JLab answers
Based on the position of the wings, which of the insects below is most likely in the order Hemiptera?
(they are images but it is the one that resembles a beetle)
Fifty banded and fifty unbanded snails of the same species were released in an area where the banded snails are easily camouflaged. Which of the following best represents the population of these snails after one year?
(they are images but it's the one with the high amount of Banded snails and low amount of Unbanded snails)
An experiment determined that 20 g of mass were gained by a mouse on a corn diet, 15 g by a mouse on a rice diet, and 18 g for the mouse on a grain diet. The corn-fed mouse started out at 95 g, the rice-fed at 98 g, and the grain-fed at 92 g. Which of the following tables describes these data and any other data which can be directly computed from these numbers?
(they are images but the table reading "Corn-fed, 95, 115, 20, 21%" on the first row)
Which of these would be the best way to prove that a pine stick is more flexible than an oak stick?
(they are images, the image with a 300 gram weight tied to both the oak and pine stick)
The picture above shows a flask of hot water. This test was carried out to find out which type of container would hold heat the longest. Which of these graphs bests shows all of the data from this experiment?
(they are images, the line graph that stops at 6 minutes)
Which of these represents the freezing point of water in correct SI units?
0°C
Which of these best completes the Conversion Table?
1 km = 1,000 m // 1 m = 100 cm
In the scale model above, one centimeter is equal to one-half of a meter. The mailbox is two truck lengths away from the model truck. How far away is the mailbox from the truck on the real street?
10 Meters
The picture shows the growth curve of a bacterial population. According to this information, the bacterial population doubles every -
20 Minutes
What is the mass of the rock?
354.6 g
At which of these points is it 12:00 noon?
4
A scale model of the planet Mercury is shown. Based on the scale, which of the following is the most accurate diameter of Mercury?
5,000 km
This chart represents the type and number of items collected in a beach cleanup. Based on the above chart, what percentage of the total items collected from the beaches was plastic?
56%
Artificial lights can create a great deal of heat. If a gardener wanted to grow seedlings indoors that grow best at 25°C, which light intensity should be used?
60 candelas
Which of the following is an example of a decomposer at work in the food web?
A fungus growing on a log
Which biome contains large populations of grazing herbivores, few species of birds, and deep, rich soil?
A grassland
Which body in the solar system usually contains an atmosphere?
A planet
The loss of which of these would have the least effect on the water cycle?
Animals
Ranchers historically have used genetics to produce new varieties of cattle. Buffalo can tolerate both hot and cold temperatures but have meat that is not as tasty and tender as beef. Cattle that are subjected to severe temperature extremes produce meat that is neither tender nor good-tasting. What good qualities might a "beefalo" (cross between cattle and buffalo) possess?
Animals that tolerate heat and cold and have good-tasting meat
Which is an abiotic change in an ecosystem?
Annual rainfall totals for an area increase.
Which of the following is used to measure the mass of an object?
Balance
Fossils are evidence of living things that were alive many, many years ago and often consist of the skeletons of creatures imbedded in rock. Why don't fossils contain the animal's soft tissues, as well?
Because the soft tissues decayed before the fossil could be formed
A group of people were concerned about a new coal-burning power plant that might be built in their neighborhood. What is probably their main concern?
Burning coal produces sulfur dioxide which contributes to acid rain.
Plants release oxygen into the air as a result of photosynthesis. Which of these do plants need for photosynthesis?
Carbon dioxide
Which of these is a way that a person can help improve air quality?
Carpool with several people
Which animal has a life span closest to that of sheep?
Cat
Which of these shows the correct sequence of development?
Cells → tissues → organs → systems
A plant's green color is due to the presence of which organelle?
Chloroplast
Which of these are found in plant cells but not in animal cells?
Chloroplasts
During human fertilization, an egg and a sperm cell unite. Which structures in these cells carry the genes that will be transferred to the offspring?
Chromosomes
The Earth makes a complete rotation once every 24 hours. Which of these would best illustrate rotation?
