PAX Prep Science Exam Questions and
answers 2025
1 .kilogram .of .solid .X .at .10 .Celsius .and .1 .kilogram .of .solid .Y .at .10 .Celsius .each
.absorbs .5 .joules .of .heat .energy. .The .final .temperatures .of .X .and .Y .are .15 .Celsi
us .and .20 .Celsius, .respectively. .Compared .to .X, .Y .must .have .a .lower .- .ANS✓✓-
-specific .heat*
-conductive .heat
-heat .of .fusion
-heat .of .vaporization
A .drop .of .dilute .ammonium .hydroxide .is .placed .on .one .side .of .a .slide .containi
ng .a .large .number .of .swimming .paramecium. .Under .this .condition, .which .of .th
ese .behaviors .of .the .paramecia .will .be .observed? .- .ANS✓✓--
they .will .eventually .all .swim .toward .it
-they .will .show .no .net .change .in .behavior
-they .will .be .instantly .killed
-they .will .eventually .all .swim .away .from .it*
A .person .blows .his .breath .into .a .straw .that .is .placed .in .limewater. .The .limewat
er .becomes .cloudy .because .the .person's .breath .contains .- .ANS✓✓--
carbon .dioxide*
-hydrogen
-oxygen
-nitrogen
A .student .focuses .sunlight .to .a .point .with .a .thin .converging .
(convex) .lens. .Which .of .these .direct .measurements .can .the .student .make .as .a .
result .of .this .experiment? .- .ANS✓✓--approx. .focal .length .of .the .lens**
-approx. .wavelength .of .the .light .used
-approx. .speed .of .light
-approx. .index .of .refraction .of .the .lens .material .(incorrect)
An .unknown .gas .is .more .dense .than .air, .does .not .support .combustion, .and .tur
ns .a .limewater .solution .cloudy. .This .gas .is .most .probably .- .ANS✓✓--ammonia
-methane
-carbon .dioxide*
-hydrogen
Guard .cells .which .can .be .found .in .the .leaves .of .plants .are .most .closely .associ
ated .with .which .of .these .processes? .- .ANS✓✓--reproduction .of .a .new .plant
, -evaporation .of .water .from .the .plant*
-synthesis .of .organic .substances .in .the .plant
-movement .of .organic .and .inorganic .substances .from .soil .to .the .plant
Human .testes .produce .- .ANS✓✓--eggs
-follicle .stimulating .hormone .(incorrect)
-growth .hormone
-spermatozoa**
In .diagnostic .testing, .the .electroencephalogram .permits .the .physician .to .- .ANS
✓✓--examine .the .impulses .of .the .specialized .muscle .cells .of .the .heart
-examine .the .impulses .of .the .nerve .cells .within .the .brain*
-measure .the .pressure .within .the .eye
-measure .the .amount .of .air .upon .exhalation
To .sterilize .a .metal .probe .in .the .office, .a .dentist .could .use .a .steam .sterilizer. .If .
unavailable, .the .next .most .effective .method .to .sterilize .the .instrument .would .be
.- .ANS✓✓--boiling .it .in .water .for .15 .minutes*
-dipping .it .into .a .concentrated .acid .solution
-heating .it .in .a .hot .air .oven .at .160C .for .20 .mins
-washing .it .in .soap .and .water
In .varieties .of .matter, .the .term .heterogeneous .may .be .applied .to .- .ANS✓✓--
elements, .but .not .compounds .(incorrect)
-compounds, .but .not .elements
-compounds .and .elements, .but .not .mixtures
-mixtures, .but .not .elements .or .compounds**
Iodized .salt .is .used .to .prevent .a .human .condition .known .as .- .ANS✓✓--rickets
-goiter*
-scurvy
-beri-beri
The .atoms .of .an .element .with .seven .valence .electrons .are .most .probably .classi
fied .as .- .ANS✓✓--metals .(incorrect)
-nonmetals
-metalloids
-noble .gases
The .process .of .nuclear .cell .division .in .the .cell .reproduction .of .plants .differs .fro
m .mammals. .A .major .difference .is .that .- .ANS✓✓--
homologous .chromosomes .are .paired .(incorrect)
-centrioles .are .replicated .
