A group of closely related organisms capable of interbreeding to produce fertile offspring are known as members of a

A. kingdom

B. class

C. family

D. species

Viruses are economically important because they

A. do not have cell structures

B. can only reproduce inside living cells.

C. cause diseases in plants and animals

D. exist as crystals outside living cells

A beaker of pond water containing few specimens of Euglena was placed in a dark room for two weeks. At the end of this period, the specimens of Euglena were still alive because they were

A. able to carry out holozoic nutrition.

B. able to carry out photosynthesis using carbon dioxide in the pond water

C. better adapted to life in darkness than to life in light

D. not overcrowded

The cytoplasm of the cell is considered a very important component because it

A. regulates the amount of energy in the cell

B. suspends all cell organelles.

C. is the outermost part of the cell

D. is solely responsible for cell division

After an hour, the level of water in the thistle funnel will

A. rise

B. fall

C. remain the same

D. double

The experiment above is used to demonstrate the process of

A. transpiration

B. water culture

C. diffusion

D. osmosis

In plant cells the role of the membrane is played by the

A. nucleolus

B. cell wall

C. cytoplasm

D. mitochondrion

Red blood cells were found to have burst open after being placed in distilled water for an hour. This phenomenon is known as

A. plasmolysis

B. diffusion

C. haemolysis

D. wilting

The curvature movement of plants in response to the stimulus of water is called

A. hydrotropism

B. geotropism

C. phototropism

D. thigmotropism

Two organelles directly involved in mitotic cell division are

A. nucleus and mitochondrion

B. ribosome and nucleus.

C. centriole and Golgi apparatus

D. nucleus and centriole

The following statements about mitotic cell division are correct except that

A. it occurs only in young cells

B. it occurs In somatic cells

C. the chromosome number of the daughter cell is the same as that of the parent

D. the genetic composition of the mother cell is the same as that of the daughter cell.

The longest bone in the body is the

A. humerus

B. femur

C. scapula

D. tibia