Cells 1 Practice Test

The portion of the membrane system in eukaryotic cells that is responsible for the making lipids and breaking down toxic substances is the

• rough ER

• smooth ER

• ribosomal ER

• semi-permeable ER

The cell membrane forms a protective barrier between the external and internal environments. It is referred to as ___________________, because it allows some substances to cross more easily than others and blocks other substances from crossing into the cell.

• impermeable

• a fluid mosaic

• selectively permeable

• a plasma membrane

To maintain turgor pressure, cells in both the leaves and stems of most non-woody or herbaceous plants contain

• chloroplasts

• starch granules

• many mitochondria

• a large central vacuole.

In prokaryotic and eukaryotic cells the amount of water in the cell is kept at a steady state. The organelles through which water passes into and out of cell is the

• cell membrane

• cell wall

• nucleus

• ribosome

Both prokaryote and eukaryote cells have this structure. It helps maintain homeostasis and is a boundary between the inside of the cell and the outside environment. It is the

• nucleus.

• membrane.

• cytoplasm.

• cell wall.

What is the function of the cell membrane?

• to give shape to the cell

• to increase the number of cells

• to control what enters and leaves the cell

• to produce macromolecules within the cell

All living things need energy; it is a requirement for life. In a typical cell, ATP, the high energy molecule, is produced in the __________ in the presence of a sugar (glucose) and ______________.

• nucleus; oxygen

• ER; carbon dioxide.

• mitochondria; oxygen.

• vacuole; water vapor.

According to the law of conservation of matter, matter is never created or destroyed. Yet in a food pyramid the amount of biomass decreases as we move up through the pyramid, from producers to top level consumers. Why?

• Matter is decomposed at different levels in a food chain.

• Matter is recycled at each level of the food chain and returned back to the producers.

• Matter is taken back by the producers after it is left unused by consumers at each level.

• Matter changes to other forms that might not continue to be a part of the same food chain.

The graph above was made by a South American biologist in the country of Brazil, after a long study on parrots. About 200 years ago, 90% of Brazil was covered in mature, deep forest. Today, well over half of this forest has been cut to make way for farms. What conclusion could you draw about the parrots in the graph?

• Red parrots have become less common in the last 200 years.

• There are probably less green parrots today than there once were.

• Blue parrots probably are the best adapted species to live on farms.

• The blue parrot population has likely increased in the last 200 years.

Fertilizers have nutrients that help plants grow. Sometimes, when it rains, fertilizers are washed away from farmland into ponds and lakes. This promotes the growth of algae, a type of plant, present in the water. It is observed that algae grow very fast and cover the surface of the pond completely. They use up all the dissolved oxygen in the pond. How does this affect the other organisms in the pond?

• They start eating algae.

• They do not get enough oxygen, and die.

• They get entangled in the algae, and die.

• They leave the pond and go to live elsewhere.