Forensics SAC 2

Chromosomes are found in the...

nucleus of every cell in the body except red blood cells.

We have ____ chromosomes

46

We get ___ chromosomes from each parent

23

What information is found in chromosomes?

Genetic information

Nucleotides store...

inherited characteristics of organisms and code for proteins.

A single nucleotide contains...

a phosphate group, deoxyribose sugar and a nitrogenous base

The phosphate group is the ____ in all nucleotides

same

the deoxyribose sugar is also known as the _____ sugar

pentose

A phosphate group is in the shape of a...

circle

The deoxyribose sugar is in the shape of a...

pentagon

The nitrogenous base is in the shape of a...

rectangle

what are the 4 types of nitrogenous bases?

Adenine, Thymine, Guanine, Cytosine

What is the structure of DNA?

double stranded

what does double-stranded mean?

2 or more chains or strands twisted into a double helix

Hydrogen bonds exist between...

the base pairs to stabilise the double helix

where do hydrogen bonds occur?

at the nitrogenous base

the 2 strands run...

antiparallel - opposite directions

PCR stands for...

polymerase chain reaction

PCR is used for...

DNA amplification

PCR makes...

identical and multiple copies of DNA

Gel electrophoresis...

separates and visualises nucleotides based on their size

What are the 3 PCR steps?

denaturation, annealing, extension

In denaturation, the sample is ________ .

heated

In denaturation, ____________ break and leave us with a ________ strand of DNA.

hydrogen bonds, single

When annealing, the temperature is _______ to ___-___.

reduced

When annealing, primers...

anneal (bind) to the DNA.

When extending, the temperature is _______ to _____.

increased

...attaches to the primers

taq polymerase

adds free ________ to form ______ _______ _____. (extension)

nucleotides, double stranded DNA

When electric current is applied... (gel electrophoresis)

Negative DNA will move towards the positive electrode.

Small DNA will move ______

faster

Larger DNA will move ______

slower

DNA is ______ charged.

negatively

DNA profiling is a technique used to...

compare and identify individuals based on their unique DNA sequence

DNA profiling is used in forensics to...

identify a perpetrator, deceased person or confirm the biological parents of a child.

DNA profiling can make DNA look like a...

barcode

A DNA profiling barcode can show a ________ pattern.

unique

What makes up our blood? (4 things)

red blood cells, white blood cells, plasma, platelets

red blood cells contain...

a protein called hemoglobin that carries oxygen to our cells

white blood cells are part of the ______ system

immune

white blood cells destroy...

infectious agents called pathogens

pathogens can be...

bacteria and viruses

Plasma is the _______ liquid that contains ______ and _______.

yellowish, nutrients and electrolytes

Plasma also contains _______ that fight against _______

antibodies, infections

platelets is the ______ factors.

clotting

The clotting factor is a process called...

coagulation

The most common way to categorise blood is the _____ system

ABO

Blood groups are not _____ like fingerprints

unique

Differences arise from the...

presence or absence of of different proteins called antigens on the surface of red blood cells.

Not all blood groups are...

compatible with each other

What are the 4 main types of blood?

A,B,AB,o

______ determine the blood type.

antigens

Antibodies...

combine chemically with substances the body doesn't recognise

in short, antibodies...

invade unknown particles

antibodies will recognise if the...

wrong blood type is present

If the wrong blood type is present, antibodies will...

bind to the blood and agglutinate

agglutination occurs when...

blood becomes clumpy and thick.

agglutination is when...

blood does not circulate blood and can cause to death

The Rh factor is also an _______ on the ______ _____ _____.

antigen, red blood cell

Those with the Rh factor are ______

Rh+

Those without the Rh factor are ______

Rh-

People with o blood type are known as...

universal donors

People with o blood type...

can give blood to any blood type.

People with AB blood type are known as...

universal recipents

People with AB blood type...

can receive and blood type

Rh+ can receive...

+ or -

Rh- can receive...

- only

Our basic unit of genetic information is the...

gene

The A blood type has _____ antigens.

A

The B blood type has _____ antigens.

B

The AB blood type has _____ antigens.

A and B

The O blood type has _____ antigens.

none

The A blood type has _____ antibodies.

Anti-B

The B blood type has _____ antibodies

Anti-A

The AB blood type has _____ antibodies.

none

The O blood type has _____ antibodies.

Anti-A and Anti-B

What is genotype?

The genetic information that is inherited.

What is phenotype?

The physical trait shown.

Skeletal remains give clues into...

who a person is and how they died.

Forensic anthropology is a...

subdivision in science that seeks to identify human remains.

when skeletal remains are found...

the bones and surrounding area are treated like a crime scene

First skeletal remains are examined to determine...

if they are human

What are the 4 things you can tell from skeletal remains?

sex

age

height

ethnic region

List 3 differences between a male and a female skull.

A male skull is U-shaped whereas a female mandible is v-shaped.

The eye orbital for a male is more square whereas it is more round for females.

The nuchal crest for males is rough and bumpy whereas a female's nuchal crest is more smooth.

One of the most _______ methods of determining sex of an adult skeleton is to examine the _____ ______

reliable

pelvic bone

Why is the pelvic bone so different between males and females.

Child bearing

Identify 2 differences between the female and male pelvis.

The female pelvis has wider, oval-shaped hips, whereas the male has narrower, heart-shaped hips.

The female has a shorter, outwards coccyx, whereas the male has a longer, inwards coccyx.

Throughout a humans life, bones are...

always produced, repaired and broken down.

After age 30...

bones break down faster than they are built.

After age 30, bone density _______.

weakens

An odontologist can examine dental remains to find out...

their age and dental hygiene

Toxicology is the study of...

Analysing biological samples to find the presence of toxins.

A toxicologist...

determines if chemicals or substances are dangerous to humans.

Why is toxicology important?

When conducting an autopsy, physical wounds may not be present.

What are the 3 types of drugs?

stimulants

depressants

hallucinogens

Stimulants...

increases the activity of an individual's nervous system

Give 2 examples of stimulants.

cocaine

meth

Depressants...

are psychoactive drugs that cause drowsiness.

Give 2 examples of depressants.

sleeping pills

alcohol

Hallucinogens...

Cause alterations in a person's perception of reality.