Coin Spinning
Asexual reproduction involves only one parent. The offspring of this type of reproduction have -
DNA identical to the DNA of the parent
Which is an SI metric unit of measurement that is used to record the heat transfer of a solution in a classroom investigation?
Degree Celsius
How should the fruit above be classified?
Drupe
Which of these is due entirely to inheritance in humans?
Eye color
Which characteristic is common to the four outer planets in our solar system?
Gaseous composition
The line graph shows five years of data about a dog. What information does the graph show?
How the mass of the dog changed
Which of these best shows what is happening to the cell in pure water?
Image labeled "Water going to cell"
According to the graph, which air pollutant decreased the most from 1970 to 1991?
Lead
Each student in a science class of 25 conducts the same experiment. One student gathers all the data from her classmates and summarizes the results of the experiment for the class. She compares the data she personally recorded with the class data. Which of these might indicate to her that her results are valid?
Many other students recorded data similar to hers.
Scientists have been able to find no atmosphere around this planet because it has little gravity and is closest to the sun. The planet described is -
Mercury
Where is water most likely to become contaminated?
Near a cattle farm
In 1500, between 60 million and 125 million American bison roamed the plains. These bison were used by Native Americans as a primary food source, but this did not have much effect on the bison population. A few hundred years later, railroad crews and settlers moving west also depended on the bison for food. By 1892, it is estimated that less than 1,000 bison were left. What were the two main causes of the near-extinction of the bison?
Overhunting and loss of habitat
Which of these species would be most in danger of becoming extinct if one of their food sources became unavailable?
Panda
What process makes food for plants?
Photosynthesis
Which process is the foundation for the food web?
Photosynthesis
Which of these populations is most likely to increase if the number of grasshoppers decreases?
Plant
Which of these objects in the solar system was the most recently discovered?
Pluto
The diagram shows a graduated cylinder containing water. From which position will the most accurate measure of the volume of the water be made?
Position 3
Of the following, which is the correct progression in the food chain?
Producers → herbivores → carnivores
In which biome would you find the most variety of life?
Rain forest
Black bears roam over large territories. What effect would building shopping centers in these territories have on the bears?
Reduce the black bears' habitat
A student measured the power of a motor operating at different temperatures. The student recorded a total of 11 measurements, one at each 2 degree interval between 10°C and 30°C. Which change in the procedure would most improve the validity of conclusions based on this investigation?
Repeating the experiment several times
Which of the following classification groups contains organisms that have the most characteristics in common?
Species
Which of these has the strongest gravitational field?
Sun
Cells → Tissues → Organs → ?
Systems
The picture shows a pond ecosystem. What would most likely happen if all the lily plants were removed from this community?
The animals would have fewer places to hide.
Using the above table, what can you say about the relationship between each food and the mass of the mouse?
The mixture-fed mouse gained the most mass.
Which of these is most likely the result of weasels and foxes depending on the same food source?
The populations will compete with each other.
Which of the following causes the Sun to appear to set?
The rotation of the Earth
Some snapdragon seeds were studied in the experiment above. The seeds were placed in a dish lined with a moist paper towel. Which of these is the independent (manipulated) variable in this experiment?
The temperature of each dish
Crickets chirp to attract other crickets. The temperatures and rates of their chirping are graphed above. Which statement below is most likely true for the data represented in the graph?
The warmer the temperature, the more often crickets chirp.
After fishing in the ocean, a student left his fishing gear in the sun to dry. Later, he noticed that small white crystals had formed on the rod, reel, and fishing line. Which of these is the best explanation of what occurred?
The water evaporated from the fishing gear, and salt from the ocean was left behind.
The graph shows the relationship between the time of day and the amount of carbon dioxide in a certain pond. Which of these best describes the relationship?
There is more carbon dioxide used up by algae later in the day.
What most likely happened to species that are found in the fossil record but have no living members?
They became extinct.
What is the role of the Orca in this food chain?
