Scientific Reading
This is the main idea of a scientific passage—the central point the author wants the reader to understand.
main idea
A pure substance made of only one type of atom.
element
This term describes the maximum number of individuals an ecosystem can support with its available resources.
carrying capacity
A species that is introduced to an area where it is not naturally found and causes harm to the environment, economy, or human health.
invasive species
In scientific reading, facts, data, graphs, or details that support a claim are called this.
evidence
This element has the chemical symbol O and is essential for cellular respiration.
oxygen
Name two limiting factors that affect the carrying capacity of an ecosystem.
What are food, water, space (habitat), shelter, sunlight, disease, predation, or competition?
This invasive species from Asia has spread in the Great Lakes and can disrupt food webs by filtering large amounts of plankton from the water.
zebra mussel
When a graph shows a population increasing for several years and then decreasing, the overall change is called this.
pattern (or trend)
The four elements that make up about 96% of all living organisms are carbon, hydrogen, oxygen, and this element.
nitrogen
A grassland can support 1,000 rabbits, but the population grows to 1,250 rabbits. How many rabbits are above the carrying capacity?
250 rabbits
This is one reason invasive species can spread quickly: they often have few of these organisms in their new environment.
natural predators?
After reading a scientific article, you use facts from the text to explain why an event happened. This science skill is called making a(n):
A. Opinion
B. Inference
C. Guess
D. Prediction only
inference
This chart organizes all known elements by their atomic number and chemical properties.
Periodic Table
A drought reduces the amount of food and water in an ecosystem. What will most likely happen to the carrying capacity?
A. It will increase.
B. It will stay the same.
C. It will decrease.
D. It will disappear completely.
C. It will decrease
An invasive plant grows rapidly and blocks sunlight from reaching native plants. This causes native species to decrease because the invasive plant is __________.
outcompeting native species
"Scientists observed that algae grew rapidly after fertilizer washed into a lake. As algae increased, oxygen levels decreased and many fish died."
Question: What is the best conclusion based on the evidence?
A. Fertilizer improved fish survival.
B. Algae growth reduced oxygen, harming fish.
C. Fish caused the algae to grow.
D. Oxygen increased because of the algae.
Algae growth reduced oxygen, harming fish
An element cannot be broken down into simpler substances by ordinary chemical reactions, but this type of substance is made when two or more different elements are chemically bonded together.
compound
A lake has enough resources to support 500 fish. The fish population reaches 650, and many fish begin to die from lack of food. Which scientific concept best explains this situation?
A. Biodiversity
B. Carrying capacity
C. Photosynthesis
D. Natural selection
B. Carrying capacity
A scientist notices that an invasive species population increases from 50 to 500 individuals in one year. This rapid increase can threaten an ecosystem by reducing __________.
What is biodiversity