USAT-M MCQs

An element cannot be broken down chemically into simpler substances.
Each element is identified by its atomic number.

Compounds have definite formulas and characteristic properties.
Their components can be separated only by chemical means.

Mixture components retain much of their individual identity.
They can often be separated by physical methods.

Solutions are homogeneous mixtures.
Any sampled portion has approximately the same composition.

Heterogeneous mixtures contain distinguishable regions or phases.
Examples include sand in water and granite.

A physical change alters form or state without changing chemical identity.
Ice and liquid water are both H2O.

All organisms are made of one or more cells.
Cells perform the fundamental processes required for life.

Modern cell theory states that cells come from existing cells.
Cell division provides continuity of life.

The plasma membrane is selectively permeable.
It regulates exchange between the cell and its environment.

Phospholipids form a bilayer with hydrophilic heads and hydrophobic tails.
Proteins and other molecules are embedded within it.

Membrane components can move laterally within the bilayer.
The membrane is flexible rather than rigid.

A vector has both magnitude and direction.
Acceleration describes the rate and direction of velocity change.