What causes RDS (respiratory distress syndrome) in premature babies?
A. Bronchioles are constricted due to excess production of mucus.
B. There is insufficient production of surfactant.
C. Muscles associated with respiration are not strong enough to expand the thorax.
D. The lungs have not yet produced adequate numbers of alveoli for efficient gas exchange.
E. Respiratory centers of the brain are not functional until late in the fetal stage.
Answer: B
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The folds of the surface of the cerebellum
A) are called folia and are less prominent than the cerebral folds. B) form a network of blood vessels over the brain. C) consist of axons and dendrites of neurons. D) are bathed in spinal fluid. E) are called sulci.
Which of the following neurotransmitters are used in virtually all of the inhibitory synapses found in the spinal cord?
a) gamma aminobutyric acid (GABA) and acetylcholine b) gamma aminobutyric acid (GABA) and glycine c) epinephrine and norepinephrine d) serotonin and melatonin e) glutamate and aspartate
All sensory information, except for smell and proprioception, passes through this area of the brain, called the ________
A) thalamus B) hypothalamus C) frontal lobe D) basal nuclei
Which statement is true concerning the genetic code?
A)Protein synthesis plays a small but important part in the metabolic machinery of the cell. B)DNA serves as the master blueprint for the synthesis of carbohydrates, lipids and proteins. C)DNA is said to specify only the structure of protein. D)The chemical structure of cells is primarily determined by lipids while the physical nature of cells is determined by proteins.