: Their formation involves fatty acids, some of their tails possess double bonds, and they all ionize.

20) A food company hydrogenated a barrel of fat. The treatment—————–.

Answer: Hydrogenation eliminates double bonds, allowing the tails to straighten out.

21) Which fact is most important in causing phospholipids to behave as they do in water?

Answer: Water molecules form hydrogen bonds; these bonds in water push out the nonpolar tails of phospholipids, causing the molecules to arrange into a bilayer.

22) Which lipid is most amphipathic?                

Answer: A phospholipid features a highly polar (charged) head and two nonpolar tails.

23) Why that makes the fats less fluid?

Answer: The highest number of double bonds is found in the most unsaturated fats. Each double bond represents a potential site for hydrogen addition.

24) How do phospholipids interact with water molecules?

Answer: The polar heads engage with water, while the non-polar tails do not.

Similar Posts