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What is 1 + 3?
Which of the following statements about the properties of life is false?
All organisms have the ability to maintain a constant internal temperature.
Life is organized in a hierarchy fashion. Which of the following sequences correctly lists that hierarchy as it increases in complexity?
Molecule, cell tissue, organ, organ system, organism, population, community, ecosystem.
The tree in your backyard is home to two cardinals, a colony of ants, a wasps nest, two squirrels, and millions of bacteria. Together all of these organisms represent
If you eat a hamburger, you are mainly eating ground-up beef muscle. What levels of organization are represented in this ground-up muscle?
Organelle, cell, and tissue
Which of the following statements about ecosystems is false?
Bacteria and fungi recycle energy within an ecosystem
The ultimate source of energy folowing into nearly all ecosystems is
A consumer eating a producer represents
a transfer of chemical nutrients and energy
Which of the following statements regarding a common cellular activity is false?
New cells are derived from cellular components like organelles
Which of the following statements about living systems is false?
Living systems are composed of two or more cells
Organisms that are prokaryotes are in the domains
Fungi and bacteria
Which of the following statements about the domain bacteria is true?
All bacteria lack a nucleus
Members of the kingdom animalia
can obtain their food by eating other organisms
What feature is common to prokaryotes, fungi, and plants?
Which of the following is a kingdom within the domain Eukarya
All organisms belonging to the kingdom Plantae
are photosynthetic and contain cells that are surrounded by cell walls with cellulose
All organisms belonging to the kingdom fungi
include mushrooms and yeasts, and decompose the remains of dead organisms and absorb nutrients from the leftovers
....These cells must come from an organism that is a member of the kingdom
Which of the following observations would provide the strongest evidence that the many different plants that we call orchids are actually related to one another?
they all have the same common ancestor
The teeth of the grain-eating...This illustrates
a result of natural selection and the connection between form and function
An antibiotic kills 99% of a bacterial population. You would expect the next generation of bacteria
to be more resistant to that antibiotic
Consider the following statement....This statement is an example of
A hypothesis is
a tenative answer to some question
A theory is
an explanation of an idea that is broad in scope with multiple lines of evidence
To be scientifically valid, a hypothesis must be
testable and falsifiable
The role of a control in an experiment is to
provide a basis of comparison to the experimental group
A scientist performs a controlled experiment. This means that
two experiments are conducted, one differing from the other by only a single variable
Which of the folowing best represents an example of technology
testing for genetic diseases
As the enviroment changes,
natural selection adapts populations to their enviroment
Which level in the hierarchy shown is a community?
Which of the following organisms belongs to the group represented in Box 1
The four most common elements in living organisms are
C, H, O, N, P, S
Which of the following statements regarding matter is false
Matter can be created and destroyed
Which of the following statements best describes a compound
a coumpound contains two or more different elements in a fixed ratio
In the equation 2 H2 + 2 H20,
only H20 is a compound
Which of the following particles is found in the nucleous of an atom
protons and neutrons
What is the atomic mass of an atom that has 6 protons, 6 neutrons, and 6 electrons
An uncharged atom of boron has an atomic number of 5 and an atomic mass of 11. How many electrons does boron have?
The sodium atom contains 11 electrons, 11 protons, and 12 neutrons. what is the mass number of sodium
Which of the following best describes the atomic number of an atom
the number of protons in an atom
Typically nitrogen atoms are composed of electrons, protons, and neutrons.An isotope of nitrogen could
have more neutrons
A radioactive isotope is an isotope that
When full, the innermost electron shell of argon contains __ electrons, and hte outermost shell contains __ electrons
Table salt is formed when
sodium donates its single outer electron to chlorine
A(n) ____ forms when two atoms share electrons
A hydrogen atom has one electron. How many covalent bonds can hydrogen form?
What is the fundamental difference between covalent and ionic bonding?
In a covalent bond, the partners share a pair of electrons; in an ionic bond, one partner accepts electrons from the other
Which of the following statements regarding the oxygen atom of a water molecule is true?
oxygen is more electronegative than the hydrogen atoms
A person shakes up vinegar and oil dressing before pouring it on salads. What is the chemical reason for doing this?
Vinegar contains charged water molecules, while oil is neutral and repels water.
A water molecule (H-0-H) is held together by
two polar covalent bonds
The hydrogen atoms of a water molecule are bonded to the oxygen atom by ___ bonds, whereas neighboring water molecules are held together by ___ bonds.
