Science part 1a

Which statement describes a failure of homeostasis in humans?

A viral infection leads to a decrease in the number of white blood cells being produced in the body.

Gene editing can be used to swap out an unwanted gene for a desirable one from the same species. Which statement best explains why the desired gene will be found in all cells that come from the genetically edited cell?

The altered DNA in the edited cell will be replicated and passed onto each new cell during mitosis

As blood glucose levels increase, hormones are released to return glucose levels to normal. This is an example of

a stimulus and a response

In humans, embryonic development during the first two months is more sensitive to environmental factors than during the remaining months. The best explanation for this statement is that

during the first 2 months, organs are being formed and any unusual change during cell division can interfere with normal development

Which human activity has the potential to greatly affect the equilibrium of an ecosystem?

emptying an aquarium containing nonnative fish of several species into a local lake

Genetically identical yarrow plants were grown at different altitudes. Even though their genetic makeup was identical, the plants grew to different heights. One likely explanation for the different heights of the plants at each altitude is that (1) gene expression was influenced by the environment

gene expression was influenced by the environment

Which sequence of events best represents ecological succession?

grass grows on a sand dune and is slowly replaced by shrubs

BRCA genes are human genes that normally work to help shut down cancer cells before they can harm the body. Scientists have learned that individuals inheriting a damaged form of a BRCA gene are at greater risk of developing breast or ovarian cancer. This discovery is an important first step in

identifying individuals at risks and recommending preventive treatment.

Sustainable development occurs when people use their resources without depleting them. Which human activity is the best example of sustainable development?

loggers planting a tree for each one cut down.

Some environmental engineering companies have recently designed manufactured wetlands to serve as natural sewage treatment plants. Utilizing the ability of wetland organisms to reduce human wastes makes use of naturally

nutrient cycles

Ringworm is a skin infection common among school-aged children. Although the name suggests that a worm causes the disease, it is actually caused by a fungus that lives and feeds on the dead outer layer of the skin. The relationship between ringworm and humans can

parasite\host

A hummingbird may need to consume up to 50% of its body weight in sugar each day, just to meet its energy needs. Some of this energy is stored and some is used for metabolic activities, but much of the energy is

released as heat energy back into the hummingbirds environment.