chemistry of life part 2 {module 2}

Question 1

The main classes of organic compounds are ().

Answer 1

carbohydrates, lipids, proteins, and nucleic acids

Question 2

Organic molecules are built from smaller subunits.

We call these small units building blocks or (). These () are generally carbon atoms, bonded to something else.

Answer 2

monomers

Question 3

several monomers bound together are called ()

Answer 3

polymers

Question 4

Carbohydrates consist of the elements ()

Answer 4

carbon, hydrogen, and oxygen

Question 5

All carbohydrates are made up of monomers called ()

Answer 5

monosaccharides

Question 6

Examples of monosaccharides are ()

Answer 6

glucose, fructose, and galactose

Question 7

When two monosaccharides bond together by glycosidic bonds, they form a ()

Answer 7

disaccharide

Question 8

() = glucose + fructose
() = glucose + glucose
()= glucose + galactose

Answer 8

Sucrose
Maltose
Lactose

Question 9

Many monosaccharides together form a () Examples of () are glycogen, starch, and cellulose. These take a lot longer to break down because they consist of long chains of monosaccharides. All () are made up of glucose monomers. It is the arrangement of the monomers that give the different () their structure and, therefore, function.

Answer 9

polysaccharide

Question 10

Polysaccharides are referred to as ()

Answer 10

complex carbohydrates.

Question 11

The main function of carbohydrates is ()

Answer 11

energy storage

Question 12

() is the main source of energy for all life forms

Answer 12

Carbohydrates

Question 13

Iodine solution is used to test for the presence of starch. Iodine solution will:

turn a () colour in the presence of starch.
remain () colour in the absence of starch.

Answer 13

blue-black
yellow-brown

Question 14

Schultz’s solution is used to test for the presence of cellulose. The solution will:

turn () in the presence of cellulose.
remain an () in the absence of cellulose

Answer 14

purple
orange-brown colour

Question 15

We use Benedict’s solution or Fehling’s Test to test for the presence of reducing sugars (glucose).

Both solutions contain copper sulphate and will:

turn () in the presence of reducing sugars, such as glucose.
remain () in the absence of reducing sugars.

Answer 15

red-brown
blue

Question 16

Lipids, which are your fats and oils, similar to carbohydrates contain, () Some lipids, called phospholipids, also contain ()

Answer 16

carbon, hydrogen, and oxygen.
phosphorus

Question 17

The most common type of lipid is triglycerides. Triglycerides are made up of ()

Answer 17

three fatty acids and a glycerol molecule

Question 18

elaborate the functions of lipids

Answer 18

Lipids are a very important energy reserve source. When a triglyceride is broken down, it releases glycerol and fatty acids. Glycerol can be converted into glucose, which is a great source of energy. Most of the energy released from a triglyceride, however, comes when the fatty acid chains are broken down.
Lipids help insulate the body’s organs against shock and also help with temperature regulation.
Lipids also play a vital role in the formation of cell membranes.
Some of the fatty acids contain essential nutrients, which the body does not produce itself, and, therefore, small amounts need to be consumed. Interestingly enough, nonessential fatty acids can be produced in the body from other compounds. Eating your broccoli with a little bit of butter or oil, will help with the absorption of the B vitamins into your digestive tract.
Lipids are also important in transporting and digesting and aiding in the absorption of vitamins in the body.

Question 19

Lipids can be divided into saturated and unsaturated lipids.
elaborate on this

Answer 19

Saturated lipids are mainly found in foods from animals and are solids at room temperature. Examples include: lard and butter.
Unsaturated lipids are mainly found in foods from plants and are liquid at room temperature. Examples include: olive oil, sunflower oil and margarine.

Question 20

Cholesterol is an organic chemical substance known as a ()

Answer 20

sterol

Question 21

() carries cholesterol through the body. () is a combination of fats and proteins.

Answer 21

Lipoprotein

Question 22

() have a higher proportion of cholesterol relative to protein. It is often considered “bad” cholesterol because it has been associated with heart disease, however, recent studies are starting to challenge that.

