Exam 1
Which statement would you agree with?
science has room for different views among scientists
A biologist wants to test the effectiveness of a new food additive on causing growth on mice. An effective control group would be one that:
was fed the same ration without the food additive
All of the following are properties of water EXCEPT
water speeds up metabolism
To distinguish between prokaryotes and eukaryotes, we need to consider:
whether the genetic information is enclosed in a protective layer of phospholipid membrane bilayer
Which source of carbohydrates will be digested the slowest?
whole wheat bread
Whether something is alive is best determined by:
Presence of multiple characteristics of life
The formulation of hypotheses represents a critical step in the scientific process. In the simplest terms, what is a hypothesis?
an explanation
The scientific method is used to:
answer specific questions about the natural world
Which answer below will provide all of the essential amino acids in a meal?
hamburger, corn and beans
What is the characteristic of life that allows living organisms to maintain a relatively constant environment/internal equilibrium despite inevitable external changes?
homeostasis
The variable that in an experiment is under the control of the researcher is called
independent variable
Atoms that bear a positive or negative charge are known as:
ions
The most common atom in the atmosphere is:
nitrogen
Which one of the following would most biologists consider to be alive?
present in: DNA, uses energy, growth, reproduces absent in: mobility
Enzymes (also known as catalysts) are macromolecule that belong to the _____________ category
proteins
The cell theory proposes that all living organisms are made of cells
true
The substance that dissolves almost anything in it is called the solvent
true
What makes viruses unique among other living organisms when it comes to reproduction?
viruses reproduce only inside other cells
Although planet earth is 75% covered by water, only _______ % constitutes the usable volume available to fulfill the needs of living beings.
.5%
Which of the following best describes the structure of the cell membrane
A double layer of lipids with proteins embedded in it
Why does water display the unique properties we have been learning so far?
Because of its ability to form hydrogen bonds.
Why food production consists ultimately in "farming the sun?"
Because the sun triggers photosynthesis in plants.
Atoms are the smallest units of matter. Who first coined this term?
Democritus
Which of the following statements is a testable, scientific hypothesis?
Eating fish reduces the chances of getting a stroke
Consider an experiment in which subjects are given a pill to test its effectiveness on reducing the duration of a cold. Which of the following is the best way to treat the control group?
Give the control group a pill that does not affect colds
Which statement is true when comparing lemon juice (acidic) to baking soda (basic)?
Lemon juice has more H+ compared to baking soda.
For many centuries the theory of spontaneous generation explained how life began however, it was eventually proven incorrect in the 19th century by whom?
Louis Pasteur
The beaches at a nearby lake have been closed because of high E. coli counts. The lake is surrounded by agricultural areas and summer cottages. We know that different species of vertebrates have different E. coli strains in their digestive tracts. Which of the following represents an HYPOTHESIS for the source of the high E. coli counts?
Runoff from dairy farms causes high E. coli counts
Which of the following is support for the theory of evolution which states that all life on Earth arose from a common ancestor?
a. All life on Earth shares a common organic chemistry a. All life on Earth has the same genetic material b. All life on Earth has the same basic cellular structures c. All life on Earth performs the same basic metabolic processes
Statistical analysis of experimental data determines................................what?
a. the amount of bias in the experimental design b. the likelihood that the results are due to the experimental treatment c. whether the experiment proves that the hypothesis being tested is correct d. whether the proper controls were used in the experiment
Scientists are often hesitant to believe the results of a single experiment testing a particular treatment, even when the results are peer-reviewed and statistically significant. This is because:
a. the experimental and control groups may not have been as alike as possible b. if the experiment used a model organism, the results may not be true for humans c. a single experiment may not have eliminated many alternate hypotheses d. unintentional biases may have affected the results of the experiment
The pH of a water solution is 4.77 This solution is:
acidic
Which of the following is NOT an essential atom to support life among living cell?
aluminum
The first living organisms to inhabit Earth about 3.5 billion years ago were:
bacteria
. Heart disease results from plaque narrowing or blocking blood vessels in the muscle tissue of the heart. For decades scientists have believed that heart disease is caused by stress, genetics and poor diet. A new hypothesis is that the infectious bacteria C. pneumonia causes heart disease. Which of the following observations would strongly support the new hypothesis that bacteria cause heart disease? People with...
blocked blood vessels have high levels of bacteria and plaque-free blood vessels have no bacteria
All plant cells possess a unique organelle and this is the___________, which is necessary for them to do photosynthesis:
chloroplast
Ideally, an experiment studying the effect of a cold medicine should have
control group, large sample size, subjects randomly assigned to experimental and/or control group, uses a placebo
If you were going to build a large macromolecule or polymer it needs to be strong. What type of chemical bond do you think would work best for building macromolecules?
covalent
Which of the following is a scientific hypothesis?
d. People catch colds because of exposure to cold temperature
All eukaryotes possess a cell wall
false
Darwin's theory of evolution supports the idea that species do not change over time
false
Photosynthesis is the chief metabolic reaction among animal cells.
false
Sugars like glucose are the molecules that provide energy needed by cells to do work.
false
The first step of the scientific process consists in making a prediction of a natural phenomenon
false
Results from one test of a new drug are found to be statistically significant; thus the hypothesis
should be tested again
Certain protein molecules act as enzymes and thus, speed up metabolic reactions within cells
true
Glucose (C6H12O6) is the most common simple sugar in nature
true
Glycogen is a complex carbohydrate that is stored in the cells of the liver
true
Phospholipids are the typical fats that line biological membranes
true