biology 1406
Some plants called lithops grow in the South African desert and look like stones. How were scientists able to determine they are living organisms?
Lithops are autotrophic. They show growth and reproduction.
Does the statement lend itself to investigation using the scientific method? In other words, is the hypothesis falsifiable (can be proven false)? Is macaroni and cheese tastier than broccoli soup? Are hummingbirds attracted to the color red? Is the moon made out of green cheese? Is plagiarism dishonest?
Questions 1 and 4 are subjective and cannot be disproven using scientific method. Questions 2 and 3 can be tested using scientific method.
Compelling evidence for the theory of evolution comes from many scientific disciplines. Suppose paleontologists discovered a fossil of an extinct mammal that lived high in the Rocky Mountains. They write a scientific paper comparing the mammal to present-day mammals. Which of the following would you expect their comparison data to show?
The extinct mammal more closely resembles present-day mammals that live in the North American prairies than present-day mammals that live high in African mountains.
Consider the levels of organization of the biological world and place each of these items in order from smallest level of organization to most encompassing: skin cell, elephant, water molecule, planet Earth, tropical rainforest, hydrogen atom, wolf pack, liver.
hydrogen atom, water molecule, skin cell, liver, elephant, wolf pack, tropical rainforest, planet Earth
Which of the following domains contain prokaryotes? 1.Archaea 2.Bacteria 3.Eukarya
1 and 2
Decide if each of the following is an example of inductive or deductive reasoning. 1.All flying birds and insects have wings. Birds and insects flap their wings as they move through the air. Therefore, wings enable flight. 2.Insects generally survive mild winters better than harsh ones. Therefore, insect pests will become more problematic if global temperatures increase. 3.Chromosomes, the carriers of DNA, separate into daughter cells during cell division. Therefore, DNA is the genetic material. 4.Animals as diverse as insects and wolves all exhibit social behavior. Therefore, social behavior must have an evolutionary advantage for humans.
1- Inductive, 2- Deductive, 3- Deductive, 4- Inductive
In the phylogenetic tree shown, which organism is most distantly related to 2?
5
Which of the following structures is conserved in all living organisms and points to a common origin?
All living organisms store genetic material in DNA/RNA.
Compare the way in which the present-day theory of evolution developed with the basic principles of the scientific method. What parallels do you see? Explain.
Both Darwin and Wallace made reproducible observations, drew conclusions based on these observations, and communicated their results.
In which domain would a fish be classified? Why?
Eukarya, because fish are multicellular.
Evolution occurs slowly and gradually. Which statement is an appropriately evidence-based refinement of the statement above?
Evolution occurs slowly and gradually, but it can also occur rapidly. In addition to gradual evolution of species, rapid evolutions are evidenced in drug-resistant strains of bacteria and other disease-causing organisms.
The human immunodeficiency virus (HIV) reproduces very quickly. A single virus can replicate itself a billion times in one 24-hour period. In a hypothetical treatment situation, a patient's HIV population consists entirely of drug-resistant viruses after just a few weeks of treatment. How can this treatment result best be explained? How does this explanation illustrate that evolution is an ongoing process?
The non-resistant viruses died, and the resistant ones survived and rapidly reproduced. This illustrates evolution as an ongoing process because the change in the HIV population is the result of natural selection.
In the example below, the scientific method is used to solve an everyday problem. Order the scientific method steps (numbered items) with the process of solving the everyday problem (lettered items). Based on the results of the experiment, is the hypothesis correct? If it is incorrect, propose some alternative hypotheses. Scientific Method Everyday process1 ObservationAThere is something wrong with the electrical outlet. 2QuestionBIf something is wrong with the outlet, my coffeemaker also won't work when plugged into it. 3Hypothesis (answer)CMy toaster doesn't toast my bread. 4PredictionDI plug my coffee maker into the outlet. 5ExperimentEMy coffeemaker works. 6ResultFWhat is preventing my toaster from working?
The original hypothesis is incorrect. Alternative hypothesis includes that toaster wasn't turned on.
What is the importance of the nodes seen on the illustration of the phylogenetic tree seen here?
They show points during evolution when ancestors are believed to have broken off into two new species.
Which of the following statements is false?
To be enantiomers, a molecule must have at least three different atoms or groups connected to a central carbon.
With radioisotope dating, scientists have estimated that the rocks that contain the fossils of the earliest life forms on Earth, which look like bacteria, are 3.5 billion years old. For what aspect of evolutionary theory does this piece of evidence suggest support?
Today's diversity of life has taken many millions of years to develop.
Why do scientists consider vestigial structures evidence for evolution?
Vestigial structures may or may not be useful, but have anatomical similarities even in very different organisms, suggesting that different populations of organisms evolved from a common point.
Which example most clearly shows a way that humans can respond directly to a change in the environment?
We shiver when we are cold and sweat when we are hot.
A friend says: "Natural selection is about the survival of the very fittest in a population. The fittest are those that are strongest, largest, fastest." Would you agree with that statement? Explain. What evidence from scientific disciplines can you offer to support your agreement or your disagreement?
What is meant by "fittest" is not necessarily strong, large, and fast. Fitness, as defined in evolutionary terms, has to do with survival and the reproduction of genetic material. For example, a small but showy male bird may be selected by female birds to reproduce, while a large but less colorful one is not.
Phylogenetic trees can represent traits that are derived or lost due to evolution. One example is the absence of legs in some marine mammals. One such group is the Cetaceans, which includes toothed whales, such as dolphins and killer whales, and baleen whales, such as humpback whales. Cetaceans are descended from even-toed ungulates and share a common ancestry with the hippopotamus, cows, sheep, camel, and pig. Based on this phylogenetic tree, which of the following animal is the most closely related to a horse?
a cat