18 CELLS. 
What vital phenomena are common to all protoplasm ? 
The absorption of and combination with oxygen, the production of 
carbon dioxide and other products of oxidation. 
What are the results of these changes ? 
Heat is produced and cells perform their individual functions. 
How is the vitality of protoplasm sustained ? 
Living protoplasm possesses the chemical property of being able to 
assimilate and convert into its own substance non-living proteid 
taterial. 
Describe the power of motion possessed by living protoplasm. 
The protoplasm of some cells, notably that of white bloodcells, shows 
changes of form. 
This change is called ameboid motion and is accomplished by a 
budding out of the protoplasm in one or more places. These pro- 
trusions may be withdrawn, or the mass of protoplasm may flow along 
one particular elongation, and so transfer its bulk to that particular 
spot. . 
Describe and give structure of the nucleus. 
It is a small vesicular body embedded in cell protoplasm, and is sur- 
rounded by a homogeneous envelope called the nuclear membrane. 
This encloses the nuclear contents. 
What are the nuclear contents ? 
-They are of two kinds—the formed, made up of threads or fibres, called 
the intra-nuclear network, and the amorphous, which is supposed to 
be of a fluid nature. 
What is the function of the nucleus ? ; 
It is concerned in the reproduction and division of cells. 
What is the nucleolus ? 
It is a small shining globule or vesicle frequently found in nuclei. 
Of its nature and significance we have no definite knowledge. 
What is cell-wall ? 
It is a limiting membrane possessed by a few animal cells and by 
all vegetable cells. It seems to be made up of altered cell-protoplasm. 
In what two ways do cells multiply ? 
By direct and indirect division of nuclei. 
