Describe the problems associated with a terrestrial existence and some of the adaptations of some animals for dealing
with these problems. What will be an ideal response?
Concepts to Consider: The main problem with living on land is desiccation. Many animals
have a body covering or integument that limits water loss. In addition, an efficient excretory
system and the location of the respiratory system deep within the body also limit water loss.
Another problem associated with a terrestrial existence is the effects of gravity, since there is no water to buoy the bodies of terrestrial organisms. Some animals overcome this problem by
having small bodies or having strong supporting structures such as exoskeletons or
endoskeletons. A third problem with living on land is how to join sperm and eggs. This can
be overcome by having internal fertilization (copulation). Finally, eggs that are released from
terrestrial animals may desiccate if they are not protected. One means of protection is
surrounding eggs with a tough covering that prevents water loss, or storing eggs inside the
body of the mother, surrounded by the body fluids of the parent.
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Match the item to its definition.
A) collection of dendrites B) collection of axons C) discontinuous insulation of the dendrite D) process that sends electrical signals toward from the cell E) excess of positive charge within the cell and excess of negative charge outside the cell F) discontinuous insulation of the axon G) region of nerve cells where the myelin sheath is incomplete H) gap between adjacent nerve cells I) excess of negative charge within the cell and excess of positive charge outside the cell body J) process that sends electrical signals away from the cell body 1) dendrite 2) nerve 3) myelin sheath 4) nodes of Ranvier 5) resting membrane potential 6) axons 7) synapse
Which statement best describes the difference between cell division in plant and animal cells?
a. In animal cells but not plant cells, cytokinesis is accomplished by formation of a cleavage furrow. b. In plant cells but not animal cells, cytokinesis is accomplished by formation of a cleavage furrow. c. In plant cells, centrosomes have an important role in spindle formation, while in animal cells centrosomes do not function during cell division. d. In animal cells, replication of chromosomes occurs during interphase, while in plant cells replication occurs when the nuclear envelope disintegrates. e. Animal cells divide via the cell cycle whereas plant cells divide by binary fission.
Osteoporosis is when what happens?
What will be an ideal response?
____ arises as a result of directional selection on species that share a limited resource; the result is minimized competition.
A. Resource partitioning B. Inclusive competition C. Intraspecific cooperation D. Primary succession E. Secondary succession