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Questions and Answers
Which type of medicine can stop antibodies from reacting to a baby's Rh positive cells?
Which type of medicine can stop antibodies from reacting to a baby's Rh positive cells?
Genes responsible for ABO blood types change due to environmental influences.
Genes responsible for ABO blood types change due to environmental influences.
False
How are ABO blood types inherited?
How are ABO blood types inherited?
1 of 3 alleles (A, B, or O) from each parent
The Kastle-Meyer test uses drops of ethanol and phenolphthalein indicator to detect the presence of ________ in blood.
The Kastle-Meyer test uses drops of ethanol and phenolphthalein indicator to detect the presence of ________ in blood.
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Match the presumptive blood test with its method of detection:
Match the presumptive blood test with its method of detection:
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What are some examples of bodily fluids?
What are some examples of bodily fluids?
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What are the two categories that bodily fluids can be classified into?
What are the two categories that bodily fluids can be classified into?
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DNA typing is based on the fact that every individual except identical twins has the same DNA.
DNA typing is based on the fact that every individual except identical twins has the same DNA.
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What is the liquid part of blood that makes up about 60% of blood's volume? Plasma is mainly made of __________.
What is the liquid part of blood that makes up about 60% of blood's volume? Plasma is mainly made of __________.
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Match the blood type with the compatible plasma type:
Match the blood type with the compatible plasma type:
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Study Notes
Body Fluids
- Definition: Body fluids are liquids originating from inside the bodies of living humans, including fluids secreted or excreted from the body.
- Examples: Bile, blood serum, breast milk, gastric juice, mucus, saliva, sebum, semen, sweat, tears, vomit, and urine.
Types of Bodily Fluids
- Secreted fluids: Produced by cells, glands, or organs, including hormones, stomach acid, and bile.
- Excreted fluids: Produced to remove waste from the body, including fecal matter, urine, tears, and sweat.
Bodily Fluids as Evidence
- Body fluids can be found at crime scenes, including blood, semen, and saliva.
- These fluids are considered biological evidence and can be used for identification and characterization through DNA analysis.
Blood
- Definition: Blood is a red fluid that circulates in blood vessels, including veins and arteries.
- Function: Blood acts as the body's transport system and plays a major role in defense against infection.
- Composition: Blood consists of cells (red blood cells, white blood cells, and platelets) and plasma (liquid part of blood).
Blood Groups
- ABO Blood Types:
- A (A antigen, anti-B antibody)
- B (B antigen, anti-A antibody)
- AB (A and B antigens, no antibody)
- O (no antigen, anti-A and anti-B antibodies)
- Rh Factor:
- Rh positive (has D antigen on red blood cells)
- Rh negative (does not have D antigen on red blood cells)
Plasma Compatibility
- Plasma contains anti-A and anti-B antibodies, depending on blood group.
- Plasma compatibility is important for transfusions to avoid antibody reactions.
Inheritance of ABO Blood Types
- Genes on chromosome 9 determine ABO blood types.
- Three alleles (A, B, and O) are inherited from each parent.
- Possible genotypes and phenotypes are determined by the combination of alleles.
Presumptive Tests for Blood
- Luminol test: detects haemoglobin in blood, causing chemiluminescence.
- Kastle-Meyer test: detects peroxidase enzyme in blood.
- Leucomalachite Green test: detects haemoglobin in blood.
- Hemastix: detects blood, producing a green color.
Confirmation of Human Blood
- Precipitin test: detects proteins specific to human blood.
- Anti-human serum is used to identify human blood.
Saliva
- Definition: Saliva is a clear liquid produced in the mouth for lubrication and digestion.
- Composition: Water, enzymes, electrolytes, mucus, and epithelial cells.
- Significance: Saliva can be used for DNA profiling and detecting drugs and toxins.
Semen
- Definition: Semen is the fluid expelled during male ejaculation, carrying sperm cells.
- Significance: Semen is important for DNA profiling and linking suspects to crime scenes.
- Detection: Acid phosphatase test is used to detect semen, and ultraviolet light can visualize latent evidence.### Biological Evidence
- Acid phosphatase is present in semen, but also in other bodily fluids, making it a presumptive test for semen.
- Prostate-Specific Antigen (PSA or P30) is a glycoprotein produced in the prostate gland, useful in detecting semen, but also found in urine, making it a presumptive test.
Microscopic Detection
- Microscopic detection of sperm is a more confirmatory method, allowing for the viewing of sperm cells and proving their presence.
- Fresh and well-preserved samples are preferred, as older samples may have undergone decomposition.
Blood Evidence
- Blood evidence is valuable in crimes such as murder, rape, and assault.
- Blood evidence can aid in investigations by locating the crime scene, identifying the weapon used, and eliminating suspects.
- DNA profiling can be performed on any biological substance.
Analysis and Identification
- Analysis is necessary to determine if a stain is blood, as its appearance varies greatly depending on age, weather, and other factors.
- Species origin must be determined, usually to distinguish between human and non-human blood.
- Further classification involves isoenzyme and DNA analysis.
- DNA typing can determine the sex of the person from whom the sample originated.
Private Laboratories and DNA Analysis
- Private laboratories are used for DNA analysis in cases requiring paternity determination.
- DNA analysis is limited to three or four samples per case: victim's blood, suspect's blood, and one or two questioned samples.
Other Body Fluids
- Seminal stains can be identified by testing for prostatic acid phosphatase, spermatozoa, or P-30 protein, and further identified by DNA typing.
- Saliva stains can be identified by the presence of amylase and further identified by DNA typing.
- Urine can be identified by the presence of creatinine and urea, but cannot be typed.
- Skin tissue can be DNA typed.
Careers and Education
- Forensic biologists, biochemists, and technicians work in laboratories and police forces to analyze biological evidence.
- Some institutions have forensic serologists who specialize in the study of body fluids.
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Description
This quiz covers the different types of bodily fluids, including blood, saliva, and more. Learn about the various fluids produced by the human body and their functions.