Third-order consumer
Which type of characteristics can be inherited?
Those controlled by genes
A student wishes to measure the mass of an object. Which instrument would be most useful?
Triple beam balance
The picture shows a test for non-slip surfaces to be used on a ramp. Which of these must be done to provide more meaningful results?
Use the same shoe on each surface
In this diagram of a single-celled organism, which organelle functions as a place to store extra water?
Vacuole
A coal-burning facility is constructed in an area containing several pond ecosystems. How will this human activity most likely affect the pond ecosystems?
Water quality will be reduced.
Students measured the amount of an unknown substance that dissolved in water at different temperatures. What was the independent variable in this investigation?
Water temperature
Which of these would be different for an object if measured on the Earth and on the moon?
Weight
Many complex genetic experiments have been performed on plants. One of the very successful ones crossed wild wheat with a fungus-resistant wild grass. This ultimately produced a variety of wheat that was resistant to a very destructive parasitic fungus which kills nonresistant plants. Why would such experimentation benefit humans?
Wheat is one of the most important food crops worldwide.
Which one of the above objects is heaviest?
White long oval
A cold air mass moves underneath a warm air mass causing the warm air to rise. This event can best be identified as -
a cold front
It is important to protect air quality because -
acid rain is caused by air pollution
The diagram shows a simple food web of organisms on a forest floor. Which of these is most dependent on the earthworm for its food supply?
centipede
Hurricanes form in tropical waters between 8 and 20 degrees north and south of the equator. Hurricanes rarely form at higher latitudes because the water is too -
cold
This experiment was set up to test the hypothesis that plants grow faster in green light. What is the independent variable in this experiment?
color of light
Lions usually live in prides made up of a few adult females, an adult male, and some younger lions. The females hunt together and the kill is shared with the pride. The lions' method of hunting best illustrates -
cooperation
The function of a cell nucleus is to -
direct the activities of the cell
White-footed mice having thicker fur than cactus mice is probably influenced most by the differences in the -
environmental climates where they live
According to this diagram, both of these fish -
get their energy from other animals
The force that holds objects close to Earth is called
gravity
The force that holds the planets in orbit around the sun is called -
gravity
Earth is different from the other planets in our solar system because it -
has oceans and lakes
During mitosis, the doubling of chromosomes ensures that both new cells -
have identical genetic makeup
The ermine is a small animal that lives along riverbanks and in forests. During the spring and summer, it grows a brown coat. It sheds the brown coat during the autumn and grows a white one. This change of color in the ermine's coat allows it to -
hide from predators
Which of these best completes the statement about the interaction of the respiratory system with the circulatory system? The lungs add -
oxygen to the blood
A tapeworm lives in human intestines, absorbing the nutrients that would normally be absorbed by the person. This eventually causes the person health problems. The relationship between the tapeworm and the human is -
parasite/host
Energy from the Sun is distributed around Earth by -
radiation and convection
Northern garter snakes exhibit a unique behavior in which they gather in deep dens by the hundreds or thousands. They then coil together in a huge ball. This behavior could help to -
reduce heat loss
The quality of air is monitored by the government to determine whether a city needs to take steps to control air pollution. To best measure air quality, the air should be tested -
several times a day in all kinds of weather
The best scientific reason for a scientist to accept a specific theory is -
that research and observations support the theory
The diagram above shows the changes over time in the horse. Evidence for these changes most likely came from -
the fossil record
A farmer wants to plant a crop that grows well in a marshland environment. In order to produce a good harvest, the most important characteristic this plant should have is the ability to -
thrive in wet soil
One way plants and animals are alike is that they both -
use oxygen
In this plant cell, which cellular structure is responsible for storing food, water, and wastes?
vacuole
John and Emily were experimenting with the effects of road salt on plant growth. To do this, they watered plants daily with the same amount of salt water. They could best improve their experiment by -
watering half the plants with pure water and half with salt water
One complete revolution of a planet around the sun equals one
year