Which of the following statements is not a tenet of modern cell theory?
A. All cells come only from preexisting cells.
B. All cells occupy space.
C. An organism's structure and all of its functions are ultimately due to the activities of its cells.
D. All organisms are composed of cells and cell products.
E. The cell is the basic structural and functional unit of life.
Answer: B
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Define the underlined terms in the following case study. An 18-month-old, F/S Siberian Husky presented to the clinic with a 3-day history of anorexia, vomiting, and diarrhea. The canine had escaped from her fenced-in yard the previous week and was picked up by animal control officers after a few days of running at large. She was placed in the local pet shelter until her owners could be reached
When she came home, the dog was depressed. She would drink, but then vomit reddish brown material, and she appeared uncomfortable to the owners. Upon taking a hx it was noted that the dog was current on her vaccinations, was on heartworm preventative, and was the only pet in the household. On PE, the dog was extremely depressed, about 7% dehydrated, and thin. Her mm were pale, and her CRT was normal. Her temperature was 104.6° F, and her heart rate and respiration rate were within normal limits. Her abdomen had gas-filled intestines, and she was uncomfortable on abdominal palpation. Blood was drawn for a CBC, chemistry panel, and parvovirus titer. Urine was collected for UA. A fecal sample was obtained both for detection of parasites and for fecal culture. The CBC showed leukopenia. The chemistry panel demonstrated hyponatremia, hypochloremia, and hypokalemia. The parvovirus titer was negative. The UA and fecal tests for parasites were negative. The fecal culture was set up and incubated overnight. Abdominal radiographs revealed diffuse thickening of the small intestinal walls with diffuse gas in the small intestine and colon, which is consistent with gastroenteritis. IV fluids and antibiotics were started on this dog. Because the fecal culture revealed salmonella, the dog was isolated from the other clinic animals and treatment continued as before. The owners were given a guarded prognosis. F/S anorexia hx PE mm CRT palpation CBC UA culture leukopenia hyponatremia hypochloremia hypokalemia radiographs diffuse gastroenteritis prognosis What will be an ideal response?
The surface osteoblasts and entombed osteocytes are connected by an extensive network of small, fluid-containing canals, called the:
a. osteons b. trabecular canals c. central canals d. lamellae e. canaliculi
How does the respiratory system contribute to osteoporosis?
A. Calcium ions released from the bones are excreted. B. Decreased estrogen levels following menopause contribute to the disease. C. Lack of exposure to sunlight reduces vitamin D production and decreases calcium absorption. D. Immune cells resist infections and release chemicals that promote tissue repair. E. Excessive smoking lowers estrogen levels, which increases bone loss.
What does structure "A" represent on the bone diagram?
A. epiphyseal lines B. cancellous bone C. epiphysis D. diaphysis E. articular cartilage