PLTW: Biomedical Science Unit 1 TEST

5 steps to a crime scene investigation/how a crime scene is processed

1. Collect evidence
2. Sketch
3. Interview
4. examine
5. photograph

3 primary fingerprint ridge patterns

arch, whorl, loop

arch

whorl

loop

Independent variable

manipulated by the researcher.

Dependent variable

Measurable effect, outcome, or response in which the research is interested. results vary based on the independent variable.

Control Group/variable

The group in an experiment that serves as a comparison against the experimental group where the independent variable is applied.

Forensic Science

The application of scientific knowledge to questions of civil and criminal law.

Hypothesis

Clear prediction of the anticipated results of an experiment.

Negative Control

Control group where we don't know the outcome.

Positive Control

Group expected to have a positve result, allowing the researcher to show that the experiment set up was capable of producing results.

Types of Blood in ABO system

Type A, Type B, Type AB, Type O

Clumping with a serum that is Anti-A indicates
(same with Anti-B)

that the blood type has "B" in it

cuticle

What is the outermost layer of the hair?

cortex

Home to pigment containing granules - gives hair color.

medula

the base of the brainstem; controls heartbeat and breathing

Adenine

A component of the nucleic acids, energy-carrying molecules such as ATP, and certain conenzymes. Chemically, it is a purine base.

Chromosome

Any of the usually linear bodies in the cell nucleus that contain the genetic material.

Cytosine

A component of nucleic acids that carry hereditary information in DNA and RNA in cells. Chemically, it is a pyrimidine base.

Deoxyribonucleic Acid (DNA)

A double-stranded, helical nucleic acid molecule capable of replicating and determining the inherited structure of a cell's proteins.

Gel Electrophoresis

The separation of nucleic acids or proteins, on the basis of their size and electrical charge, by measuring their rate of movement through an electical field in a gel.

Gene

A discrete unit of hereditary information consisting of a specific nucleotide sequence in DNA (or RNA, in some viruses).

Guanine

A component of nucleic acids that carry hereditary information in DNA and RNA in cells. Chemically, it is a purine base.

Double helix

DNA's form

Nucleotide

A building block of DNA, consisting of a five-carbon sugar covalently bonded to a nitrogenous base and a phosphate group.

How is alcohol used to extract DNA?

DNA is insoluble in alcohol, so it forces DNA out

Restriction Enzyme/restriction endonucleases

an enzyme that recognizes specific nucleotide sequences and cuts up DNA.

Restriction Fragment Length Polymorphisms (RFLPs)

A section of DNA that is cut into different pieces by the same restriction enzyme due to differences in the nucleotide sequence (the different sections in a DNA strand vut by restriction enzymes)

Thymine

A component of nucleic acids that carry hereditary information in DNA and RNA in cells. Chemically, it is a pyrimidine base.

What medical profession performs autopsies?

forensic pathologist (medical examiner)

What are the base pairs?

A - T, G - C

What is the difference between the purines and the pryimidines?

Purines have two carbon-nitrogen rings and four nitrogen atoms. Pryimidines have one carbon-nitrogen ring and two nitrogen atoms.

What two base pairs are purines?

Adenine and guanine

What two base pairs are pyrimidines?

Cytosine and guanine

Why do purines bond with pryimidines in the DNA ladder?

They are opposite poles and have the same number of hydrogen bonds.

Explain the role that restriction enzymes and gel electrophoresis play in DNA profiling.

Restriction enzymes cut the DNA at specific nucleotide sequences and gel electrophoresis seperates nucleic acids or proteins by size.

What would happen if the gel was placed with the DNA starting closest to the positive electrode? Explain.

The process wouldn't work because the DNA would run backwards.

True/False: Chromosomes are composed of genes and chromosomes make up DNA.

True

If someobody has blood type A what anti-bodies would they have?

Anti-A antibodies

why do people have different blood types?

Your DNA codes for certain antigens on your red blood cells; those antigens determine your blood type.

Which blood type would give no response to both A and B anti-bodies?

O

What is the relatioship between antibodies and antigens?

Antibodies are proteins that attach to foreign antigens and cause agglutination.

presumptive test

test that presumes the presence of the questioned substanced, looks for hemoglobin protein which contains iron

confirmatory test

test that confirms the presence of blood, looks for certain antigens

how many antigens are in type AB blood?

