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