Answer 22

Low-density lipoproteins

Question 23

() are the smallest of lipoproteins. It has a higher proportion of protein relative to cholesterol and is, therefore, considered “good” cholesterol. HDL transports cholesterol to the liver (away from the cells), where it is broken down and removed as waste.

Answer 23

High-density lipoproteins

Question 24

() are made up of carbon, hydrogen, oxygen, and nitrogen, and may also contain other elements such as Iron (Fe), Phosphorus (P), and Sulphur (S).

Answer 24

Proteins

Question 25

The building blocks or monomers of proteins are (). There are about 20 () which all proteins are made up of. Nine of these () are considered essential, this is because the body cannot make them and therefore need to be consumed from our diets.

Answer 25

amino acids

Question 26

Amino acids bond together by () to form peptides. Proteins are formed from long chains of (), which fold in very specific three-dimensional shapes

Answer 26

peptide bonds

Question 27

gimme the key roles of proteins

Answer 27

Proteins found in hair, nails, skin, bone, muscle, ligaments, and tendons perform key structural and mechanical functions. Proteins are also important in cell communication and the immune system. Proteins can act as energy reserves when broken down. Certain proteins are called enzymes. We will discuss enzymes in more detail later in this lesson. Proteins are essential to our diet. A lack of protein can lead to deficiency diseases such as marasmus (caused by a general nutrient deficiency- starvation) and kwashiorkor (caused by a deficiency of protein)

Question 28

The Biuret test tests specifically for peptide bonds and will: turn () in the presence of a peptide bond remain () in the absence of a peptide bond

Answer 28

violet to purple blue

Question 29

Millon’s reagent reacts with the tyrosine amino acids (commonly found in proteins) and will: turn () in the presence of tyrosine amino acids. remain () in the absence of tyrosine amino acids

Answer 29

reddish-brown| white or cream

Question 30

() are protein molecules made up of long chains of amino acids

Answer 30

Enzymes

Question 31

Enzymes are (), this means that they speed up the rate of a reaction, without being used up themselves by the reaction. All chemical reactions require a certain minimum amount of energy in order to work. This is known as the Free energy of activation. Enzymes lower the free energy of activation levels, therefore, speeding up the rate of reaction.

Answer 31

catalysts

Question 32

() can perform anabolic reactions or catabolic reactions

Answer 32

Enzymes

Question 33

explain the difference between anabolic and catabolic reactions

Answer 33

Anabolic reactions build up many simple (small) molecules to create a complex (large) molecule. Catabolic reactions break down complex (large) molecules to create many simple (small) molecules.

Question 34

() are large organic compounds found in all cells. They are nitrogenous compounds, meaning they contain nitrogen. DNA and RNA are examples of ()

Answer 34

nucleic acids

Question 35

The building blocks of nucleic acids are ()

Answer 35

nucleotides

Question 36

() are polymers of nucleotides. They do not need to be consumed in the diet as our bodies can synthesise them using carbohydrates and amino acids

Answer 36

Nucleic acids

Question 37

DNA stands for?

Answer 37

DNA: Deoxyribonucleic acid

Question 38

() is the ‘instruction manual’ found in all your genes, which informs which proteins to be made when and where.() is found in the nucleus of every single cell in a living organism. It is also present in smaller amounts in the mitochondria and chloroplasts.

Answer 38

DNA

Question 39

RNA stands for?

Answer 39

RNA: Ribonucleic acid

Question 40

is important in transferring genetic information from our genes to form proteins. It is found in the cytoplasm and the nucleus.

Answer 40

RNA

Question 41

() contain carbon, hydrogen, and oxygen as well as nitrogen, phosphorus, and sulphur in some cases. They are needed for health and normal metabolic processes in our bodies. Most () come from plants, but plants do not require vitamins. Animals obtain () from the food they eat and absorb them into the body with the digested food.

Answer 41

vitamins