Bio 2 Ch. 19 & 21
Study Guide Q - How many genes are in the human genome?
22,000 - 25,000 genes
Ch. 21 - According to your book wen does aging begin?
40 years old
Ch. 19 - Cystic fibrosis is a genetic disorder that results from the inheritance of 2 recessive alleles. What is the chance that a child will inherit the disorder if one parent is heterozygous for this gene and one parent has cystic fibrosis?
50%
Ch. 19 - There is a male dog has black fur represented as [B], and is homozygous dominant. There is also a female dog with white fur represented as [b], and is heterozygous. What are the genotypes of the offspring?
50% BB and 50% Bb
Study Guide Q - A couple gives birth to 4 girls in a row. What are the chances that the next born will be a boy?
50% girl and 50% boy
Study Guide Q - Approximately what is the human life span in America today?
77 years old
Ch. 19 - There is a male dog has black fur represented as [B], and is homozygous dominant. There is also a female dog with white fur represented as [b], and is heterozygous. What are the phenotypes of the offspring?
All black
Study Guide Q - Embryonic membranes and what they do
Amnion: filled with amniotic fluid & absorbs physical shocks & keeps baby from drying out Allantois: helps form umbilical chord & blood vessels that connect baby to placenta Yolk Sac: hangs from baby's belly & produces blood cells, source of cells that will become sex cells Chorion: outermost layer that produces HCG, which shows up on a pregnancy test
Study Guide Q - Relations ship between chromosomes, alleles, genes, and traits
Chromosome: genetic info in nucleus Allele: alternative version or form of a gene A gene: serves instructions for making different proteins A trait: genes code for proteins that are expressed as traits
Study Guide Q - What's the difference between a dominant and a recessive allele?
Dominant alleles determine appearance and recessive alleles usually have no effect on appearance
Study Guide Q - Developmental stages
Embryo: conception - 2 months Fetus: 2 months - birth Neonate: first month outside of mom Child: 16 months - 12 years Adult: Beyond 20 years old
Study Guide Q - What are the 3 germ layers from the inside out
Endoderm (inside), Mesoderm (middle), and Ectoderm (outside)
Study Guide Q - What are the female and male sex chromosome combinations (genotypes)
Female: "XX" is the fairer sex Male: "XY" makes a guy
Study Guide Q - What is colostrum and what is it "rich" in?
First form of milk produced by the mammary glands, and its rich in antibodies, also known as passive immunity
Study Guide Q - Where does fertilization take place?
In the ovary
Ch. 21 - This hormone is responsible for both milk let down as well and the uterine contractions during delivery.
Oxytocin
Ch. 21 - This hormone is responsible for milk production in the mammary glands.
Prolactin
Study Guide Q - What are telomeres?
Short terminal segments or tips of chromosomes that are removed each time a cell is replicated
Study Guide Q - What is milk composed of?
Sugars, fats, proteins, and water
Ch. 19 - People with Down syndrome have a genotypic condition identified as what?
Trisomy 21
Study Guide Q - What is codominant and know why A and B blood types are codominant.
When both alleles are expressed equally. Blood type O is recessive and blood types A&B are codominant cuz they're expressed equally
Study Guide Q - Definition of incomplete dominance and an example
When the heterozygous genotype results in a phenotype that is intermediate between the 2 homozygous phenotypes of the parents. Ex: Wavy hair
Study Guide Q - Basics of Turner Syndrome
XO (only occurs in women)
Ch. 19 - Which of the following genotypes results in the female gender?
XX
Study Guide Q - Basics of Klinefelter Syndrome
XXY (only occurs in males)
Study Guide Q - What is a zygote and how many chromosomes does a human zygote contain?
Zygote = fusion of sperm and egg, and it has 46 chromosomes
Ch. 21 - Beginning at 2 months up until birth you are considered what?
a fetus
Study Guide Q - What is a karyotype?
a numbered arrangement of all 23 pairs of human chromosomes
Study Guide Q - Identical twins
a zygote splits in half and both zygotes go into the uterus separately with their own placenta. They're genetically identical to one another
Ch. 21 - Which of the following embryonic membranes is a temporary membrane that helps form the blood vessels of the umbilical cord?
allantois
Ch. 21 - From essentially conception to two development in utero you are considered ________.
an embryo
Ch. 19 - Imagine this hypothetical situation. A pure black colored dog is crossed with a pure white colored dog and all the puppies come out black. This would be an example of which of the following situations?
classic dominant and recessive interactions
Ch. 19 - Imagine this hypothetical situation. A pure black colored dog is crossed with a pure white colored dog and all the puppies come out with black and white stripes like a zebra. This would be an example of what situation?
codominance
Ch. 21 - During the first day or so after birth, the breasts produce a water milk which is rich in antibodies. This first milk is called what?
colostrum
Ch. 21 - The placenta forms from embryonic tissue and what?
endometrium
Ch. 19 - If both alleles of a particular gene are identical such as (AA or aa); the person is said to be what?
homozygous
Ch. 19 - An example of a genotype would be what?
homozygous dominant
Ch. 21 - This hormone is a signal that a women is pregnant.
human chorionic gonadotropin (hCG)
Ch. 21 - The structures zona pellucida and corona radiata can be associated with the what?
human egg
Ch. 21 - Research on the aging process shows that wounds of the elderly heal more slowly and that they are more susceptible to disease. These are problems associated with an aging _______ system.
immune
Ch. 19 - Imagine this hypothetical situation A pure black colored dog is crossed with a pure white colored dog and all the puppies come out grey. This would be an example of what situation?
incomplete dominance
Study Guide Q - What is polygenic inheritance and an example
inheritance of phenotypic traits that depend on many genes. Ex: Eye color & height
Ch. 19 - Which one of the following is true regarding an individual who has inherited one sickle cell gene and one normal gene for hemoglobin?
is less likely to contracting malaria
Ch. 21 - Which of the following organs is NOT fully developed in a fetus and is therefore bypassed by the ductus arterisus?
lungs
Ch. 21 - What part of the sperm contains the most mitochondria for generating ATP?
midpiece (B on model shown)
Ch. 21 - The first 3 days or so of human embryonic development occur in the what?
oviduct
Ch. 19 - The Punnett square is a useful tool for what?
predicting the potential genotypes of offspring based on the known genotypes of the parents
Ch. 21 - Maturation of the reproductive organs and the reproductive response is called what?
puberty
Ch. 21 - To penetrate the zona pellucida of the egg cell the sperm?
releases digestive enzymes from the acrosomal cap
Study Guide Q - What are genotypes?
set of alleles that an individual possesses
Ch. 21 - Which of the following is NOT true regarding telomeres and telomerase?
the number of telomeres increases with every cell division
Study Guide Q - What are phenotypes?
the traits that an individual exhibits
Ch. 19 - Assume tall [T] is dominant to dwarf [t]. If a homozygous dominant individual is crossed with a homozygous dwarf, the offspring will be what?
they'll all be tall
Ch. 19 - What is the significance of crossing-over during prophase 1 of meiosis?
to increase the genetic variation of gametes and offspring
Study Guide Q - Basics of Down Syndrome
trisomy 21 (trisomy of chromosome set 21, 3 chromosomes instead of 2)
Study Guide Q - Fraternal twins
when 2 eggs are ovulated and fertilized by 2 different sperm
Ch. 21 - When does a zygote form?
when the nucleus from the sperm fuses with the egg nucleus