GED Practice

GED Science Review: Evolution


Directions: Write your answer on a separate piece of paper.

Question 1 is based on the passage and image below.

A species is a group of organisms whose members can mate with one another and produce fertile offspring. The development of a new species from an old one is called speciation. Speciation may occur when environments change or when groups
separate, moving to different places. The result of speciation is two or more groups of organism than can no longer reproduce with each other.
Sometimes many species rapidly evolve from one species, a process called adaptive radiation. Adaptive radiation can occur after a small group becomes separated from the rest of the population. Sometimes, if the group finds a new home in an area with plenty of space and many diverse resources, it will diverge into several distinct species.

The honeycreeper birds of the Hawaiian Islands are one example of adaptive radiation. The volcanic islands formed millions of years ago in the middle of the Pacific Ocean. Each Island started as a volcano that eventually grew higher than the sea and was colonized by groups became so different that they developed into new species. The diagram shows four beak adaptations found among honeycreepers.
       More than 50 known species of Hawaiian honeycreepers arose to fill available niches and habitats on the new islands. Many of these honeycreepers have specialized diets that are adaptations to life on particular islands. Some of the species feed only on the seeds or nectar of unique Hawaiian plants. Today, only 18 of these remarkable species exist.

  1. A honeycreeper species with a beak similar to the one shown in image 4 on the diagram colonizes a new island with diverse vegetation. Would other honeycreeper species that arrive on the island be expected to evolve a similar beak adaptation or different ones?

    Directions: For question 2, write your answer in the box. For question 3 through 4, write your answers on a separate sheet of paper.

    Question 2 and 3 are based  on the passage and diagram below.

    Cladograms are models that show how organisms are related based on shared, derived characteristics such as hair, feathers, or scales. A derived characteristic is a trait that arose in a particular lineage, or line of descent, at a certain point n time. A derived trait that is shared among different species provides a useful clue to the species' evolutionary history. Specifically, it indicates that those species shared a common ancestor that also had the trait. Scientists may use information in DNA sequence, instead of observable featured to determine evolutionary relationships. Changes in DNA, called mutations, also arise over time. Different changes occur in different lineages.
    The cladogram below shows the relationships among a group of mammals. The short horizontal line at the top left in the diagram represents their common ancestor, a species that lived in the past. where a line splits into two lines, a species gave rise to two different lineages. Each branch in the diagram represents a group of organism that descended from a common ancestor.

  2. approximately how many millions of years ago did the lineages leading to pigs and hippopotamuses arise from a common (shared) ancestor?

    ___________ million years ago
  3. Write a paragraph explaining which two groups of mammals share the most similar DNA. Cite multiple pieces of evidence from the passage and diagram to support your response.

    Question 4 is based on the passage below.

    All populations have genetic variation, meaning that individuals in a population have different alleles, or versions, of genes. Natural selection is the process by which individual that are better able to survive in their environment are also more likely to pass on their genetic characteristics to future generations. Their traits will occur more often in the next generation. In contrast, individuals that are less able to survive and reproduce have traits that tend to be eliminated.
    Antibiotics are drugs that kill specific bacteria. Since the 1940s, antibiotics have been used to control many types of bacterial infections. Populations of bacteria have always contained a few organisms with mutations that make them resistant to antibiotics. Before the use of antibiotics, these organisms were not very common. Now, the widespread use of antibiotics has resulted in some bacterial strains that are resistant to antibiotics. Drug-resistant bacteria pose a health risk to people and animals.
  4. In a paragraph, explain how the development of drug-resistant bacteria strains can be explained by natural selection.

  1. many answers
  2. 60-65
  3. many answers
  4. many answers


Complete Test Preparation for the GED Test 2014 by Steck-Vaughn