Cell Division
Two diploid cells are created during_______
mitosis
Telophase
If the dominant phenotype is black fur (B) and the recessive phenotype is brown fur (b).
If a heterozygous animal was crossed with a homozygous dominant animal. Would any of the resulting offspring show the recessive phenotype?
NO.
heterozyous Bb crossed with homozygous dominant BB would always result with a B allele in each of the offspring. There is not second b allele for offspring to inherit so there can be no bb and thus no brown fur result.
Where on the DNA does replication begin?
The ori site or origin of replication. A prokaryotic cell such as E. coli would only have 1 ori site on the circular genome. But a eukaryote like a frog would have multiple ori sites on each of its linear DNA strands.
Where do transcription and translation occur in a prokaryotic cell such as E. coli?
Where does transcription and translation occur in a eukaryotic cell such as algae?
Both occur in the cytoplasm of prokaryotes
Transcription occurs in the nucleus. Translation occurs in the cytoplasm
External controls such as available nutrients control this type of cell division in prokaryotic cells
binary fission
Homologous chromosomes replicate during _________ at the start of Meiosis.
Interphase- S
There are 3 alleles for feather color in parrots: IB , IG, and i. The I allele produces blue feathers, the I allele produces green feather, and the i allele will produce pink feathers. If a bird inherited both the IB and IG allele it would have both blue and green feathers. This is an example of __________
codominance
What enzyme lays down the RNA primer by the ori site?
Primase
What is the central dogma?
DNA transcribes to form mRNA (messenger RNA) which then is translated to form a protein (amino acid sequence)
If the volume of DNA inside a cell after S of Interphase is represented as 10x. Then what was the volume of DNA in that same cell during G1 of Interphase?
5x during G1....DNA is doubled during S of Interphase with DNA replication
If the diploid parent cell has 14 chromosomes (2n=14). Then how many chromosomes will the egg cell have?
Eggs are gametes. Gametes have the haploid # of chromosomes and thus half of 14 is 7.
If a homozygous or true breeding blue newt is mated with a homozygous or true breeding red newt. The resulting offspring are all purple. Not blue and not red. What genetic situation is this an example of?
Incomplete dominance. Two individual homozygous for a trait (blue skin or red skin) when crossed produce all heterozygote offspring. IF this had been a case of complete dominance then all of the offspring would have been either blue or red. BUT they are not! They are a blend of the 2 colors with a new phenotype which is purple.
What enzyme links together the Okazaki fragments of the lagging replication fork?
DNA ligase
What initiates (aka begins or starts) translation and what ends or completes translation?
A Start codon on the mRNA begins translation (only 1 AUG which carries the amino acid Met). A Stop codon on the mRNA end translation. There are 3 different stop codons and none of them have amino acids attached to them.
If a gamete such as a sperm cell, has 22 chromosomes. How many chromosomes do the somatic cells of the this same organism have?
gametes have the haploid number of chromsomes, so half the normal #. In order to find the somatic cell # which is the diploid # you simply multiply by 2. So 22 x 2= 44
When tetrads of homologous chromosomes line up along the equatorial plate. What phase is this? and What occurs during this time to contribute to the genetic variation?
Meiosis I during Metaphase I and Independent Assortment occurs
Hemophilia is a recessive sex-linked gene on the X chromosome. Eugene has hemophilia he marries Laura who is a carrier for hemophilia. Perform the cross. What is the probability that they will have a child with hemophilia?
50% chance of a child with hemophilia
Eugene's genotype: XhY
Laura's genotype: XhX
What enzyme grows the replicating DNA strand by adding nucelotides to the 3' end?
What else does this same enzyme do?
DNA polymerase
It also proofreads the DNA for mistakes
What initiates (aka begins or starts) transcription and what ends or completes transcription?
A promoter on the DNA begins transcription and a terminator on the DNA is what tells the cell that transcription is complete.
Provide 3 reasons why a cell would divide?
1. For reproduction (either asexually or sexually)
2. Growth
3. Repair, replacement/regeneration of cells or parts
When do haploid cells that contain sister chromatids divide?
Meiosis II- the second division is the separation of the chromatids. They will divide and form 4 haploid cells.
Teresa has type A blood. Her father and mother both have type AB blood. Teresa has children with Danny. Danny has type B blood. His father had type O blood and his mother had type AB blood. What are the genotypes of both Teresa and Danny? What are the possible blood types their children could have?
Teresa: IAIA Danny:IBi
Their children: IAIB type AB blood or type A blood IAi
Part 1: What enzyme replaces the RNA primer with DNA language at the end of replication?
Part 2: How many RNA primers does this same enzyme replace on a lagging strand?
DNA polymerase I
It replaces multiple RNA primers with DNA language on the lagging strand. Only needs to replace 1 RNA primer on the leading strand because its continuous (no fragments)
Correctly translate the following mRNA strand. Use the codon chart on page 298 of your textbook.
3' A U G A A U U G A U U U U G G G U A G C 5'
Read mRNA in the 5' to 3' direction for translation.
Methionine-Glycine-Phenylalanine-Serine