PLTW Biomed Midterm Review UPDATED
Exam Questions and CORRECT Answers
Why does blood clump? - CORRECT ANSWER - due to the antibody binding to the
antigen. antibodies are specific to each antigen so only B antibodies will bind with B antigens
What are the four blood types? - CORRECT ANSWER - O, A, B, AB
What evidence from a crime scene would contain DNA? - CORRECT ANSWER - blood,
hair, skin, and saliva
What are the three main types of fingerprints? - CORRECT ANSWER - arch, loop, and
whorl
What are ridge endings and bifurcations? - CORRECT ANSWER - parts of fingerprint
classification
What is rigor mortis? - CORRECT ANSWER - rigor mortis- tightening of the muscles
after death
What is Etomology? - CORRECT ANSWER - Etomology- study of bugs and when they
arrive after death
What is lividity? - CORRECT ANSWER - lividity- blood pooling
What is algor mortis? - CORRECT ANSWER - algor mortis- internal temperature cooling
What are some factors that affect algor mortis? - CORRECT ANSWER - clothing, original
internal temp, ambient temperature, environment, and body size
, What are null hypotheses? - CORRECT ANSWER - null hypothesis- a hypothesis that
assumes everything will stay the same (caffeine will have no effect on blood sugar)
what are alternative hypothesis? - CORRECT ANSWER - alternative hypothesis- a
hypothesis that describes the outcome that is predicted (caffeine will affect blood sugar)
What is standardization? - CORRECT ANSWER - each group should have the same
conditions as each other except for the independent variable (each group should have the same
type of diabetes, same diet, and same physical activity)
What are negative and positive control? - CORRECT ANSWER - negative control-
nothing should happen to this group (people without caffeine)
positive control- a group used to show what a positive result looks like
What affects blood spatter stains? - CORRECT ANSWER - force, height, amount of
blood, angle, objects in the way, and how close the victim is to the perpetrator.
What shape does a blood stain have that falls directly from above? - CORRECT
ANSWER - perfect circle
What is DNA? What shape is it in? What is it made of? - CORRECT ANSWER - DNA
stands for deoxyribose nucleic acid and it is the type of nucleic acid that requires deoxyribose
sugar. It's in the shape of double helix. made of nucleotides.
What are nitrogenous bases? - CORRECT ANSWER - they connect the two strands of the
DNA together and found in the middle of the DNA molecule
What are the 4 nitrogenous bases and what are purines and pyrimidines? - CORRECT
ANSWER - purines- have two rings (Adenine, Guanine)
pyrimidines- have one ring (Cytosine, Thymine)
A pairs with T and have two hydrogen bonds
Exam Questions and CORRECT Answers
Why does blood clump? - CORRECT ANSWER - due to the antibody binding to the
antigen. antibodies are specific to each antigen so only B antibodies will bind with B antigens
What are the four blood types? - CORRECT ANSWER - O, A, B, AB
What evidence from a crime scene would contain DNA? - CORRECT ANSWER - blood,
hair, skin, and saliva
What are the three main types of fingerprints? - CORRECT ANSWER - arch, loop, and
whorl
What are ridge endings and bifurcations? - CORRECT ANSWER - parts of fingerprint
classification
What is rigor mortis? - CORRECT ANSWER - rigor mortis- tightening of the muscles
after death
What is Etomology? - CORRECT ANSWER - Etomology- study of bugs and when they
arrive after death
What is lividity? - CORRECT ANSWER - lividity- blood pooling
What is algor mortis? - CORRECT ANSWER - algor mortis- internal temperature cooling
What are some factors that affect algor mortis? - CORRECT ANSWER - clothing, original
internal temp, ambient temperature, environment, and body size
, What are null hypotheses? - CORRECT ANSWER - null hypothesis- a hypothesis that
assumes everything will stay the same (caffeine will have no effect on blood sugar)
what are alternative hypothesis? - CORRECT ANSWER - alternative hypothesis- a
hypothesis that describes the outcome that is predicted (caffeine will affect blood sugar)
What is standardization? - CORRECT ANSWER - each group should have the same
conditions as each other except for the independent variable (each group should have the same
type of diabetes, same diet, and same physical activity)
What are negative and positive control? - CORRECT ANSWER - negative control-
nothing should happen to this group (people without caffeine)
positive control- a group used to show what a positive result looks like
What affects blood spatter stains? - CORRECT ANSWER - force, height, amount of
blood, angle, objects in the way, and how close the victim is to the perpetrator.
What shape does a blood stain have that falls directly from above? - CORRECT
ANSWER - perfect circle
What is DNA? What shape is it in? What is it made of? - CORRECT ANSWER - DNA
stands for deoxyribose nucleic acid and it is the type of nucleic acid that requires deoxyribose
sugar. It's in the shape of double helix. made of nucleotides.
What are nitrogenous bases? - CORRECT ANSWER - they connect the two strands of the
DNA together and found in the middle of the DNA molecule
What are the 4 nitrogenous bases and what are purines and pyrimidines? - CORRECT
ANSWER - purines- have two rings (Adenine, Guanine)
pyrimidines- have one ring (Cytosine, Thymine)
A pairs with T and have two hydrogen bonds
