Multiple ChoiceIn what order would you pass through tissues when moving from the pith to the epidermis in a plant possessing secondary vascular tissue?
Multiple ChoiceA vandal killed a historic oak tree on the village green by girdling it with a chain saw. He cut through the bark and into the sapwood all the way around the tree. Why did the tree die?
Open QuestionWhat is a sieve-tube element?a. the sugar-conducting cell found in phloemb. the widened, perforation-containing, water-conducting cell found only in angiospermsc. the nutrient- and water-absorbing cell found in root hairsd. the nucleated and organelle-rich support cell found in phloem
Open QuestionEvaluate the following statements regarding tracheids and vessel elements. Select True or False for each statement.T/F Both tracheids and vessel elements are specialized for water conduction.T/F Both tracheids and vessel elements have pits.T/F Vessel elements have perforation plates but tracheids do not.T/F Tracheids and vessel elements have to be alive in order to transport water.
Open QuestionSplicing begins:a. as transcription occurs.b. after transcription is complete.c. as translation occurs.d. after translation is complete.
Open QuestionWhat is the role of companion cells in the movement of sugars through plants?a. They are the sites of sugar production by photosynthesis.d. They are the sites where starch is converted to sucrose.c. They secrete sucrose, which draws sugars through phloem under negative pressure.d. They accumulate sucrose, which is then transferred to adjacent sieve-tube elements.
Open QuestionCompared with mRNAs that have a cap and tail, predict what will be observed if a eukaryotic mRNA lacked a cap and poly(A) tail.a. The primary transcript would not be processed properly.b. Translation would occur inefficiently.c. Enzymes on the ribosome would add a cap and poly(A) tail.d. tRNAs would become more resistant to degradation.