anatomy exam 4

Which of the following is not a phase of deglutition? A. laryngeal B. esophageal C. pharyngeal D. buccal

A

Distinguish between chemical digestion and absorption.

Chemical digestion involves the breakdown of food, whereas absorption involves the movement of nutrients across the digestive epithelium into the interstitial fluid.

All of the following are true of beta-oxidation except that A. it requires coenzyme A, NAD, and FAD. B. it occurs in the mitochondria. C. it ultimately yields large amounts of ATP. D. lipids are converted into glycogen molecules. E. fatty acids break down into acetyl-CoA that enter the citric acid cycle.

D

Choose the correct statement regarding glycolysis. A. It occurs in the mitochondrion. B. NAD accepts carbon atoms that can be transferred to mitochondria. C. It is an aerobic process that breaks down a six-carbon glucose molecule into two three-carbon molecules of pyruvate. D. There is a net gain of two ATP molecules for each glucose molecule.

D

________ carry excess cholesterol from peripheral tissues to the liver.

High-density lipoproteins (HDLs)

When and how do ketone bodies form?

during the postabsorptive state when lipids and amino acids are broken down by the liver

The process of synthesizing glucose from non-carbohydrates is called

gluconeogenesis.

Why can smooth muscle contract over a wider range of resting lengths than skeletal muscle?

in smooth muscle the actin and myosin are more loosely organized

Where does most nutrient absorption occur?

in the small intestine, primarily in the jejunum

Starting at the mouth, identify the major organs of the digestive tract.

oral cavity (mouth), pharynx, esophagus, stomach, small intestine, large intestine

Chief cells secrete

pepsinogen

Waves of muscular contractions that propel the contents of the digestive tract are called

peristalis

The ability of smooth muscle to contract over a wide range of lengths is called ________, while its normal background level of activity is known as ________.

plasticity; tone

When the body is relying on internal energy reserves to continue meeting its energy demands, it is in the ________ state.

postabsorptive

The enzyme pepsin digests

proteins

Glycolysis breaks down glucose into what?

pyruvate

The function of the citric acid cycle is to

remove hydrogen atoms from organic molecules and transfer them to coenzymes.

Resting energy expenditure is most directly determined by monitoring

respiration.

The ________ mechanically digests ingested food.

stomach

The oral mucosa has ________ epithelium.

stratified squamous

Large blood vessels and lymphatics are found in the

submucosa

Which layer of the digestive tract has a dense irregular connective tissue that surrounds the muscularis mucosae?

submucosa

Approximately ________ liters of fluid are secreted and reabsorbed into the peritoneal cavity each day.

7

All of the following is true of the electron transport system except A. is found on the inner mitochondrial membrane (the cristae). B. produces energy that supports the synthesis of ATP. C. is found on the outer mitochondrial membrane. D. receives electrons from coenzymes. E. electrons are eventually accepted by oxygen with the formation of water.

C

Compare catabolism and anabolism.

Catabolism is the breakdown of large molecules into smaller ones, whereas anabolism is buildup of large molecules from smaller building blocks.

Explain the role of glycogen in cellular metabolism.

It serves as an intracellular glucose reserve.

What molecule forms the common substrate for the citric acid cycle?

acetate ion

What is a nutrient pool?

an accessible source of substrates for a cell

After food and gastric juices combine, the gastric contents are referred to as

chyme

The ________ is a double sheet of peritoneal membrane that suspends the visceral organs and carries nerves, lymphatics, and blood vessels.

mesentery

Carbohydrate digestion begins in the

mouth

In oxidative phosphorylation, energy for the synthesis of ATP is directly obtained from the

movement of hydrogen ions through channels in the inner mitochondrial membrane.

Name the four layers of the digestive tract beginning from the lumen of the digestive tract.

mucosa, submucosa, muscular layer, serosa

Gastric pits are

openings into gastric glands

In amino acid metabolism, identify the processes by which the amino group is removed.

transamination or deamination

In transamination, the amino group of an amino acid is ________, yielding a different amino acid.

transferred to another molecule

During lipolysis,

triglycerides are broken down into glycerol and fatty acids.

The conversion of ammonia into a less toxic substance produces

urea.

What type of muscle cells are arranged in sheets or layers, with adjacent muscle cells electrically connected by gap junctions and mechanically connected by dense bodies?

visceral smooth muscles