Question

1. A student uses iodine to visualize cells under the light microscope. Iodine stains starch deep blue and glycogen granules dark brown.

Observation of the cells reveals the presence of cell walls, dark brown granules, mitochondria, and a prominent nucleus. If the chemical composition of the cell wall is determined, which of the following molecules would MOST likely be the major constituent?

A. cellulose

B. chitin

C. lignin

D. peptidoglycan

2. Which of the following statements is the MOST compelling argument that fungi are more closely related to animals than plants?

A. Plants have chloroplasts whereas fungi and animals cells do not.

B. Plants fix carbon dioxide from the air; fungi and animals use pre-existing organic molecules.

C. The DNA sequences of ribosomal RNA of fungi share more homology with ribosomal RNA from animals than plants.

D. Both animal and fungal cells are eukaryotic.

3. Which of the following is the MOST likely explanation for the evolutionary success of angiosperms?

A. Angiosperms have complex and successful interactions with animals leading to effective pollination and seed dispersal.

B. Angiosperms have a vascular system that allows plants to grow tall and spread spores farther.

C. Angiosperms have stomata that allow conservation of water.

D. Angiosperms developed seeds and pollen, which allow reproduction to be independent from water.

4. Observation of the development of embryos in sea stars shows the mesoderm forming pouches bulging from the archenteron to form the coelom. From this observation, you can predict that

A. the cleavage of the embryo is radial.

B. the adult animal will have bilateral symmetry.

C. the mouth forms from the first opening in the gastrula.

D. the animal is diploblastic.

Answer 1

1) A (The cell wall is mainly composed of carbohydrate rich materials. The major components of cell wall are cellulose, pectins, hemicelluloses, proteins and phenolics.)

2) A (Fungi, once considered plant-like organisms, are more closely related to animals than plants. Fungi are not capable of photosynthesis: they are heterotrophic because they use complex organic compounds as sources of energy and carbon. )

3 ) A (Those specialized flowers are able to attract organisms to help pollinate and distribute seeds)

4) C (second,” indicating that the mouth develops as a secondary structure opposite the location of the blastopore, which becomes the anus. In protostomes (“mouth first”), the first embryonic opening becomes the mouth, and the second opening becomes the anus.)