Why do viruses need living hosts, such as bacteria or eukaryote cells?

A forest ecosystem can support a limited number of bears. This is because

An animal lives in an area with cool temperatures. Climate change has caused the temperature to grow warmer. Which of these adaptations would BEST help the animal adapt to the changes in temperature?

Dead zones in the ocean are places where organic material is decomposing, using up all the oxygen. Which of these activities will be most affected by one of these zones?

High biodiversity helps an ecosystem be more sustainable because:

Coyotes & hawks prey on rabbits that eat grasses in the Texas grassland. If we had 4 years of drought, what would probably happen to the population of these animals?

The Gulf of Mexico is full of sediment because of all the rivers that drain into it and make it so nutrient rich. If half of those rivers were dammed up, what would happen to the biodiversity of the area?

In the rainforest, trees grow narrow and tall and very quickly. Why is this?

Arctic foxes are white in the winter and brown in the summer to be better camouflaged. If the arctic continues to warm up, and their is eventually less snow, what might happen to the foxes to help them survive?

A bee flies from flower to flower collecting nectar. He also gets pollen from one flower on himself and deposits it onto another flower when he lands on it, pollinating it. This is an example of:

Ticks get onto dogs and drink their blood which can transmit diseases to dogs and eventually make them sick. This is an example of:

Cattle egrets eat the insects stirred up by cattle when they are grazing. The cattle are unaffected, while the birds gain food. This is an example of:

_________________ is any type of a close and long-term biological interaction between two different biological organisms.

Which of the following is NOT an example of how biotic factors interact

with abiotic factors in an ecosystem?

Plants need sunlight to perform photosynthesis. In the tropical rainforest, the survival of a plant depends upon its ability to adapt in order to reach sunlight.

Which of the following is an example of one such adaptation?

A company purchased a large forest and cut the trees for

lumber. Sunlight which had not reached the forest floor before was now very bright on the bare ground. Holly ferns began to grow rapidly because of increased access to light and moisture.

Which population of organisms would be in direct competition with the Holly ferns for the same resources?

The Texas blind salamander lives exclusively in San Marcos, Texas and has the following characteristics.

Characteristics of the Texas Blind Salamander

--Blood rich gills that allow them to breathe in their aquatic environment

--There are no eyes present Very little skin pigment to protect them from ultraviolet radiation

--Able to sense pressure changes in the aquatic environment to detect prey

--Adults eat snails and blind shrimp

Which abiotic resource is not likely present in the Texas blind salamander’s environment?

In Austin, Texas, a well-known salamander inhabits the waters of the spring outflows of Barton Springs. This is the perfect habitat for the Barton Springs salamander since it thrives in fresh and pure continuous flowing water. They may inhabit underground or surface environments. They have been observed in water, under and among rocks and gravel, as well as within plants and algae. They consume small aquatic organisms.

What is the most likely way that humans could have a damaging impact on the Barton Springs salamander?

A particular type of bird carries the genes for its offspring to either have a short, strong beak or a long beak. The strong beak is great for crushing nuts, while the longer beak is used to get to water in little spaces. Normally, 75% of the bird population have short, strong beaks while only 25% have long beaks.

If the area in which the birds live experiences a 50-year drought, what change in beak type could be expected in the population?

Threespine Stickleback fish eggs hatch in the streams formed from mountain snowmelt. The streams carry the adult Threespine Stickleback fish to the ocean where they live until they swim upstream to lay eggs to begin the next life cycle. In 1964, an earthquake in Alaska turned some of the streams into ponds that were completely cut off from the ocean. Today, Threespine Stickleback fish can still be found in the ponds formed by the earthquake.

How did the traits of Threespine Stickleback fish have to change to be able to survive in the ponds?

Phytoplankton are microscopic organisms that perform photosynthesis in oceans. When urban pollution runoff makes it to the oceans, it poses a threat to humans by killing numerous phytoplankton.

How does reducing the number of phytoplankton most directly affect humans?

Coral reefs support more species than any other marine

environment. The biodiversity in a coral reef is great, and scientists estimate that there may be another 1 to 8 million undiscovered species of organisms living in and around reefs. Reef structures protect shorelines against waves preventing the destruction of beaches and coastal property.

An artificial reef is a man-made structure that mimics some of the characteristics of a natural reef. Often, old ships and even subway cars are sunk off the coastal shore to create an artificial reef environment.

What is the greatest benefit an artificial reef would provide to the people living along the coast?

Which is the most likely outcome to the organisms in an ecosystem near the site of a nuclear disaster?

In the summer in Salt Lake City the smog seems to hang in the valley for days or weeks.

As species go extinct what will happen to the biodiversity in that ecosystem?