Lesson 2 Flashcards
Chromosomal speaking, what is the difference between males and females?
Females: 23rd chromosome pair is XX
Males: 23rd chromosome pair is Xy
A reproductive cell that can reproduce a new individual if it combines with a reproductive cell of the opposite sex.
Gamete
A gene that codes with other genes to affect a specific trait. e.g. Height: tall gene + short gene = medium height.
Additive gene
Name 2 common X-linked disorders (recessive X chromosome genes that are more common in men as there isn’t a corresponding X chromosome to potentially counteract the disorder)
Red-green color blindness
Hemophilia
What year did the human genome project map the specific gene sequence of each chromosome?
2001
Approximately how many genes does a human have?
30,000
This genetic disorder results in:
Abnormal digestion of proteins, possible mental retardation or hyperactivity, and is preventable through diet.
Phenylketonuria
PKU
This genetic disorder is due to the absence of an X chromosome on the 23rd pair. Only affects girls and may result in impaired cognitive function, psychosocial development, or sexual development.
Turner syndrome
This genetic disorder is due to an extra chromosome on the 21st pair.
Down Syndrome or trisomy 21
This disease is due to a genetic mutation that results in a central nervous system disorder that stays inactive until adulthood.
Huntington’s Disease
This genetic disorder is a sex-linked disorder that is carried on the X chromosome. Produces mild to moderate cognitive impairment and is the scone leading cause of mental retardation in the United States. Affects boys more than girls.
Fragile X Syndrome
This genetic disorder is inherited through a recessive gene. It is an enzyme disease in which gangliosides, products of fat metabolism, accumulate in tissues. Produces blindness and muscle degeneration.
Tay-Sach’s Disease
This genetic disorder is found in boys and results from the presence of an abnormal sex chromosome on the 23rd pair: XXY. Results in abnormal growth patterns usually evident at puberty, as well as cognitive delays.
Klinefelter’s Syndrome
This genetic disease is a dominant inheritance for early onset, but multi-factorial causation after 60 years. Results in loss of memory with increasing mental impairment.
Alzheimer’s Disease
When the cell forms with 23 chromosomes each from the mother and father, what is it called?
Zygote
What are 3 common pre-natal genetic tests performed on the unborn?
Amniocentesis
Chorionic Villus sampling
Ultrasound Sonography
What are the 3 stages of prenatal growth and development?
Germinal
Embryonic
Fetal
First and shortest prenatal stage lasting from fertilization to two weeks. The fertilized egg is now called a blastocyte and moves from the Fallopian tube to the uterine wall.
Germinal stage (pre-embryonic)
Second stage of the prenatal period lasting from 2 weeks to 8 weeks. Initial development of major organs and basic body structure.
Embryonic stage
3rd stage of prenatal development lasting from about 8-weeks until birth.
Fetal stage
If rubella strikes before ?, it can cause serious effects to the unborn baby?
11 weeks
What is the name of the drug given to women for morning sickness in the 50’s that caused severe birth defects? (Stumps for limbs)
Thalidomide
What is the primary preventable cause of mental retardation in the United States?
Fetal Alcohol Syndrome (FAS)
A factor that can negatively impact prenatal development, can lead to birth defects or even death.
Teratogen
