Intro to BioChem Exam 2

End of Module Quizzes 3 and 4

A glycosidic link is chemically an _____.

Ether

Which of the following is not a homoglycan?

Heparin

The three most common homoglycans found in nature are cellulose, starch and __________.

Glycogen

Glycogen is:

Main carbohydrate reserve of animals

How many stereoisomers are possible for an aldohexose

16

Both glycogenesis and glycogenolysis are controlled primarily by the interplay between the two hormones insulin and ________.

Glucagon

The presence of which of the following molecules indicates that the cell has sufficient energy reserves?

ATP and Citrate

In glycolysis ________ moles of NADH are produced per mole of glucose consumed

2

Cellulose is indigestible to most animals because:

Animals lack the enzymes required to hydrolyse the b links of the cellulose

Glycoproteins lack which of the following groups typically found in proteoglycans?

Uronic acids and Sulfate groups

The accumulation of AGEs is linked to which of the following diseases?

Atherosclerosis

Arthritis

Diabetes

All of the above are correct

Under stressful conditions epinephrine is released from the adrenal medulla. The release of epinephrine has which of the following effects on glucose metabolism?

Glycogenolysis is stimulated

Glycogenesis is inhibited

Adenylate cyclase is activated 

All of the above are correct

Fructose-2,6-bisphosphate

Is an indicator of high cellular glucose concentration

Which of the following polysaccharides is known to bind the largest amount of water?

Heparin

Glycoconjugates result from the covalent linkage of carbohydrate to proteins or _________

Lipids

The name of this sugar is...

D-Galactose

An enzyme family called the _________ catalyzes the phosphorylation of hexoses in the body.

Hexokinases

Carbohydrate is thought to enhance the stability of protein molecules by:

Protecting the underlying protein from the action of proteolytic enzymes

Reaction of an amino acid with C1 of a cyclic aldose produces which of the following linkages?

Glycosidic

The preferred energy source of the brain is __________.

Glucose

Which of the following carbohydrates is a nonreducing sugar?

  Sucrose

The binding of insulin to receptors on the surface of muscle cells stimulates which of the following processes

Glycogenesis

Lactose intolerance arises from

The inability of intestinal enzymes to cleave the lactose

In glycoproteins carbohydrate is most often linked to threonine, asparagine or __________.

Serine

Which of the following is required for the conversion of UDP-glucose to glycogen?

Glycogen synthase and Branching enzyme

Name this sugar....

D-Fructose

Which of the following yields N-acetyl-D-glucosamine on hydrolysis.

Chitin

Which of the following sugars contains a b-1,4-linkage?

Cellulose

The most abundant organic substance on earth is ______

Cellulose

FeS1, cyta, HemeB4, FADH2, cyt1A1, FeS2, UQ, cytb, O₂

How many malonyl molecules will need to be made to synthesize a 20 carbon long fatty acid?

9

Plasma lipoproteins transport _______ through the blood from one organ to another.

Triacylglycerols

Phospholipids

Cholesteryl esters

All of the above are correct

During the production of mevalonate, a necessary molecule in cholesterol biosynthesis,  reducing molecules are needed.  Which reducing molecule(s) are used during the formation of mevalonate?

NADPH

Acetyl CoA that is consumed by the citric acid cycle is produced from which of the following biochemical pathways?

 

Glycolysis and Fatty acid oxidation

Lipolysis is used to

Degrade triacylglycerols

Glycerol from the hydrolysis of triacylglycerols is transported by the blood to the ____

Liver

Energy requiring transport mechanisms include

Primary active transport

Phospholipids are

Structural components of membranes and Surface active agents

The conversion of acetyl-CoA to malonyl-CoA is inhibited by ________.

Glucagon

Epinephrine

Palmitoyl-CoA

All of the above are correct

Phospholipids are

Structural components of membranes and Surface active agents

In addition to the prostaglandins and leukotrienes the autocrine regulators include:

Thromboxanes

Saturated fatty acids containing up to 16 carbon atoms are assembled in ________.

Cytoplasm

How many moles of NADH would be made if two moles of glucose proceeded all the way through aerobic respiration? (stopping after completing the citric acid cycle).  Only fill in whole numbers for your answer. 

 

Total number of NADH developed entered as a whole number = [____]

20

The role of very low density lipoproteins is

Transporting of lipids from liver to tissues

Cholesterol is a precursor of _________.

Aldosterone

Cortisol

Testosterone

Estrogen

All of the above are correct

_________ are the principal transporters of cholesteryl esters to tissues.

Low density lipoprotein

The myelin sheath

Surrounds nerve cell axons and Facilitates nerve impulse transmission

Which of the following molecules are a precursor to cholesterol synthesis?

squalene

Acetyl CoA that is consumed by the citric acid cycle is produced from which of the following biochemical pathways?

 Glycolysis and Fatty acid oxidation

What is the systematic name of a fatty acid with the following abbreviation?

16:1cD9

cis-9-Hexadecenoic

Plasma lipoproteins transport _______ through the blood from one organ to another.

 

Triacylglycerols

Phospholipids

Cholesteryl esters 

All of the above are correct

A membrane’s fluidity is largely determined by the percentage of

Unsaturated fatty acids

When triglycerides are mobilized from adipose tissue and used as fuel in other cell types.  What is a common role for the glycerol molecules that are generated during this process?

They can enter glycolysis

Which of the following is not a function of phospholipases?

 Energy storage

Prostaglandins are involved in _________.

Ovulation

Inflammation

Digestion

All of the above are correct

The basic structure of biological membranes is a consequence of the physical properties of _______.

Phospholipids

Which of the following fatty acids have the highest melting point considering that all double bonds are cis double bonds?

The top image

Which of the following is not a function of lipids

Energy storage

Components of biological membranes

Insulation

Source of acetyl-CoA

All of the above are functions of lipids

Prostaglandins are involved in _________.

Ovulation

Inflammation

Digestion

All of the above are correct

Have a double bond six carbon atoms from the methyl end of the chain