Test 4 Flashcards
Phenotype is exclusively the result of genetic influences
False
The color of your eyes is a normal polygenic trait
True
What is all of the DNA in a set of 23 chromosomes referred to as?
Genome
Use the figure to match the following with a LETTER: This gland stores hormones produced by the hypothalamus.
D- Posterior Pituitary
Use the figure to match the following with a LETTER: This gland produces melatonin.
C- Pineal gland
Which of these is NOT found in the karyotype of a normal human male?
- 46 chromatids
- 46 chromosomes
- 92 DNA molecules
- X and Y chromosomes
- 23 pairs of homologous chromosomes
46 chromatids
If one allele is not phenotypically expressed in the presence of another allele, we say that it is a(an) ______ allele.
recessive
Eye color is caused by genes at multiple loci. This phenomenon is called _____.
Polygenic inheritance
Germ cells have ______ unpaired chromosomes and are thus called _____ cells.
23; haploid (n)
The allele for the cleft chin (C) is dominant to the allele for uncleft chin (c). A male and female who are both heterozygous for cleft chin have a child. What is the chance that this child will have an uncleft chin?
25%
Use the figure to match the following with a LETTER: This gland produces glucocorticoids and mineralocorticoids.
K- Adrenal cortex
The alleles posessed by all members of a population collectively are called the____.
gene pool
All of the body’s nonreproductive cells, called _____, usually have 23 pairs of chromosomes and are thus called _____ cells.
somatic cells; diploid (2n)
Males carry a pair of ______ sex chromosomes
XY
Females carry a pair of _____ sex chromosomes
XX
Use the figure to match the following with a LETTER: This gland produces insulin and glucagon
G- Pancreas
Critical thinking Question:
Which blood type would NOT be possible for children of a type AB mother and a type A father?
O
When one gene produces multiple phenotypic effects, this is called ______.
Pleiotropy
Himalayan rabbits cxarry the C gene, which is required for the development of pigments in the fur, skin and eyes, and whose expression is regulated by the temerature. Specifically, the Cgene is inactive above 35 degrees Celcius, and is maximally active from 15 degrees to 25 degrees celcius. This temperature regulation of gene expression produces rabbits with a distinctive coat coloring. In the warm, central parts of the rabbit’s body, the gene is inactive, and no pigments are produced, causing the fur color to be white. Meanwhile, in the rabbit’s extremities (ears, tip of the nose, and feet), where the temerature is much lower than 35 degrees, the C gene actively produces pigment, making these parts of the animal black.
This is an example of _______.
enviromental influence of genes
Addition of methyl groups to DNA is an example of ______.
epigenetics
Cancers in epiuthelial tissue are called ____
carcinoma
Cancers in bone, other connective tissue, or muscle are called _____
Sarcoma
Mutated Tumor Suppressor genes result in inhibiting development of cancer.
False
Enviromental agents that can cause cancers are called ______
carcinogens
The gestation period is approximately:
280 days
The organ systems rudimentarily (initially) form durning the:
embryonic period
Which of the following inplants in, or attaches to, the endometrium of the uterus?
blastocyst
Where does fertilization usually occur?
ampulla of the uterine tube
What follows immediately after fertilization occurs?
cleavage
How is polyspermy prevented?
cortical reaction