Which of the following is not usual result of exercise?
increase in the number of myofibrils within the muscle cells
The vital centers for control of heart rate, respiration, and blood pressure are located in the?
In bone formation, a deficiency of growth hormone will cause
decreased proliferation of the epiphyseal plate cartilage
The numbers listed represent the first, second, and third energy levels, respectively. On this basis, which of the following is an unstable or reactive atom?
Which statement is not true concerning characteristics of life?
Each organ system is isolated from all other body systems
Which of the following is a principle of the fluid mosaic model of cell membrane structure?
Phospholipids form a bilayer that is largely impermeable t water-soluble molecules
Which one of the following planes would result in sections containing both the lungs and the heart?
1 and 2
In the left cerebral hemisphere we possess areas of functioning in speech. The area involved in comprehension of the written and spoken language is called:
A rapid repetitive series of threshold stimuli leading to a single, fused, sustained contraction is:
sumation of contraction
One of the functional characteristics of life is irritability. This refers to:
sensing changes in the environment and then reacting or responding to them.
Which of the following statements is true concerning feedback mechanisms?
Negative feedback mechanisms work to prevent sudden severe changes within the body
Smooth muscle is significantly different from striated muscle in several ways. Which of the following is true?
Smooth muscle shortens and stretches to a greater extent than does striated muscle
A neuronal circuit that concentrates or directs a large number of incoming impulses to a rather small number of neurons is called:
The role of acetylcholinestrerase is to:
destroy ACh a brief period after its release by the axonal endings
When Acetylcholine diffuses across the synaptic cleft and binds to receptors on the folded sarcolemma it initally causes____ channels to open in the sarcolemma.
A contraction in which the muscle changes in length with the same tension applied to it is called:
An individual accidentally transected the spinal cord betweenT1 and L2. This would result in:
Smooth muscles that act like skeletal muscles but are controlled by autonomic nerves and hormones are:
The universal loss of bone mass seen in the skeleton, which begins about the age of 40:
reflects an imbalance in the bone remodeling process
Select the correct statement about synapses
The synaptic cleft prevents an impulse from being transmitted directly from one neuron to another
Which statement is the most correct regarding transcription/translation?
The nucleotide sequence in a tRNA anticodon is an exact copy of the DNA triplet that coded for it except that uracil is substituted for thymine
Which one of the following statements is correct regarding diffusion?
The greater the concentration gradient, the faster the rate of diffusion
Chromosomal centromeres split and chromosomes migrate to opposite ends of the cell in which of the following?