PLTW BIOMEDICAL SCIENCE LEVEL 2 GRADED A+
REVISED EXAM 2025/2026 Q&A
What is a medical intervention? - Any measure whose purpose is to improve health or alter the
course of a disease
What are the main categories of interventions that function to maintain human health? - Treatments,
Diagnostics and Equipment
How do scientists gather evidence during the potential outbreak of an infectious disease? - 1. Record
patient's symptoms and find similarities with other patients
2. Isolate the bacteria in a lab
3. Go to affected areas and determine the origin of the disease
4. Identify the disease using DNA sequencing since pathogens alter certain DNA sequences
What is bioinformatics? - The collection, classification, storage, and analysis of biochemical and
biological information using computers. (Especially applied in molecular genetics and genomics)
How can DNA sequences be used to identify disease pathogens? - You can observe mutations and
abnormalities that disease pathogens have
What is an antibody? - A blood protein in the body produced by B-cells (B-Lymphocytes) that fight
against a foreign substance by recognizing a specific part of it.
How do antibodies identify and inactivate antigens? - 1. Shape recognition
2. Proteins of the antigens are configured to specific antibodies, so the foreign antigens bind to the
specific antibodies that inactivate them
How can the ELISA assay be used to detect disease? - 1. Primary antibodies attach to specific antigen
2. Secondary antibody attaches to primary antibody
3. When enzyme substrate is added, color change occurs
Why is it important for doctors to know the concentration of the disease antigen present in a
patient's system? - Higher concentration = closer to patient zero
, Patient Zero - The first person to be infected with a particular disease
What steps do scientists take to diagnose, treat, and prevent future spread of a disease outbreak? -
1. Record the symptoms
2. Locate the origin of the pathogen
3. Run tests to determine antibodies and antigens
4. Take preventative measures (quarantine, wash hands often, etc.)
How were the following used in managing the outbreak on Sue Smith's campus:
PCR, Bioinformatics/BLAST, and ELISA? - These tests determine the concentration of the disease,
which lead to the source of the outbreak
Which part of the bacterial cell allows the bacteria to attach to specific surfaces? - Adhesins, or cell-
surface components/appendages of the bacteria that facilitate attachment to other cells or surfaces
Which bacterial structure is involved with protein synthesis? - rRNA, tRNA, and mRNA (Ribosomal,
Transfer, Messenger)
What is an endotoxin? - A toxin that is inherently present inside a bacterial cell
What is the structural difference between Gram positive and Gram negative bacteria? - Gram
positive:
•Purple
•Thick cell wall
Gram negative:
•Pink
•Thin cell wall
How do antibiotics work to fight bacteria? - •Inhibit the cell wall
•Stop bacteria from reproducing/sharing resistant DNA
Penicillin - An antibiotic that penetrates and destroys the cell wall of gram negative bacteria
REVISED EXAM 2025/2026 Q&A
What is a medical intervention? - Any measure whose purpose is to improve health or alter the
course of a disease
What are the main categories of interventions that function to maintain human health? - Treatments,
Diagnostics and Equipment
How do scientists gather evidence during the potential outbreak of an infectious disease? - 1. Record
patient's symptoms and find similarities with other patients
2. Isolate the bacteria in a lab
3. Go to affected areas and determine the origin of the disease
4. Identify the disease using DNA sequencing since pathogens alter certain DNA sequences
What is bioinformatics? - The collection, classification, storage, and analysis of biochemical and
biological information using computers. (Especially applied in molecular genetics and genomics)
How can DNA sequences be used to identify disease pathogens? - You can observe mutations and
abnormalities that disease pathogens have
What is an antibody? - A blood protein in the body produced by B-cells (B-Lymphocytes) that fight
against a foreign substance by recognizing a specific part of it.
How do antibodies identify and inactivate antigens? - 1. Shape recognition
2. Proteins of the antigens are configured to specific antibodies, so the foreign antigens bind to the
specific antibodies that inactivate them
How can the ELISA assay be used to detect disease? - 1. Primary antibodies attach to specific antigen
2. Secondary antibody attaches to primary antibody
3. When enzyme substrate is added, color change occurs
Why is it important for doctors to know the concentration of the disease antigen present in a
patient's system? - Higher concentration = closer to patient zero
, Patient Zero - The first person to be infected with a particular disease
What steps do scientists take to diagnose, treat, and prevent future spread of a disease outbreak? -
1. Record the symptoms
2. Locate the origin of the pathogen
3. Run tests to determine antibodies and antigens
4. Take preventative measures (quarantine, wash hands often, etc.)
How were the following used in managing the outbreak on Sue Smith's campus:
PCR, Bioinformatics/BLAST, and ELISA? - These tests determine the concentration of the disease,
which lead to the source of the outbreak
Which part of the bacterial cell allows the bacteria to attach to specific surfaces? - Adhesins, or cell-
surface components/appendages of the bacteria that facilitate attachment to other cells or surfaces
Which bacterial structure is involved with protein synthesis? - rRNA, tRNA, and mRNA (Ribosomal,
Transfer, Messenger)
What is an endotoxin? - A toxin that is inherently present inside a bacterial cell
What is the structural difference between Gram positive and Gram negative bacteria? - Gram
positive:
•Purple
•Thick cell wall
Gram negative:
•Pink
•Thin cell wall
How do antibiotics work to fight bacteria? - •Inhibit the cell wall
•Stop bacteria from reproducing/sharing resistant DNA
Penicillin - An antibiotic that penetrates and destroys the cell wall of gram negative bacteria
