Biology Final

• Choose the best definition of a fossil.

  • a rock that contains information about an organism
  • a bone, tooth, shell, or other hard part of an organism that has been preserved
  • any trace of an organism that lived in the past
  • any part of a dead organism

  Any trace of an organism that lived in the past.
• True/False: The absence of a trait cannot be used as a synapomorphy in phylogenetic analysis; only shared derived traits that are present in the clade can be used.

  False
• Which of the following best characterizes an adaptive radiation?

  • Descendant species occupy a large geographic area.
  • A single lineage diversifies rapidly, and descendant species occupy many habitats and ecological roles.
  • Natural selection is particularly intense, because disruptive selection occurs.
  • Species recover after a mass extinction.

  A single lineage diversifies rapidly, and descendant species occupy many habitats and ecological roles.
• Which of the following is an example of homoplasy?

  • Hair in humans and fur in mice
  • Astragalus ankle bones in hippos and deer
  • Hox genes in humans and flies
  • Streamlined bodies in dolphins and ichthyosaurus

  Streamlined bodies in dolphins and ichthyosaurus
• Why are protists considered paraphyletic?

  • They include many extinct forms, including lineages that no longer have any living representatives.
  • They include some but not all descendants of their most recent common ancestor.
  • They represent all of the descendants of a single common ancestor.
  • Not all protists have all of the synapomorphies that define the Eukarya, such as a nucleus.

  They include some but not all descendants of their most recent common ancestor.
• The most important primary producers in marine ecosystems are ?___.

  Diatoms
• True/False:  Amoeboid motion is common in species with cell walls.

  False
• True/False: Amoeboid motion requires ATP and interactions between the proteins actin and myosin.

  True
• How can dinoflagellates be harmful to humans?

  • They are transmitted by mosquitoes and cause malaria.
  • They produce toxins that can be absorbed by clams and other shellfish which, when eaten by people, can lead to paralytic shellfish poisoning.
  • They cause amoebic dysentery which leads to severe diarrhea and dehydration.
  • They are transmitted by tsetse flies and cause “sleeping sickness.”

  They produce toxins that can be absorbed by clams and other shellfish which, when eaten by people, can lead to paralytic shellfish poisoning.
• What important role does lignin play in vascular plants?

  • It is the major component of the cuticle, which prevents plants from drying out.
  • It forms the outer layer of pollen grains.
  • It forms the tough, rigid cell walls of water-conducting cells.
  • It nourishes the embryo in seed plants.

  It forms the tough, rigid cell walls of water-conducting cells.
• The appearance of cuticles and stomata correlated with what event in the evolution of green plants?

  • The first upright growth forms
  • The first woody tissues
  • Growth on land
  • The evolution of the first water-conducting tissues

  Growth on land
• What is a pollen grain?

  • Male gametophyte
  • Female gametophyte
  • Male sporophyte
  • Sperm

  Male gametophyte
• True/False: Seeds contain an embryo.

  True
• True/False: Seeds contain nutritive tissue for the embryo.

  True
• True/False: Seeds consist entirely of diploid cells.

  False
• The mycelial growth habit leads to a body with a high surface-area-to-volume ratio. Why is this important?

  • Mycelia have a large surface area for absorption.
  • The hyphae that makeup mycelia are long, thin tubes.
  • Most hyphae are broken up into compartments by walls called septa, although some exist as single, gigantic cells.
  • Hyphae can infiltrate living or dead tissues.

  Mycelia have a large surface area for absorption.
• True/False: A diploid zygote is formed when a male spore fertilizes a female spore.

  False
• True/False: A mushroom is a reproductive structure that consists largely of dikaryotic cells.

  True
• The hyphae of arbuscular mycorrhizal fungi (AMF) form bushy structures after making contact with the plasma membrane of a root cell. What is the function of these structures?

  • They anchor the fungus inside the root, so the association is more permanent.
  • They increase the surface area available for the transfer of nutrients.
  • They produce toxins that protect the plant cells against herbivores.
  • They break down cellulose and lignin in the plant cell wall.

  They increase the surface area available for the transfer of nutrients.
• Which synapomorphy (shared, derived trait) distinguishes animals as a monophyletic group, distinct from choanoflagellates?

  • Multicellularity
  • Coloniality
  • Heterotrophy
  • Movement

  Multicellularity
• In a tube-within-a-tube body plan, what is the interior tube derived from?

