What are the smallest objects that biologists study?
molecules
100
What type of electrons is available to form bonds?
Valence
100
What is the process that changes one set of chemicals into another set of chemicals?
chemical reaction.
100
What does the range of a population tell you that density does not?
The areas inhabited by a population
100
Autotrophs capture energy from sunlight or _______ to produce food.
chemicals
200
Biologists who work in the fields of genomics and molecular biology study ______.
DNA
200
What type of ions forms when an atom loses electrons?
positive
200
Enzymes affect the reactions in living cells by changing the
_________.
speed of the reaction
200
Suppose that a species of toads is introduced into a new environment in an attempt to reduce the population of insects. The toad has no natural predators in the new environment. The toad population would most likely ______.
increase exponentially
200
Human activities such as mining and the production and application of fertilizer are part of the ______ cycle.
phosphorus
300
Would a scientist who studies evolution also have to learn about other branches of biology? Why or why not?
Yes; the other branches of biology are interrelated.
300
A solution is a _________.
chemical reaction
300
A mathematical formula designed to predict population fluctuations in a community could be called a(n) _________.
ecological model
300
The various growth phases through which most populations go are represented on ________.
a logistic growth curve.
300
Average year-after-year conditions are to climate as day-to-day atmospheric conditions are to _______.
weather
400
Isotopes are atoms of the same element with the same number of protons and a different number of _______.
neutrons
400
If the pH of stomach acid and of oven cleaner were measured, __________.
the pH of stomach acid would be below 7, but the pH of oven cleaner would be above 7.
400
Phosphorus is very important for living things because living organisms need phosphorus to _________.
form DNA and RNA.
400
In a logistic growth curve, exponential growth is the phase in which the population _______.
grows quickly
400
Because the water is shallow and rich in nutrients, the _______ ocean ecosystem is very productive.
coastal
500
A covalent bond is formed as the result of ________.
sharing electrons
500
Chemical reactions that release energy ________.
often occur spontaneously
500
The photic zone ________.
extends to a depth of about 200 meters.
500
Scientists try to use explanations of the natural world to understand patterns and make _______ about natural events.
predictions
500
Without any limiting factors, a population may grow _____.