Bio Med TEST nature of science

Nature of science

Changes with evidence, based on observations, testable.

Independent / dependent

Independent = what you change. Dependent = what you measure. Controlled = what stays the same.

Soap test

I: type of detergent. D: stain removal.

Cricket Chirping. Temp change affect on cricket

I: temperature. D: chirps.

Blood splatter experiment.

height dropped from. D: drop size.

Controlled

Blood type, angle, surface, squeeze amount.

5 manners

Homicide (shooting), Suicide (self-inflicted), Natural (disease), Accidental (mushroom poisoning), Undetermined (not enough evidence).

Elderly woman pushed and robbed, dies of a heart attack later

Homicide, because the attack triggered the death. ⚠ You wrote Natural, so check your notes.

Man found in a running car in his garage?

Undetermined. It could be suicide or an accident.

Man dies after eating forest mushrooms

Accidental

Sketch key components?

Scale, key/legend (also title, north arrow, measurements, date/time, evidence locations).

6 search patterns?

Link, Line, Grid, Zone, Spiral, Ray/Wheel.

Spiral, grid, line, zone, ray, link,

Spiral: open outdoor area, one searcher
- Grid: large area, searched twice at right angles
- Line: wide open field, searchers side by side
- Zone: rooms or buildings split into sections
- Ray/Wheel: circular area, from the center out

4 polygraph responses?

Heart rate, sweating, blood pressure, respiration rate.

Why aren't lie detectors used in court

They measure body responses, not lies, so they're unreliable.

PPE

Personal Protective Equipment: gloves, goggles, coat.

Most important PPE for an airborne agent?

Mask

Tests on a suspected blood stain

Presumptive first. If it comes back positive, run a confirmatory test.

Carries oxygen and carbon dioxide

Red blood cells

Defends against bacteria and viruses?

White blood cells

Clear liquid, mostly water?

Plasma

Contains hemoglobin?

Red blood cells.

Responsible for clotting

Platelets

The 8 blood types

A+, A-, B+, B-, AB+, AB-, O+, O-.

Antigens vs antibodies

Antigens = protein flags on cells. Antibodies = fight non-matching antigens.

Agglutination

Blood clumping

How to read a blood type test?

Clumping = antigen present. Control stays smooth.

Universal donor / receiver?

O- (no antigens). AB+ (no antibodies).

Hair parts

Cuticle (outer), cortex (color), medulla (center).

Latent vs patent?

Latent = invisible. Patent = visible.

3 pattern types?

Arch, Loop, Whorl.

Digital evidence?

Texts, calls, photos, videos, social media. Time stamps, can't be erased.