  • Ectoderm
  • Mesoderm
  • The coelom
  • Endoderm

  Endoderm
• True/False: New major animal body plans have continued to evolve since the Cambrian about 550 million years ago.

  False
• Which of these characteristics does not apply to cnidarians?

  • Are diploblastic
  • Possess a gastrovascular cavity with one opening
  • Undergo metamorphosis
  • Have a central nervous system

  Have a central nervous system
• What is a lophophore?

  • A specialized filter-feeding structure
  • The single opening in species with a blind gut
  • A distinctive type of larva with a band of cilia
  • A synapomorphy that defines lophotrochozoans

  A specialized filter-feeding structure
• What is the function of the arthropod exoskeleton?

  • The presence of an exoskeleton has given arthropods a good fossil record because hard parts fossilize more readily than do soft tissues.
  • It has no well-established function. (Trilobites had an exoskeleton, and they went extinct.)
  • It provides protection and functions in locomotion.
  • It makes growth by molting possible.

  It provides protection and functions in locomotion
• True/False: protostome phyla successfully made the transition from water to land - Arthropoda

  True
• What is a sieve-tube element?

  • The sugar-conducting cell found in phloem
  • The widened, perforation-containing, water-conducting cell found only in angiosperms
  • The nutrient- and water-absorbing cells found in root hairs
  • The nucleated and organelle-rich support cell found in phloem

  The sugar-conducting cell found in phloem
• True/False: Tracheids and vessel elements have to be alive in order to transport water.

  False
• Which statement best characterizes primary growth?

  • It does not occur in roots, only in shoots.
  • It leads to the development of cork tissue.
  • It produces the dermal, ground, and vascular tissues.
  • It produces rings of xylem, phloem, and cork tissue.

  It produces the dermal, ground, and vascular tissues.
• A cell is placed in a solution that is hypotonic to the cell. Which of the following best describes movement of water in this situation?

  • Water will only flow into the cell.
  • Water will only flow out of the cell.
  • Water will flow into and out of the cell, but the overall net movement will be out of the cell.
  • Water will flow into and out of the cell, but the overall net movement will be into the cell.

  Water will flow into and out of the cell, but the overall net movement will be into the cell.
• What is the role of companion cells in the movement of sugars through plants?

  • They are the sites of sugar production by photosynthesis.
  • They are the sites where starch is converted to sucrose.
  • They secrete sucrose, which draws sugars through phloem under negative pressure.
  • They accumulate sucrose, which is then transferred to adjacent sieve-tube elements.

  They accumulate sucrose, which is then transferred to adjacent sieve-tube elements.
• True/False: Sieve-tube elements and vessel elements are commonly involved in the transport of phloem sap.

  False
• True/False: Nitrogen (N), phosphorus (P), and potassium (K) are common examples.

  True
• True/False: Their availability tends to limit plant growth.

  True
• Where does most nutrient uptake occur in roots?

  • At the root cap, where root tissue first encounters soil away from the zone of nutrient depletion.
  • At the Casparian strip, where ions must enter the symplast before entering xylem cells.
  • In the symplastic and apoplastic pathways.
  • In root hairs, in the zone of maturation.

  In root hairs, in the zone of maturation.
• Why are proton pumps in root-hair plasma membranes important?

  • They pump protons into cells, generating a membrane potential (voltage).
  • They allow toxins to be concentrated in vacuoles, so the toxins do not poison enzymes in the cytoplasm.
  • They set up an electrochemical gradient that makes it possible for roots to absorb cations and anions.
  • They set up the membrane voltage required for action potentials to occur.

  They set up an electrochemical gradient that makes it possible for roots to absorb cations and anions.
• Why is the presence of clay particles important in soil?

  • They provide macronutrients—particularly nitrogen, phosphorus, and potassium.
  • They bind metal ions, which would be toxic if absorbed by plants.
  • They allow water to percolate through the soil, making oxygen-rich air pockets available.
  • The negative charges on clay bind to positively charged ions and prevent them from being leached out of the soil.

  The negative charges on clay bind to positively charged ions and prevent them from being leached out of the soil.
• True/False: It results in the formation of a diploid embryo and triploid endosperm.

  True
• True/False: Both sperm involved in double fertilization form within the same pollen tube.

  True
• Which of the following does not occur during embryogenesis?

  • Formation of the radial axis
  • Production of the suspensor
  • Formation of the cotyledons and hypocotyl
  • Formation of the leaf lateral and proximal-distal axes

  Formation of the leaf lateral and proximal-distal axes