___ are weak bonds that are not stong enough to hold atoms together to form molecules that are strong enough to form bondswithin and around large molecules
The tendency of water molecules to stick together is reffered to as
Water's surface tension and heat storage capacity is accounted for by its
As ice melts,
hydrogen bonds are broken
Which of the following will contain more heat but has a lower temperature
an Olympic-sized heated indoor swimming pool
A solution with a pH of 7 is
Compared to a solution of pH 3, a solution of pH 1 is
100 times more acidic
Household ammonia has a pH of 12; household bleach has a pH of 13. Which of the following statements about the, is true
The ammonia has 10 times as many H+ ions as the bleach
donates H+ ions when conditions become too acidic
Which of the following statements about acid precipitation is false is false
acid precipitation has little or no effect on soil chemistry
The emission of ___ and ___ are primarily responsible for acid precipitation
nitrogen oxides...sulfur oxides
Which of the following statements about acid precipitation is false
some chemical reactions create electrons; others destroy them
What change is occuring in this figure
chlorine is filling its third electron shell
The hydrogen bonds shown in this figure are each
between an oxygen and a hydrogen atom of different water molecules
always contain carbon
Which of the following statements regarding carbon is false
carbon has the capacity to form polar bonds with hydrogen
You now know that the old cliche 'oil and water don't mix' is true. Why?
Water exhibits polarity and oild does not.
Which of the following statements about the functional groups of organic compounds is false?
All functional groups include a carbon atom of the organis compounds skeleton
Which of the following statements about the monomers and polymers found in living organisms is false?
Monomers are joined together by the process of hydrolysis.
Which of the following statements about dehydration synthesis is false?
Animal digestive systems utilize this process to break down food
The results of dehyrdation synthesis can be reversed by
What is the general function of enzymes within a cell
to speed up chemical reactions
A dissaccharide forms when
two monosaccharides join by dehydration synthesis
Which of the following list contains only polysaccarides
cellulose, starch, glycogen
Foods that are high in fiber are most likely derived from
The storage form of carbohydrates is ___ in animals and ___ in plants
An oil may be converted into a substance that is a solid at room temperature by
adding hydrogens, decreasing the number of double bonds in the molecules.
Which of the following statements regarding the triglyceride molecules is false
triglycerides are part of a signal pathway
Fatty acids with double bonds between some of their carbons are said to be
The development of atherosclerotic disease can result from a diet high in
Which of the following substances is a lipid
Which of the following statements about anabolic steroids is false
they promote bone growth
Which of the following would be correctly classified as a protein
Amino acids can be distinguished from one another by
the chemical properties of their R groups
Glucose molecules are to starch as ___ are to proteins
Proteins cannot be denatured by
Which of the following statements regarding nucleotides is false?
nucleotides have a nitrogenous base base backbone
DNA differs from RNA because DNA
contains thymine in place of uracil
Genetic information is encoded in the
sequence of nucleotides in DNA
These two molecules are structural isomers. What is the difference between them?
the location of a double-bonded oxygen atom.
...which hypothesis is likely to be more productive for their initial investigation
th three-dimensional structure of the proteins may have been altered
based on your understanding of enzyme structure, which of the following would you recommend that they also investigate?
the temperature of the liquid in the washing vat
How are these two amino acids attatched together?
amino group to carboxylic acid group
use light and glass lenses to magnify an image
....which of the following instruments would be best and why?
a light microscope because it allows observation of whole, live cells.
The idea that all living things are composed of cells and that all cells come from other cells defines
...Which one of the following instruments would be best?
scanning electron microscope
A scanning electron microscope is used to study ____, whereas a transmission electron microscope is used to study ____
cell surfaces...internal cell structures
As cell size increases, the
volume increases faster than the surface area
a cell is exposed to a sunstance that prevents it from dividing. The cell becomes larger. this situation
will eventually be problematic, since the cell's ability to absorb nutrients though its outer membrane will not keep increasing as quickly as its cytoplasmic needs
___ cells lack a membrane-inclosed nucleus
The membranes compartmentalization of a cell
allows different metabloic processes to occur simultaneously
..cell walls...and membrane-bound organelles...you can conclude that the cells
are plant cells
Unlike animal cells, plant cells have __ and __. unlike plant cells, animal cells have __
Plasma membranes are permeable to
nonpolar molecules such as CO2
What would you expect to find when looking through a SEM at a cell with an enzyme that cleaves proteins at their hydrophilic amino acids?
a cell surface that is devoid of any major structures
the nucles of a cell
Long fibers of DNA and protein are called
the function of the nucleus is
to manufacture ribosomal RNA
Smooth endoplasmic reticulum
stores calcium ions in muscle cells
The two main functions of the rough endoplasmic reticulum are the production of
membrane and proteins secreted by the cell
the Golgi apparatus
stores, modifies, and packages proteins
Which of the following statements regarding the Golgi apparatus is false?
the Goldi apparatus decreases in size when a cell increases its protein production
Which of the following statements about lysosomes is false
lysosomes synthesize proteins from the recycled amino acids
when a cell is deprived of oxygen, its lysosomes tend to burst and release their contents into the cell. As a result of this, the cell will
undergo self-digestion and die
which of the following statements about the functions of a plant cell central vacuole is false
the central vacuole of the cell may digest chemicals for recycling
prevent cell from bursting as a result of the influx of excess water
Which organelle is involved in the break down of the fatty acids and the detoxification of alcohol