Bio exam 4
Consider the following marine community: Sea otters prey on sea urchins and therefore help maintain a healthy sea urchin population. Sea urchins prey on kelp. By helping to maintain viable sea urchin populations, the sea otters are also allowing enough kelp to grow and act as a habitat for other organisms. In this marine community, the sea otter is
A keystone species
A favorable trait that increases chances of survival
Adaptation
Inherited characteristics that increases the chance of survival
Adaptations
Animals and plants have been selectively bred for generations to produce certain desired phenotypes. This is an example of
Artificial selection
Human breeders, rather than the environment, select the variations of traits to be passed to offspring
Artificial selection
___ and ___ grass that gains energy from the sun
Autotroph and producer
Closely related species often have similar stages in their embryonic development
Comparative embryology
Darwin cites evidence for the theory of evolution. One type of evidence is represented by this diagram. During embryonic development, a chicken and a human both have pharyngeal gill slits. This is an example of
Comparative embryology
Two species of sea anemones trying to vie for the same limited resource
Competition
Fungus and bacteria make nutrients available for producers to reuse
Decomposers
Competition for limited food and nesting sites
Density dependent
Effect depends on the density of a population
Density dependent
Non native snakes released into a wetland to prey on native rodents
Density dependent
An unexpected freeze that kills a population of squirrels
Density independent
Effect does not depend on the density of a population
Density independent
Flood waters cover a field of wildflowers
Density independent
Habitat destruction due to an oil spill
Density independent
Wildfires spread through a grassland
Density independent
Larger squirrels can carry larger acorns to their burrows, and they outcompete small and medium squirrels when acorns are limited. This is an example of
Directional selection
The occurrence of large and small beak sizes among seed cracker in the absence of medium sized beaks is an example of
Disruptive selection
Organisms within a population have differences in traits
Variation
In humans, the pelvis and femur are involved in walking. In whales the pelvis and femur shown are...
Vestigial structures
Remnants of features that served important functions in an organism's ancestors but are reduced and nonfunctional in other similar groups
Vestigial structures
Species make up populations, which make up
communities
A prairie dog, a hawk, and a badger all are members of the same
community
Fish, frogs, turtles, lily pads and dragonflies are all members of the same what?
community
Long necks make it easier for giraffes to reach leaves high on trees, while also making them better fighters in "neck wrestling" contests. In both cases, which kind of selection appears to have made giraffes the long-necked creatures they are today?
directional selection
An Acacia tree provides food and shelter to ants, which then keep herbivores away from the tree. Which is best represented by this relationship?
mutualism
The chance of an individual migrating to another population and sharing its genes there
Gene flow
The four mechanisms of evolution are
Gene flow Genetic drift Mutations Natural selection
All the ants in an anthill
population
All the blackbirds in your neighborhood
population
The change in allele frequencies in a population due to chance events, such as from the founder effect and bottleneck event
Genetic drift
In order for a population to evolve, organisms in the population must have differences known as
Genetic variation
All species share a common genetic code, suggesting that all forms of life are related through branching of evolution from a common ancestor
Molecular biology
Changes in DNA sequence, usually occurring because of errors in replication or repair
Mutations
The ultimate source of genetic variation
Mutations
Lichen is composed of a fungus that protects the algae while the algae provide food produced during photosynthesis
Mutualism
The Nile crocodile open its mouth to permit the Egyptian plover to feed on any leeches attached to its gums. The small bird gets to eat and the croc gets its teeth cleaned
Mutualism
The process in which organisms with adaptations more suited to the current environment are more likely to survive and reproduce than are individuals without them
Natural selection
Animals that eat a variety of meats, fruits, and vegetables
Omnivores
If a bear eats a fish that ate bugs that ate algae, the bear is a
Tertiary consumer
Small lizards have difficulty defending their territory, but large lizards are more likely to be preyed upon by owls. Which type of selection would act on body size in these lizards under these conditions?
stabilizing selection
Starlings produce an average of five eggs in each clutch. If there are more than five, the parents cannot adequately feed the young. If there are fewer than five, predators may destroy the entire clutch. This is an example of
stabilizing selection
Succession on abandoned New England farm
Secondary
If a lion eats a zebra that ate grass the lion is a
Secondary consumer
All the living and non-living things in an area
Ecosystem
Aquarium with fish, plants, snails, and rocks, water, and food
Ecosystem
a community of organisms and their abiotic environment
Ecosystem
"Descent with modification", the idea that species share a common ancestor, change over time, and give rise to new species
Evolution
Suppose that a bacterial infection swept across a sea otter population and killed most sea otters before they could reproduce. How would the marine community be affected?
For a period of time, there would be no overpopulations of sea urchins and therfore a decline in kelp populations
If whales evolved from four-legged land animals, then transitional forms should have reduced hind limbs and pelvic bones
Fossil evidence
The different versions (alleles) of a trait must be able to be passed (in sperm or egg) from parents to offspring
Heritability
An organism that gets energy by eating other organisms
Heterotroph
Forelimbs of all mammals are constructed from the same bone structures, but have evolved different functions
Homologous structures
More organisms will be produced than will survive
Overproduction
Tapeworm living inside the intestines of an animal host
Parasitism
Young wasps are eating the tomato hornworm that is their host
Parasitism
A lynx is attacking a hare
Predation
An undersea volcano erupted and formed a small island. Mosses and lichens began to grow on the bare volcanic rock
Primary
Begins in a virtually lifeless area where soil has not yet formed
Primary
Usually begins with the establishment of lichens
Primary
If a person eats a vegetable, the person is acting as a
Primary consumer
Charles Darwin realized that the measure of success for an organism was not only a long period of survival but also successful.....
Reproduction
Individuals with the version of a trait most suited to reproduction in their environment genre leave more offspring than individuals with other versions of the trait
Reproductive success
An old house was torn down. Small weeds and grasses grew in the vacant lot. Over the next few years, bushes and tree seedlings began to grow
Secondary
Starts with previously existing soil
Secondary
Succession as a result of a forest fire or flood
Secondary