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Worksheetsrevision
Total questions: 48
Worksheet time: 32mins
Scientists use observations and data to form and test
constants.
hypotheses.
theories.
conclusions
During an experiment, which factors are observed and measured?
dependent variables
independent variables
constants
hypotheses
The variety of life across the biosphere is called
biodiversity.
genomics.
homeostasis.
ecology
Similar organisms that can reproduce by interbreeding belong to the same
ecosystem.
environment. .
habitat.
species
Which phrase best describes scientific theories?
explain few observations
serve as speculations
are never proven
cannot be replaced
What is the name given for genetic changes in living things over time?
adaptation
homeostasis
evolution
negative feedback
A physical environment with different species that interact with one another and with nonliving things is called a(n)
biosphere.
ecosystem.
habitat.
adaptation.
Organisms rely on both negative feedback processes and behavior to maintain
homeostasis.
adaptations.
ecosystems.
evolution.
particle with a positive electrical charge
(a)
particle with a negative electrical charge
(a)
particle with no electrical charge
(a)
dense center of an atom
(a)
Water (H2O) and carbon dioxide (CO2), are examples of
(a)
are made up of only one type of atom.
(a)
Shared pairs of electrons fill the ______ energy levels of bonded atoms.
innermost
outermost
Covalent bonds are generally
strong
weak.
a bond formed by the electrical force between two ions of opposite charge
(a)
a bond formed when two atoms share a pair of electrons
(a)
the smallest basic unit of matter
(a)
Which property allows water to resist changes in temperature?
high specific heat
cohesion
adhesion
polarity
Which property causes water to form beads?
high specific heat
cohesion
adhesion
polarity
Which property of water helps plants to transport water from their roots to their leaves?
high specific heat
cohesion
adhesion
polarity
Cohesion and adhesion
A solution is a mixture of substances that is _________ distributed throughout the entire mixture.
evenly
unevenly
“Oil and water don’t mix” because ______molecule can’t easily dissolve in a polar solvent.
a polar
nonpolar
A (a) dissolves in a solution.
Carbon atoms form the building blocks of most living things.
true
false
Carbon’s outer energy level is full
true
false
Carbon atoms can form covalent bonds with up to four other atoms.
true
false
Which category of carbon-based molecules includes sugars and starches?
unsaturated fatty acids
phospholipids
proteins
carbohydrates
Fats, oils, and cholesterol are all types of
cell membranes.
hormones.
lipids.
fatty acids.
Proteins are composed of which molecules?
amino acids
b. fatty acids
nucleic acids
monosaccharides
DNA and RNA are two types of
proteins.
nucleic acids.
lipids.
carbohydrates.
Saturated fats are _____in room temperature.
Solid
Liquid
Unsaturated fats are ____in room temperature
solid
liquid
main source for saturated fats are --------source.
animal
plant
main source for unsaturated fats are --------source.
animal
plant
All bonds in saturated fats are single bonds
true
false
All bonds in unsaturated fats are single bonds
true
false
Unsaturated fats have maximum number of hydrogen atoms.
true
false
substances made by a chemical reaction (a)
amount of energy that needs to be absorbed for a chemical reaction to start-----
(a)
amount of energy that will break a bond between two atoms
(a)
state reached when reactants and products are made at the same rate in both directions.
(a)
chemical reaction that absorbs more energy than it releases
(a)
endothermic reaction
exothermic reaction
Which of the following can reduce the amount of energy needed for a chemical reaction to take place?
reactant
product
catalyst
hydrogen bond
bonds between amino acids are called
peptide bonds
energy bonds
aspartic acid, glutamic acid, and serine are examples of amino acids can be distinguished by -------group.
(a)
