Excretory and Digestive Systems Practice Test Review

Flashcards covering human excretory and digestive systems, metabolic stages, enzymes, and associated organs.

What biochemical pathway does the liver utilize to convert highly toxic ammonia into milder urea?

Ornithine Cycle

According to cellular toxicity levels, urea is approximately how many times less toxic to human cells than raw ammonia?

$100,000$ times

Why is the right kidney positioned slightly lower than the left kidney in the abdominal cavity?

To accommodate the large size of the liver directly above it

At what volume of urine inside the urinary bladder is the initial "gotta go" micturition signal sent to the brain?

$150\,\text{mL}$ to $200\,\text{mL}$

Which nephron structure dips down into the renal medulla to save valuable water and sodium salts for body hydration?

Loop of Henle

Which mathematical formula correctly represents the net urinary excretion process?

$$\text{Excretion} = \text{Filtration} - \text{Reabsorption} + \text{Secretion}$$

What specific pigment chemical gives normal urine its characteristic yellow color?

Urochrome

Who proposed the famous "Lock and Key" model of enzyme-substrate interaction in $1894$?

Emil Fischer

How does hydrochloric acid (HCl) function in the gastric chemical digestion of proteins?

It turns an inactive substance into active pepsin

Which enzyme secreted in pancreatic juice is responsible for converting fats into fatty acids and glycerol?

Steapsin

Following nutrient absorption in the small intestine, where do fatty acids and glycerol travel immediately after leaving the epithelial cells?

Lacteal vessels of the lymphatic system

What liver-released waste pigment is eliminated via the intestines, giving feces its normal brown color?

Bilirubin

What is the name of the lubricated, chewed ball of food created by the action of the teeth, tongue, and saliva in the oral cavity?

Bolus

During deglutition (swallowing), which structure closes over the trachea to prevent food from entering the respiratory tract?

Epiglottis

What specific center in the brain receives signals when the urinary bladder fills and needs to be emptied?

Micturition Center

At the beginning of the large intestine, what blind pocket features the small worm-like appendix?

Caecum (Cecum)

Besides cooling the body through evaporation, sweat glands excrete water, excess salts, and trace amounts of which metabolic waste?

Urea

Which intestinal enzyme works as the final protein-digesting enzyme to yield free amino acids?

Erepsin

What double-walled cup-like structure surrounds the glomerulus within the nephron?

Bowman's Capsule

Where is blood containing newly absorbed monosaccharides (sugars) and amino acids routed immediately upon leaving the intestinal capillaries?

To the liver via the hepatic portal vein

What are the Five (5) Primary Excretory Organs of the human body?

Kidney, Liver, Lungs, Skin, and Intestines

What are the Three (3) Major Enzymes present in pancreatic juice?

Steapsin, Trypsin, and Amylopsin

What are the Two (2) Stages of metabolism?

Anabolism and Catabolism

What is the microscopic functional filtering unit of the kidney, with roughly one million located in each kidney?

Nephron

What term describes rhythmic, wave-like muscular contractions that move food along the alimentary canal?

Peristalsis

What is the soupy, highly acidic liquid formed in the stomach when food mixes with gastric juices?

Chyme

Which metabolic stage involves building up new cells, tissues, and biochemical materials?

Anabolism

What pair of thin muscular tubes, measuring $10$ to $12\,\text{inches}$ long, carry urine from the kidneys down to the bladder?

Ureters

What digestive fluid produced by the liver and stored in the gallbladder neutralizes acidic chyme and emulsifies fats?

Bile

What are the microscopic, finger-like projections lining the inner mucosal wall of the small intestine that increase surface area for nutrient absorption?

Villi

What enzyme present in saliva (also known as salivary amylase) begins the chemical breakdown of carbohydrates in the mouth?

Ptyalin

What is the process by which cells absorb and utilize digested nutrients carried by the bloodstream for cellular repair, growth, and energy production?

Assimilation