Laboratory Review 3- Chemical Composition of Cells

Steroids are derived from

Cholesterol

Gives a standard by which to tell if the substance being tested is present in an unknown sample. This is known as?

Control samples

Starch is a protein, true or false?

False

Four chains of polypeptide form what protein?

Hemoglobin

Which transport protein transports oxygen throughout the body?

Hemoglobin

Bonds are broken and water is added in what type of reactions?

Hydrolysis Reactions

What kind of reaction adds water to break large biomolecules into subunits?

Hydrolysis reaction

What kinds of biomolecules are insoluble in water but soluble in alcohol or either?

Lipids

If you test an unknown substance with the buret reagent and it turns purple what is present?

Protein

If the sample of water you test with biuret reagent turns purple, what should you conclude about the results of your experiment? Explain.

Protein is present

Biuret reagent turns what color for proteins?

Purple

Amino aids differ by and have varying sizes, shapes, and chemical activities?

R groups

Maltose has two sugar units. Also known as?

A disaccharide

Glucose has one sugar unit. Also known as?

A monosaccharide

A chin of two or more amino acids is called?

A peptide

A very long chain of amino acids is called?

A polypeptide

Glycogen, starch, and cellulose are made up of chains of glucose units. Also known as?

A polysaccharide

A polysaccharide contains large numbers of glucose molecules joined together. A polysaccharide is known as?

A starch

Proteins are made up of?

Amino acids

What are proteins made up of?

Amino acids

Enzymes are composed of what type of organic molecule?

Amino acids, proteins

Which enzyme speeds up the breakdown of starch in the mouth and small intestine?

Amylase

What can cause a fat to disperse in water?

An emulsifier

If you test a sample of potato with the buret reagent, what do you expect the results to be?

Become dark blue

If you want to test a sample to see if glucose is present, what reagent should you use?

Benedicts/glucose solution

What must be present to successfully break down fats during digestion?

Bile

Strong solution of sodium or potassium hydroxide that changes color in the presence of proteins or peptides?

Biuret Reagent

What blue solution tests for proteins?

Biuret reagent

If starch is present, what color will the iodine turn?

Black-Blue

If protein is present, iodine solution becomes what color?

Black-blue

If a solution contains a large amount of glucose, what color will the Benedict's reagent become?

Blue

In the presence of starch, iodine solution (yellow-ish brown) reacts chemically with starch to form what color?

Blue-black

What kind of bond forms during a dehydration synthesis reaction involving two amino acids?

Dipeptide

What kind of protein is lactose, the biomolecules that speeds up the breakdown of lactose?

Enzyme

Proteins that speed chemical reactions are called?

Enzymes

After enjoying a meal of fish and chips, you notice your shirt has an oily stain on it. Why won't the oily stain come out when you dab at it with just water?

Fats are non polar, do not mix with water

Why do experimental procedure include control samples?

Gives a standard by which to tell if the substance being tested is present in an unknown sample

Animals store glucose as?

Glycogen

A single chain of polypeptide forms what protein?

Insulin

Which regulatory protein regulates the amount of glucose in blood?

Insulin

What solution is used in the presence of starch?

Iodine solution

Which structural protein is found in hair?

Keratin

Which structural protein is found in muscle?

Myosin

When molecules have no charged groups or atoms, they are considered?

Nonpolar

If maltose undergoes hydrolysis, what subunits result?

Nucleotides

A chain of two or more amino acids is called a?

Peptide

Phospholipids have the same structure as fats, except that in place of the third fatty acid there is a?

Phosphate group

Biuret reagent turns what color for peptides?

Pinkish-purple

What is the name used for plant fats?

Plant fats

Where are phospholipids found within a cell?

Plasma membrane

When molecules have charged groups or atoms, they are considered?

Polar

A very long chain of amino acids are called?

Polypeptide

If amylase is added to a sample of potato and you test it with Benedict's reagent 10 minutes later, what do you expect the results of the test to be? Justify your reply.

Positive, starch is broken down in glucose

As what molecules do plants store glucose

Starch

Plants store glucose as?

Starch

Sex hormones like estrogen and testosterone are known as?

Steroids

Carbohydrates include

Sugars and molecules that are chains of sugars

If starch is present, iodine solution becomes what color?

Yellowish brown