Bio Unit 1 - Chemistry & The Cell/Organic Compounds (Some of the Questions)

A 2.50 liter aqueous solution contains 1.25 moles of dissolved sodium. Determine the molarity of this solution.

0.5M

What is the molarity of a solution that contains 0.500 mole of KNO3 dissolved in 0.500 liter of solution

1.00M

A 2.0 liter aqueous solution contains a total of 3.0 moles of dissolved NH4Cl at 25°C and standard pressure. Determine the molarity of the solution.

1.5M

Plants that live in hot, dry climates have evolved mechanisms to help conserve limited water supplies. One example is the closing of lead openings by guard cells during the day to decrease water loss for, their leaves. This detection of and response to an environmental stimulus is an example of

A feedback mechanism

Mad Cow disease is a fatal disease that destroys brain tissue. Researchers have found that a prion protein. Which is an abnormally constructed molecule, is responsible. Which statement best describes the characteristics a protein must have to function correctly?

A protein is a long chain of amino acids folded into a specific shape

What is the process used when a complex sugar (polymer) becomes a simple sugar (monomer)?

Digestion

If a starch-digesting enzyme were added to a sports gel that lists starch as an ingredient, which substance would increase in concentration?

Glucose

Dynamic Equilibrium

Homeostasis

Which statement best describes some protein molecules in a cell?

Proteins are long, folded chains that can form various cell parts

In response to an increasing blood glucose level, the human body will normally

Release a hormone that lowers the blood glucose

Which change is an example of a response to a stimulus?

The pupil of an eye decreases in size in bright light

Which statement is most likely correct regarding soil bacteria that inhabit the polar regions of Earth?

They contain enzymes that function at low temperatures

Inorganic Molecules

Water (H2O), Carbon Dioxide (CO2), Oxygen (O2), Nitrogen (N2)

Homeostasis

a balance in an organism's body which is needed to live

Insulin

a hormone that moves sugar out of blood

Energy drinks have become increasingly popular. Some of these drinks contain large amounts of caffeine, which is known to increase heart rates in most individuals. This effect on the heart rate can be dangerous because it can lead to

an imbalance in homeostasis

A protein chain unfolds and stops functioning. Why does the chain unfold?

an internal factor in the body, such as a temperature increase

In living cells, chemical processes, such as synthesis, all require the action of

biological catalysts

Cellular Respiration

convert energy in food into a usable form (ATP)

Feedback Mechanism

cycles where one reaction causes another to occur (used to maintain homeostasis)

When the pH of an aqueous solution is changed from 1 to 2 the concentration of hydronium Ions in the solution is

decreased by a factor of 10

Like humans, animals including dogs and cats get goose bumps. On a cold day, these goose bumps cause their coats to expand creating a layer of insulation. If the animal is scared, the coat will also expand making the animal look larger to predators. These responses serve as examples of

detection and response to stimuli

In humans, the maintenance of a stable internal temperature is a direct result of

detection of and reaction to stimuli in the environment

Organisms contain compounds such as proteins, starches and fats. The chemical bonds in these compounds can be a source ofz

energy

The shape of a protein molecule directly determines its

functions inside and outside of cells

An energy-rich organic compound needed by organisms is

glucose

Using blood coping to artificially increase the number of red blood cells in an athlete might lead to a long-term shortage of red blood cells because

homeostasis could be disrupted in the athlete

The energy in a molecule is stored

in the bonds between atoms

When the concentration of hydrogen ions in a solution is decreased by a factor of ten, the pH of the solution

increases by 1

When the pH of a solution is changed from 4 to 3, the hydronium ion concentration of the solution

increases by a factor of ten

Which change is an example of maintaining dynamic equilibrium?

insulin is released when glucose levels in the blood are high

Increased concern over the number of heat-related illness among football players has led to a possible change in uniform design. Shoulder pads were designed that constantly blew cool, dry air underneath the shoulder pads. Test showed that the use of the device during rest and recovery periods resulted in a reduction of body temperature and heart rate. This new device would help to athlete to

maintain homeostasis

When the human body is responding to stress, the hormone adrenaline is released. A short time later, the body returns to normal. This is an example of how a human

maintains dynamic equilibrium

What are the 7 life processes?

nutrition, cellular respiration, synthesis, transport, regulation, excretion, reproduction (reproduction is not necessary to maintain homeostasis)

Proteins, starch and DNA are similar in that they are all

organic compounds

Pancreas

produces insulin

Which group consists entirely of organic molecules?

protein, starch, fat

Organic compounds are used as building blocks for

proteins, starches and fats

A catalyst increases the rate of a chemical reaction by

providing an alternate reaction pathway

During periods of vigorous physical activity, a person's breathing and heart rates increase. This enables the cells of the body to perform more efficiently because it helps the cells to

remove waste products faster

Which life function is not necessary for an individual organism to stay alive?

reproduction

Even though human proteins are synthesized from only 20 different amino acids, there are thousands of different proteins found in human cells. This great variety of proteins is possible because the

sequence and number of amino acids can be different in each protein

A fully functioning enzyme molecule is arranged in a complex three-dimensional shape. This shape determines the

specific type of molecule it interacts with during a reaction

Carbohydrates

sugars and starches