Principles of Biomedical Science - End of Course Assessment Review

Flashcards for reviewing key concepts for the end-of-course assessment.

Name 5 pieces of evidence that might be obtained at a crime scene.

Hair, fingerprints, blood spatter pattern, saliva, digital evidence, DNA

What does a medical examiner look for when performing an autopsy?

Evidence of how a person died; manner, cause, and mechanism of death. Toxicology, evidence of disease, evidence of injury.

What is the difference between manner of death and cause of death?

Manner of death is the overarching reason (natural vs. unnatural). Cause of death is the specific reason (stroke, gunshot wound). Mechanism is how the body died (exsanguination, asphyxiation).

If a body is found at 8 AM with a rectal temperature of 95.2 F, what is an approximate time of death?

Approximately 6 AM (using the provided calculation).

Draw and label the parts of a nucleotide.

Phosphate group (negative charge), nitrogenous base, and a deoxyribose sugar (for DNA).

Name all four bases of DNA. Which bases are structurally similar to one another?

Adenine (A), Guanine (G), Cytosine (C), and Thymine (T). Adenine and Guanine are purines (double ring). Cytosine and Thymine are pyrimidines (single ring).

What are the base pairs of DNA?

A-T and G-C (Chargaff's rule).

Which base is NOT present in RNA?

Thymine (T), which is replaced with Uracil (U).

What do restriction enzymes do?

Cut or digest a strand of DNA at particular places.

What is the purpose of gel electrophoresis?

Separates DNA molecules for visual analysis.

What way does DNA run on the gel?

From negative end to positive end.

How does DNA differ from person to person?

The sequence of base pairs is different.

Write the strand of DNA that would bind with this strand: GAATACGAT

CTTATGCTA

What is the independent variable?

Drug concentration

What is the dependent variable?

Number of dead cells

What is the control group?

The one with 0% drug added

What is an RFLP? How is it used in DNA analysis?

Restriction Fragment Length Polymorphism. Differences in DNA fragment lengths are visualized via gel electrophoresis to identify suspects or alleles.

What restriction enzymes could be used to determine whether someone has FH?

The cut there would show 2 fragments vs. the one long RFLP When run on a gel.

What does PCR stand for? What is the purpose of PCR?

Polymerase Chain Reaction. To produce millions of copies of a specific DNA sequence from a small amount of DNA.

What are the three types of presumptive tests?

Leukocrystal violet (LCV), Luminol, and Kastle Meyer.

What are the components of blood and their roles?

Platelets (thrombocytes) assist in clotting; Red blood cells (erythrocytes) transport O2/nutrients & remove wastes; White blood cells (leukocytes) are active in immune response; Plasma is the liquid portion; Hemoglobin is a protein in RBCs allowing O2 to bind; Hematocrit is the proportion of RBCs to total blood volume.

What blood type is the universal donor?

O negative

Why are people with Type AB considered the “universal recipient”?

They do not have any antibodies to A or B blood present therefore nothing would attack any of the other blood types.

You complete blood type testing and there is no agglutination with either anti-A or anti-B antibodies. What type of blood is present?

This would be type O because there are no antigens present when treated with the anti A or anti B antibodies to agglutinate

Compare Type 1 and Type 2 diabetes.

Type 1: Body produces little to no insulin because of damaged beta cells. Treated with insulin. Type 2: Cells don't respond to insulin or are damaged. Treated with diet, exercise, medication.

When body temperature rises, you sweat, bringing your body temperature back to normal. Is this negative or positive feedback?

Negative

When you get cut, clotting factors come to the site, which attracts more and more clotting factors. Is this negative or positive feedback?

Positive

When oxygen levels get low in the body, respiration rate increases until oxygen levels return to normal. Is this negative or positive feedback?

Negative

What is osmosis?

Movement of water from high to low concentration

Why are diabetics constantly dehydrated and urinating so often?

Water moves from the cells into the blood because of high glucose. Kidneys process more blood and pull out more water.

List three complications of diabetes.

Nerve damage, kidney damage, and heart disease.

List three lifestyle changes diabetics can make to manage their disease.

No smoking, healthy diet, more exercise.

What is hyperglycemia?

High blood sugar; caused by diabetes

What is hypoglycemia?

Low blood sugar; can be caused by diabetes

What is the diagnostic test used for diabetes?

Hemoglobin A1C is the definitive test that shows average sugar levels over the past 3 months in a patient (and glucose tolerance test can be used as well as insulin level measurements)

Describe the process of protein synthesis.

DNA is transcribed into mRNA in the nucleus. mRNA goes to ribosomes where it is translated into codons, which are amino acids that build proteins. tRNA binds to codons to synthesize the amino acid chain (protein).

