Exam 1 BSC 2010

What is the hydroxyl ion (OH^-) concentration of a solution of pH 8?

10^-6

The atomic number of nitrogen is 7. Nitrogen-15 has a greater mass number than nitrogen-14 because the atomic nucleus of nitrogen-15 contains

15 protons

Which component in the accompanying figure is a protein fiber of the extracellular matrix?

A

Prokaryotic cells lack

A nucleus and other organelles

The plasma membrane is a semipermeable membrane. This means that it is

A polymeric membrane that will allow certain molecules or ions to pass though it by diffusion

In a bottle of water, hydrogen bonding occurs between the hydrogen of one atoms and a/an

An oxygen atom of a different water molecule.

Five dialysis bags constructed if a type of membrane that is impermeable to sucrose, were filled with various concentrations of sucrose and then placed in separate beakers containing an initial concentration of 0.6 M sucrose solution. At 10-minute intervals the bags were massed and the percent change in mass of each bag was graphed. Which line or lines in the graph represent bags that contain a solution that is hypertonic at 50 minutes?

B. Second line 0

Why is a stem burn more severe than a hot water burn

Because of the latent heat vaporization

Facilitated diffusion is similar to simple diffusion because

Both involve movement down the concentration gradient

Which of the following could be responsible for atherosclerosis and should be eliminated from diet for health reasons ?

Butter, liver, and kidney organ meat

Which of the following illustrations is not a structural isomer of an organic compound with the molecular formula C6H14? For clarity only the carbon skeletons are shown, hydrogen atoms that would be attached to the carbons have been omitted.

C. C-C=C-C | | C C

The large central vacuole of plants

Central vacuole mainly contains water.

Which of the following is a function of the nucleus?

Controls and regulates the activities of the cell and carries the genes, structures that contain the hereditary info.

A carbon atom is most likely to form what kind of bonds with other atoms?

Covalent bond

Cells that are infected, damaged, or have reached the end of their function life span often undergo "programmed cell death"? The controlled cell suicide is called apoptosis, select the appropriate description of this event on a cells life cycle.

During apoptosis, cellular agents chop up the DNA and fragment the organelles and other cytoplasm components of a cell

Every protein has a unique shape and function because

Each protein has a unique sequence of amino acids

The figure shows the branching tree of life for bears. Which bear species is most distantly related to the sun bear?

Giant panda

Low humidity in the atmosphere on a hot day

Helps in cooling because water evaporates from the skin faster.

The membranes of winter wheat are able to remake fluid when it is extremely cold by

Increasing the percentage of unsaturated phospholipids in the membrane

Celery stalks that are immersed in fresh water for several hours become stiff. Similar stalks left in a 0.15. M salt solution become limp. From this we can deduce that the fresh water

Is flowing into the cells, thereby increasing tutor pressure inside of them.

The naturally occurring helium atom is chemically inert because

It's outermost shell is filled with ekectrons

Asbestos is a material that was once used extensively in construction. One risk from working in a building that contains asbestos is the development of asbestosis caused by the inhalation of asbestos fibers. Cells will take up asbestos by phagocytosis, but are not able to degrade it. As a result, asbestos fibers accumulate in

Lysosomes

Which organelle is the primary site of ATP synthesis in eukaryotic cells?

Mitochondria

Which structure is a common to plant and animal cells?

Mitochondrion

Which of the following statements is true for lipids?

Most are simply polymers of isoprene

Which of the following would form the fewest covalent bonds?

Neon (eight electrons in the second shell)

Bonds between two atoms that are equally electronegative are

Non polar covalent bonds

Examine the structure of the plant in the cell figure. Which organelles connects to the endoplasmic reticulum?

Nuclear envelope

Nucleotides are the building blocks for

Nucleic acids

In receptor mediated endocytosis receptor molecules initially project to the outside of the cell. Where do they end up after endocytosis ?

On the inside surface if a vesicle

The term that describes the diffusion of water is

Osmosis

A localized group of organism that belong to the same species is called a

Population

Hydrogen bonds are very important in the functional shape of

Proteins and nuclei acids

Alpha helices and beta pleated sheets are examples of

Secondary structures held in shape by hydrogen bonds

To act as an effective coolant in a cars radiator a substance has to have the capacity to absorb a great deal of heat. You have a reference book with tables listing the physical properties amor many liquids. In choosing a coolant for you car, which table would you check first?

Specific heat

The figure shows the structures of glucose and fructose. These two molecules are

Structural isomers

What makes lipids/fats hydrophobic?

The Non polar C-H bonds in the hydrocarbon chains of the fatty acids make fats hydrophobic

Cells are

The basic building blocks of all living things

The force driving simple diffusion is .........., while the energy source for active transport is ...........

The concentration gradient, ATP

The data below show the distribution of types of fats found in three different food products. What can you conclude from these data?

The majority of the fats in corn oil have double bonds

If you transferred a phospholipid bilateral from water to oil, what effect would this have on the membrane?

The membrane is expected to invert its normal structure such that the polar head groups hide inside the bilayer and the non polar fatty acid tails face out to the oil.

If you could add a colored label to one phospholipids in the cells plasma membrane to observe this molecule what kind of movement of the molecule would you see?

The molecule would move rapidly back and forth across the surface of the membrane

For an atom to be considered an ion

The number of protons may outnumber the number of electrons

Spherocytosis Is a human look disorder associated with a defective cytoskeleton protein in the red blood cells. What do you suspect is the consequence of such a defect?

The shape is abnormal

A newspaper ad for a local toy store indicated than an inexpensive toy microscope available for a small child is able to magnify specimens nearby as much as the more costly microscope available in your college lab. What is the primary reason for the price difference ?

The toy microscope magnifies a good deal, but has a low resolution and therefore poor quality images.

What is the difference between a tissue and an organ system?

Tissues are a group of cells with similar structures working together to perform a shared function. Organs are structures made up of a group of tissues working together to perform specific functions.