Life Science

Which statement describes the organization of living organisms?

All organisms are composed of one or more cells, which are the basic units of structure and perform essential life functions.

An immune response to a usually harmless environmental substance is know as

An allergy

Polarized sunglasses are used to cut glare from sunlight reflected at a glancing angle off cars, water, and other surfaces. Such sunglasses are a practical application of which of the following physical principles?

Brewster's law

An immune response is primarily due to the body's white blood cells recognizing

Foreign antigens

Sperm and egg cells are referred to

Gametes

Human egg cells are produced in the

Ovaries

What is one way the respiratory system and the circulatory system work together in the human body?

The respiratory system takes in oxygen, and the circulatory system delivers the oxygen tot he cells of the body.

Plants are classified according to their structures. The plant picture below reproduces without seeds and has simple tubes for transporting water.

spore-producing plants with many leaves

Conclusions based on an experiment are most likely to be accepted when

they are consistent with experimental data and observations

A diploid human cell contains

46 pairs of chromosomes

The Burgess Shale is a rock formation in Canada that has a large number of fossils from the Cambrian period preserved in exquisite detail. Many primitive members of modern phyla, including arthropods, mollusks, and chordates, can be found among the fossils, it can be concluded that most of the modern groups of animal life first appeared roughly?

540 million years ago

Students in Ms. Alvarez class are investigating how temperature, in degrees Celsius, affects the solubility of a compound in 100 milliliters of water. Ms. Alvarez provides the students with a graph that shows the solubility of a certain compound, as shown below. She tells the students that she will demonstrate how many grams of the compound will dissolve in 100 ml of water at 40 degrees C. Based on the information in the graph, which of the following is the best prediction of how many grams of the compound will dissolve at 40 degrees C?

65 grams

A student designed an experiment to determine if air temperature had an effect on the rate of photosynthesis in corn plants. Which tool is correctly paired with a procedure that could be used during this experiment?

A graduated cylinder to measure 30ml of water for each plant daily

The diagram below shows a person using a simple machine to lift a box. The box is being lifted with the help of

A pulley

The fight-or-flight response includes greater heart output and a rise in blood pressure. This response is due to

Adrenaline secreted by the adrenal glands

A student designed an experiment to determine if air temperature had an effect on the rate of photosynthesis in corn plants. The independent variable in this experiment is the

Air temperature at which the corn plants were grown

The offspring of many species amoeba are genetically identical to their parent, while the offspring of most mammal species are genetically different from their parents. Which most likely explains the genetic differences in the offspring of amoebas and mammals?

Amoebas reproduce asexually, but mammals reproduce sexually

Why is photosynthesis important to the survival of green plants?

Because it provides energy and food necessary for growth

A plant is placed in front of a window inside a classroom. Over time, its stem and leaves bend toward the light. Why does this occur?

Because the sun is a positive stimulus

Ethan is observing chemical and physical properties of a substance. He heats a substance and observes that the substance turns from a brown solid to a black powder. He refers to several chemistry journals that claim this represents a chemical reaction. From his observation and research, he concludes that the substance goes through a chemical change when heated. How can Ethan best defend his conclusion?

By verifying that the substance is now made up of different molecules than before it was heated

Single-celled organisms are able to maintain homeostasis, even though they lack higher levels of organization such as organs and organ systems because

Cell structures work together to maintain homeostasis in single-celled organisms

Which two factors could lead to the evolution of a species over time?

Changes in the genes of sex cells and survival of the fittest

Which system in a multicellular organism functions most like the cytoplasm in a single-celled organism?

Circulatory

What is the best way to determine if a sample is pure gold?

Compare the melting point of the sample with a sample of pure gold

Stability within an ecosystem is achieved partially by the presence of organisms that break down important molecules and make them available for other organisms to use. These organisms are

Decomposers

The geologic map above, from an area with low topographic relief, shows four rock units labeled A-D, from the oldest to the youngest. What structure is represented on the map?

Dome

The organic compounds that scientists use to cut and move segments of DNA are

Enzymes

In an effort to reduce the number of deaths due to malaria, scientist have successfully introduced a gene into mosquitoes. The gene makes mosquitoes unable to support the development of the parasite that causes malaria. The technique used to produce this new variety of mosquito is most likely.

Genetic engineering

Lobsters are crustaceans related to crayfish, crabs, and shrimp. Most lobsters are a reddish-brown color, but on rare occasions, they can be orange, blue, or even multicolored. These color differences can be caused by

Genetic variations

An astronaut drops a hammer on the Moon, and a scientist drops an identical hammer on Earth. Both hammers are dropped from the same height. The hammer dropped on Earth falls to the ground faster that the hammer dropped on the Moon. Why does the hammer on Earth fall faster than the hammer on the Moon?

Gravitational attraction is stronger on Earth than on the Moon because Earth has a larger mass.

Which of the following energy sources does NOT originally come from the Sun?

Hydroelectric

An example of a naturally occurring diatomic molecule is

Hydrogen gas

Which function does the nucleus of a cell perform?

It controls the activity of the cell

A large tree in the forest blocks the sunlight for a smaller plant. How could this affect the smaller plants?

It could decrease the amount of food produced by the smaller plant

How is a gamete different from other types of cells in a person's body?