Transcribe this DNA sequence into mRNA, then tRNA, and then translate it into an amino acid sequence: TAC GGG AGA CTA ATT

mRNA: AUG CCC UCU GAU UAA tRNA: UAC GGG AGA CUA AUU Amino Acid Sequence: Met/Pro/Ser/Asp/STOP

This process makes new body cells for repair & replacement.

Mitosis

This process makes identical copies of the parent cell.

Mitosis

This process creates sex cells of sperm and egg.

Meiosis

Each body cell has ____ chromosomes. Each gamete has ____ chromosomes.

46, 23

Why does sickle cell disease run in families, yet is not present in every generation?

It is a recessive genetic condition, so not every person gets it but they may be a carrier.

What is Familial Hypercholesterolemia?

A disorder that causes high LDL levels. It is genetic and dominant. The LDLR gene has a point mutation. The protein that clears LDL from the bloodstream is affected.

What is the pathway blood takes as it passes through the heart?

Deoxygenated blood enters the heart in the superior and inferior vena cavae -> right atrium -> tricuspid valve -> right ventricle -> pulmonary artery -> lungs -> oxygenated blood enters through the pulmonary veins -> left atrium -> bicuspid/mitral valve -> left ventricle -> aortic valve -> aorta -> to the body

What is the role of valves in the heart? What is mitral valve prolapse? How can it lead to left ventricular hypertrophy?

Valves prevent backflow. Mitral valve prolapse is when the valve doesn't close all the way causing regurgitation. The left ventricle has to pump harder, which can lead to thickening.

What is heart rate?

How many times heart beats per min

What is a normal heart rate?

60-100 bpm

What is blood pressure?

The force exerted by blood on the walls of the arteries when the heart beats. (mmHg)

How is blood pressure measured?

With a sphygmomanometer and stethoscope (if manual)

What is normal blood pressure?

90-120/60-80 mmHg

What are the units of blood pressure?

mmHg

What medication is used to treat high blood pressure?

Diuretics, beta-blockers, Ca channel blockers (anti-hypertensives)

What does EKG stand for? What does it measure?

Electrocardiogram (also ECG). It measures the electrical conductivity of the heart.

What are two major functions of cholesterol in the body?

Build and maintain cell membranes and to make hormones

What medication is used to treat cholesterol?

Meds like Lipitor

What is atherosclerosis? How can it affect blood pressure?

The buildup of waxy/fatty substances on the walls of blood vessels. It causes constriction of the arteries and therefore higher pressure to push the blood through them due to the slower flow.

Name four risk factors for developing heart disease. Which are modifiable?

Sedentary lifestyle (mod), diabetes (non-mod), obesity (mod), smoking (mod), genetics (non-mod)

What is sickle cell anemia? How does a person acquire it?

SCD(isease) is a hemoglobinopathy, which means a disease of the hemoglobin on the red blood cells. It’s genetic. The red blood cells form a “sickle” shape due to the change in the structure of the Hemoglobin.

What does HIPAA stand for and what does it say?

Health Information Portability and Accountability Act. It allowed for patients to change insurance and keep coverage. Then it changed to covering patient information confidentiality.

What are the three circumstances under which HIPAA can be broken?

Law enforcement needs it; reporting to the health department; in an extreme emergency situation.

List 3 ways to prevent spread of disease.

Wash hands; keep food at good temp; clean surfaces; vaccination; stay home when sick, etc.

List and explain 3 techniques that are used to identify bacteria.

Gram staining, colony morphology (size and shape and color), chemical/metabolic tests

Explain the structural difference between gram-positive and gram-negative bacteria.

Gram pos have a thick peptidoglycan layer which “traps” the crystal violet stain. Gram neg have a thin peptidoglycan layer and do not “hold” the stain, so the counterstain is used.

Which one stains pink?

Gram negative

List the classes of common pathogens and give examples of each, how it is spread, and how it is treated.

Prions (nonliving), Fungi (living), Helminths (living), Bacteria (living), Viruses (non-living), Protists.

How can viral infections be prevented?

Wash hands, stay away from people if sick; vaccinate if available; wear a mask if sick; cover cough/sneezes

How can bacterial infections be prevented?

same as above (viral); disinfect surfaces. Treat with antibiotics

Name three parts of the immune system that make up the first line of defense.

Skin, mucus, hairs/cilia, inflammation

What makes up the 2nd line of defense?

White blood cells, phagocytes

What makes of the 3rd line of defense?

Specific: T and B cells; antibodies.

How does a vaccine work?

Uses either a weakened (attenuated) or dead virus to trigger the body to attack and make antibodies. Hopefully the body will “remember” if it is ever exposed again. Sometimes boosters are needed.