Homeostasis & Feedback
The body’s automatic tendency to maintain a constant internal environment is termed:
A. Negative feedback
B. Homeostasis
C. Physiological control
D. Phagocytosis
E. Static equilibrium
B. Homeostasis
Which of the following would not be considered a thermoregulatory adaptation in mammals or birds?
A. Ectothermy
B. Evaporative heat loss
C. Countercurrent exchange
D. Increased heat production (thermogenesis)
E. Insulation
A. Ectothermy
“Stratified columnar” is a description that would apply to which type of tissue?
A. Connective
B. Striated muscle
C. Nerve
D. Epithelial
E. Bone
D. Epithelial
Which of these planes can divide the body into equal halves?
A. Frontal (coronal)
B. Sagittal
C. Transverse
B. Sagittal
Most of the exchange surfaces of multicellular animals are lined with:
A. Connective tissue
B. Smooth muscle cells
C. Neural tissue
D. Epithelial tissue
D. Epithelial tissue
Homeostatic mechanisms:
A. Keep variables exactly at the set point
B. Help to keep a relatively constant internal environment in the body
C. Act to keep values out of the normal range
D. Usually operate by positive feedback
E. Produce most disease conditions
B. Help to keep a relatively constant internal environment in the body.
Which of the following would increase the rate of heat exchange between an animal and its environment?
A. Feathers or fur
B. Vasoconstriction near the skin
C. Blubber or a fat layer under the skin
D. Wind blowing across the body surface
E. All of the above
D. Wind blowing across the body surface
The type of muscle tissue surrounding the intestines and blood vessels is ______.
A. Skeletal muscle
B. Cardiac muscle
C. Intercalated cells
D. Smooth muscle
D. Smooth muscle
Which of these statements concerning body regions is correct?
A. The trunk region between the thorax and pelvis is the abdomen
B. The leg extends from the hip to the ankle
C. The forearm extends from the shoulder to the wrist
D. The trunk can be divided into the thorax and pelvis
E. The thorax is often subdivided superficially into four quadrants
A. The trunk region between the thorax and pelvis is the abdomen.
Of the following choices, the epithelium with the shortest diffusion distance is ______.
A. Simple squamous epithelium
B. Simple columnar epithelium
C. Pseudostratified ciliated columnar epithelium
D. Stratified squamous epithelium
A. Simple squamous epithelium
Negative-feedback mechanisms:
A. Are not homeostatic
B. Are rare in healthy individuals
C. Respond by making deviations from normal even higher
D. Are counteracted by most medical therapy
E. May have a receptor, a control center, and an effector
E. May have a receptor, a control center, and an effector.
In an endotherm, which of the following homeostatic processes would be produced by a sudden and prolonged decrease in ambient temperature?
A. Decreased oxygen uptake
B. Decreased muscular activity
C. Decreased blood flow to the skin surface
D. Decreased rate of internal metabolic processes
E. All of the above
C. Decreased blood flow to the skin surface
Cardiac muscle cells are both ______.
A. Striated and interconnected by intercalated disks
B. Smooth and under voluntary control
C. Striated and under voluntary control
D. Smooth and under involuntary control
A. Striated and interconnected by intercalated disks
Coronal (frontal) planes divide the body into ______ portions.
A. Right and left
B. Anterior and posterior
C. Superior and inferior
D. Dorsal and ventral
E. Both B and D
E. Both B and D
Compared with a smaller cell, a larger cell of the same shape has ______.
A. Less surface area
B. Less surface area per unit of volume
C. A smaller average distance between mitochondria and the external source
D. A smaller cytoplasm-to-nucleus ratio
E. Equal surface area per unit of volume
B. Less surface area per unit of volume
Once labor begins in childbirth, contractions increase in intensity and frequency, causing more contractions to occur until delivery. The increasing labor contractions of childbirth are an example of which type of regulation?
A. Positive feedback
B. Negative feedback
C. Feedback inhibition
D. Enzymatic catalysis
A. Positive feedback
A countercurrent flow system between substance A and substance B:
A. Maximizes the exchange by having A and B flow in the same direction
B. Minimizes the exchange by having A and B flow in the same direction
C. Maximizes the exchange by having A and B flow in opposite directions
D. Minimizes the exchange by having A and B flow in opposite directions
E. None of the above
C. Maximizes the exchange by having A and B flow in opposite directions.
Connective tissues typically have ______.
A. Little space between the membranes of adjacent cells
B. The ability to transmit electrochemical impulses
C. The ability to shorten upon stimulation
D. Relatively few cells and a large amount of extracellular matrix
D. Relatively few cells and a large amount of extracellular matrix
Which of the following statements comparing the Endocrine system (ES) and Nervous system (NS) signaling is true?
A. Hormones are fast acting, but effects often short-acting
B. In ES signaling, all body cells can respond to the circulating hormone
C. Nerve impulses can be received by all cell types within the body
D. The NS transmits a signal to a target cell via a specific pathway
E. ES transmission compared to NS transmission is very fast
D. The NS transmits a signal to a target cell via a specific pathway.
An evolutionary adaptation that enables animals with more complex body designs to ensure sufficient exchange with their environment:
A. Reduced plasma membrane surface area
B. Insulation
C. Highly folded internal surfaces
D. Increased body size
E. Increased cell volume
C. Highly folded internal surfaces
When the body’s blood glucose level rises, the pancreas secretes insulin and, as a result, the blood glucose level declines. When the blood glucose level is low, the pancreas secretes glucagon and, as a result, the blood glucose level rises. Such regulation of the blood glucose level is the result of ______.
A. Catalytic feedback
B. Positive feedback
C. Negative feedback
D. Protein-protein interactions
C. Negative feedback
Four students carried out studies to determine whether a newly discovered animal was an ectotherm or endotherm. Each student made one observation and one conclusion. Which is the correct conclusion based on the observation?
A. It was not a mammal—the animal is an ectotherm
B. Its body temperature is 37°C—the animal is an endotherm
C. Its temperature remained stable when the temperature of the cage decreased—the animal is an endotherm
D. Its temperature and metabolism increased when the cage temperature increased—the animal is an ectotherm
C. Its temperature remained stable when the temperature of the cage decreased—the animal is an endotherm.
Blood is best classified as connective tissue because ______.
A. It is a part of the vascular system
B. It contains plasma, salt, water, and protein
C. Its cells are separated from each other by an extracellular matrix
C. Its cells are separated from each other by an extracellular matrix.
Much of the coordination of vertebrate body functions via chemical signals is accomplished by the ______.
A. Respiratory system
B. Endocrine system
C. Integumentary system
D. Excretory system
B. Endocrine system
Which of the following is a true statement about body size and physiology?
A. The amount of food and oxygen an animal requires and the amount of heat and waste it produces are inversely proportional to its mass
B. The rate at which an animal uses nutrients and produces waste products is independent of its volume
C. Small and large animals face different physiological challenges because an animal’s body mass increases cubically while its surface area increases as a squared function
D. The wastes produced by an animal double as its volume doubles and triple as its surface area triples
C. Small and large animals face different physiological challenges because an animal’s body mass increases cubically while its surface area increases as a squared function.