Use the following description to answer the question(s) below

The cycads, a mostly tropical phylum of gymnosperms, evolved about 300 million years ago and were dominant forms during the Age of the Dinosaurs. Though their sperm are flagellated, their ovules are pollinated by beetles. These beetles get nutrition (they eat pollen) and shelter from the microsporophylls. Upon visiting megasporophylls, the beetles transfer pollen to the exposed ovules. In cycads, pollen cones and seed cones are borne on different plants. Cycads synthesize neurotoxins, especially in the seeds, that are effective against most animals, including humans.

Which feature of cycads distinguishes them from most other gymnosperms?
1. They have exposed ovules.
2. They have flagellated sperm.
3. They are pollinated by animals.
A) 1 only
B) 2 only
C) 3 only
D) 2 and 3
E) 1, 2, and 3


Answer: D

Biology & Microbiology

You might also like to view...

The microtubules that form the mitotic spindle grow out from the centrosome. Where would you expect to find the plus (fast growing) end of a spindle microtubule?

A. at the centrosome B. away from the centrosome C. at the kinetochore D. Answers b and c are both correct.

Biology & Microbiology

Which of the following is not evidence for the rearrangement mechanism in the immune system evolving from transposons?

A. Transposases have sequence homology to immunoglobin genes. B. The mechanism for RAG1 and RAG2 resembles the transposition mechanism. In the reaction, an intermediate is formed transiently that has hairpins at the ends of the sequences being removed. C. The fragment deleted from between the V segments during rearrangement can be inserted into DNA by RAG1 and RAG2 in vitro. D. The fragment deleted from between the V segments during rearrangement has structural similarity to transposons. E. All of the choices given provide evidence.

Biology & Microbiology

What is the primary driving force for the binding of oxygen to hemoglobin?

A) PO2 B) PCO2 C) pH D) temperature E) 2,3-bisphosphoglycerate (2,3-BPG)

Biology & Microbiology

What do sharks have in common with goldfish?

A) Opercula B) A lateral line system C) Electrosensors D) A cartilaginous skeleton

Biology & Microbiology