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