It has half the number of chromosomes

Which best explains why muscle is considered a tissue?

It is a group of cells working together

An invasive species, the spiny water flea, was recently found in a lake. These water fleas eat zooplankton, a food also consumed by native fishes. The fleas spread from lake to lake by attaching to fishing lines, anchor ropes, and boats. Which statement best describes the effect of the water flea on the lake?

It will feed on organisms that are important to other species.

Which of the following activities is likely to have the greatest impact on biodiversity?

Large-scale deforestation of the Amazon or Congo basin tropical forests

A metal that can be hammered into thin sheets demonstrates the property called

Malleability

Genetic researchers have discovered a number of different gene mutations that have led to the development of cancer. These mutations affect how frequently a cell reproduces. Which process would be directly influenced by these mutations?

Mitotic cell division

Many organisms live in the forest. The taller trees in the forest are often cut down for wood. How can this change the environment be helpful to plants?

More sunlight reaches the ground resulting in new growth

A stable ecosystem can have high biodiversity because each species in that ecosystem

Occupies a different niche

How do some plants defend themselves against predators?

Plants can have thorns on their stems and or poison on their leaves

A communication satellite is in a circular orbit around Earth. If the speed of the satellite is constant, the force acting on the satellite

Points toward the center of Earth at all times.

Striking the tendon just below the kneecap causes the lower leg to jerk. Moving an object quickly toward the face can cause the eyes to blink shut. They are examples of

Reflex reactions

While looking at the bottom surface of a leaf with a compound light microscope, a student notices pairs of cells with openings between them on the surface of the leaf. The main purpose of these openings and the cells that surround them is

Regulating gas exchange

Sharks are often followed by smaller fish that can eat some of the scraps from the organisms eaten by the shark. These smaller fish are acting as?

Scavengers

The graph below compares the density, in grams per cubic centimeter (g/cm3), of four different substances. Based on information from the graph, which of the following best compares the physical properties of two of the substances?

Substance Y would have less mass than substance Z would have if they had the same volume

Fusion is a form of nuclear reaction resulting in an enormous release of heat energy. The fusion of hydrogen to helium is a reaction that commonly occurs in

The Sun and typical stars.

The highest concentration of ocean life is found in the top 200 meters of the ocean. What is the most important factor in the ability of plants to grow in the ocean?

The amount of sunlight received

Millions of years ago, a small population of birds lived on the Hawaiian Islands. Over time, this population evolved into more than 54 separate species, each with different color, beak shapes, and food sources. Which of the following best explains why the original population of birds evolved into so many different species?

The bird population moved into and adapted to many different environments on the Hawaiian Islands.

How do the digestive system and the circulatory system work together in the human body?

The digestive system extracts nutrients from food, while the circulatory system transports those nutrients.

What would occur if the anthers were removed from a flower?

The flower would be unable to produce pollen

Which of the following statements is correct about a trophic structure in which a leaf-eating grasshopper is eaten by a frog, which in turn is eaten by a snake?

The grasshopper is the primary consumer

The true length of a block of wood is 1.010 cm. Three measurements of this block produced the following values: 1.4 cm, 1.2 cm, and 0.9 cm. Which of the following statements is true concerning these measurements?

They are neither precise nor accurate

How do decomposers contribute as a part of a food web?

They break down organic matter and produce different forms of energy.

A scientist performs an experiment and asks other scientists around the world to replicate it. Why would other scientists most likely try to perform the same experiment?

To confirm the results of the experiment conducted by scientist

Food webs show feeding relationships among different types of organisms. Those organisms each have a specific niche. Which of the following best describes a function of decomposers in food webs?

To recycle nutrients into soil

To clone a mammal, a cloned embryo is often put into an adult female of the same species to continue internal development. The structure in which the embryo will develop is the

Uterus

Strawberry plants can reproduce both sexually and asexually. Strawberry farmers use both kinds of reproduction, depending on the desired outcome. In which of the following situations would a farmer most likely want the strawberry plants to reproduce sexually?

When developing new varieties of fruit

A skunk's odor is unpleasant to other animals. A monarch butterfly's coloration warns birds of its bitter taste. These adaptations help these animals to

avoid predators

The diagram below represents a plant cell. Which process takes place in structure A?

cellular respiration

Frogs eat crickets. If the population of crickets in an area decreases, the number of frogs in the area will most likely

decrease

A prairie dog whistles loudly when it senses danger. When it whistles, all of the prairie dogs nearby run and hide in their burrows. Which sense helps the other prairie dogs receive this warning?

hearing

The existence of which group of organisms spans the shortest geologic time?

humans

Most of the long-wave energy radiated from Earth and lost to space on a cloudless night is

infrared

When the food supply in an area decreases, many of the deer living there will

move to a new habitat

The diagram below shows an eagle that has captured a rabbit for food. The rabbit is an example of a

prey

The main purpose of a plant's flower is to

produce seeds

As human red blood cells mature, they lose their nuclei. As a result of this loss, which process would be impossible for mature red blood cells to carry out?

reproduction

Which life process is common to all living things?

reproduction

Which human activity would most likely deplete finite resources?

uncontrolled population growth

The diagram below shows a spring scale. The spring scale is being used to measure the rock's

weight