2

what does a CSI NOT do at a crime scene?ta

pronounce the victim dead at the scene

a microsopic sample of hair can provide us with sex, race, and age but not

identity

if a substance is blood it will have ___ results for each test:

positive - luminol
pink - presumptive
ALWAYS crystals - confirmatory

if a substance is not blood it will have ___ results for each test:

negative: luminol
clear: presumptive
no crystals: confirmatory

the faster the blood droplet falllingthrough air, the (more or less) circular the blood drop will be?

less

as height increases, the diameter of the blood _____

increases

what makes you different in DNA than your friends?

different sequence of nitrogenous bases

our genome is composed of ___

chromosomes

chromosomes are made up of

genes

what does detergent do to help extract DNA?

detergent breaks down the lipids in nuclear/cell membrane which llows DAN to be extracted

if adenine has 30% and cytosine has 20%, what % does guanine have?

20%

is thymine has 15%, what % does adenine have?

30%

if guanine has 40%, what % does thymine have?

10%

what is DNA?

deoxyribonucleic acid, nucleic acid

what is DNA's monomer?

nucleotide

what does meat tenderizer do as a buffer

breaks down the proteins in the bilayer

what arethe parts of DNA?

phosphate group, deoxyribose sugar, and nitrogenous bases

what is the 2nd strand of TTGCACGG?

AACGTGCC

DNA can be found in

blood, semen, urine, sweat, bone, hair, saliva, and clothing

pyrimidine base

thymine and cytosine

purine base

Adenine and Guanine

what does a 911 disbatcher do

recieves the emergency calls

what does a CSI do?

observe, take photos, # the evidence, estimate time of death

what do police do at a crime scene?

arrests the perpetrator if the scenen is "hot", pronounce the scene safe, calls, ambulance, secures the scene

what do EMTs do at aa crime scene?

give immediate medical care, prounounce people dead

what do prosecutors do at a crime scene?

present evidence to the judge to try to prove someone as guilty or innocent

how do mistakes in a criminal investigationcompromise the case?

mistakes can build up on top of each other sending detectives down the wrong paths, etc.

7 steps to experimental design

1. Identify the problem or question
2. Predict a solution to the problem or an answer to the question
3. Design an experiment to test your hypothesis
4. Carry out the experiment
5. Analyze the data and observations
6. State the conclusion
7. Complete a summary paragraph

subjective data

things a person tells you, beliefs, cannot be proven

objective data

information perceptible to the senses; can be proved

vital signs

heart rate/pulse, respiratory rate, etc.

trace evidence

hairs, fibers, glass, small things/evidences that help us figure out where people were

pulse and respiration rate are connected because,

the more your blood pumps, the more oxygen needed for your blood

polygraph tests

record vitals to check when you might be lying vs telling the truth

digital forensic scientist

they track where poeple have gone and what people have posted online, tracking their digital footprint

minutiae

tiny details in a fingerprint, lines, shapes, size, etc.

red blood cells (erythrocytes)

carry oxygen from lungs to body cells, bring up carbon dioxide to be exhaled

white blood cells (leukocytes)

defend our body from disease by fighting the diease and creating antibodies against diseases

Platelets (thrombocytes)

create blood clotting

antigens

Foreign material that invades the body/disease

antibodies

Specialized proteins that aid in destroying infectious agents

aggulation

clumping of red blood cells, like when testing for blood type

blood spatter

Can be analyzed to determine patterns that give investigators clues to how a crime might have happened

blood transfers

when blood is transfered onto other objects

0 blood type

universal donor, no aggulation

AB blood type

universal recipient, A & B aggulation

A blood type

A aggulation

B blood type

B aggulation

hemoglobin

Oxygen carrying pigment in red blood cells

blood spatter analyst

Career responsible for reconstructing a scene based on blood evidence, trying to figure out what happened in the crime due to the certain blood spatter (direction, force, etc)

genome

all of an organism's genetic material

protein

chromosome codes for proteins which codes for a trait

eukaryotes

has nucleus, DNA in nucleus

prokaryotes

no nucleus, DNA in cytoplasm