-spindle .fibers .are .missing
-cell .plates .are .synthesized
Unicellular .organisms .that .have .a .nucleus .and .can .swim .with .the .aid .of .cilia .ar
e .examples .of .- .ANS✓✓--monerans
-plants
answers 2025
1 .kilogram .of .solid .X .at .10 .Celsius .and .1 .kilogram .of .solid .Y .at .10 .Celsius .each
.absorbs .5 .joules .of .heat .energy. .The .final .temperatures .of .X .and .Y .are .15 .Celsi
us .and .20 .Celsius, .respectively. .Compared .to .X, .Y .must .have .a .lower .- .ANS✓✓-
-specific .heat*
-conductive .heat
-heat .of .fusion
-heat .of .vaporization
A .drop .of .dilute .ammonium .hydroxide .is .placed .on .one .side .of .a .slide .containi
ng .a .large .number .of .swimming .paramecium. .Under .this .condition, .which .of .th
ese .behaviors .of .the .paramecia .will .be .observed? .- .ANS✓✓--
they .will .eventually .all .swim .toward .it
-they .will .show .no .net .change .in .behavior
-they .will .be .instantly .killed
-they .will .eventually .all .swim .away .from .it*
A .person .blows .his .breath .into .a .straw .that .is .placed .in .limewater. .The .limewat
er .becomes .cloudy .because .the .person's .breath .contains .- .ANS✓✓--
carbon .dioxide*
-hydrogen
-oxygen
-nitrogen
A .student .focuses .sunlight .to .a .point .with .a .thin .converging .
(convex) .lens. .Which .of .these .direct .measurements .can .the .student .make .as .a .
result .of .this .experiment? .- .ANS✓✓--approx. .focal .length .of .the .lens**
-approx. .wavelength .of .the .light .used
-approx. .speed .of .light
-approx. .index .of .refraction .of .the .lens .material .(incorrect)
An .unknown .gas .is .more .dense .than .air, .does .not .support .combustion, .and .tur
ns .a .limewater .solution .cloudy. .This .gas .is .most .probably .- .ANS✓✓--ammonia
-methane
-carbon .dioxide*
-hydrogen
Guard .cells .which .can .be .found .in .the .leaves .of .plants .are .most .closely .associ
ated .with .which .of .these .processes? .- .ANS✓✓--reproduction .of .a .new .plant
, -evaporation .of .water .from .the .plant*
-synthesis .of .organic .substances .in .the .plant
-movement .of .organic .and .inorganic .substances .from .soil .to .the .plant
Human .testes .produce .- .ANS✓✓--eggs
-follicle .stimulating .hormone .(incorrect)
-growth .hormone
-spermatozoa**
In .diagnostic .testing, .the .electroencephalogram .permits .the .physician .to .- .ANS
✓✓--examine .the .impulses .of .the .specialized .muscle .cells .of .the .heart
-examine .the .impulses .of .the .nerve .cells .within .the .brain*
-measure .the .pressure .within .the .eye
-measure .the .amount .of .air .upon .exhalation
To .sterilize .a .metal .probe .in .the .office, .a .dentist .could .use .a .steam .sterilizer. .If .
unavailable, .the .next .most .effective .method .to .sterilize .the .instrument .would .be
.- .ANS✓✓--boiling .it .in .water .for .15 .minutes*
-dipping .it .into .a .concentrated .acid .solution
-heating .it .in .a .hot .air .oven .at .160C .for .20 .mins
-washing .it .in .soap .and .water
In .varieties .of .matter, .the .term .heterogeneous .may .be .applied .to .- .ANS✓✓--
elements, .but .not .compounds .(incorrect)
-compounds, .but .not .elements
-compounds .and .elements, .but .not .mixtures
-mixtures, .but .not .elements .or .compounds**
Iodized .salt .is .used .to .prevent .a .human .condition .known .as .- .ANS✓✓--rickets
-goiter*
-scurvy
-beri-beri
The .atoms .of .an .element .with .seven .valence .electrons .are .most .probably .classi
fied .as .- .ANS✓✓--metals .(incorrect)
-nonmetals
-metalloids
-noble .gases
The .process .of .nuclear .cell .division .in .the .cell .reproduction .of .plants .differs .fro
m .mammals. .A .major .difference .is .that .- .ANS✓✓--
homologous .chromosomes .are .paired .(incorrect)
-centrioles .are .replicated .
-spindle .fibers .are .missing
-cell .plates .are .synthesized
Unicellular .organisms .that .have .a .nucleus .and .can .swim .with .the .aid .of .cilia .ar
e .examples .of .- .ANS✓✓--monerans
-plants
