BIOL239 Study Guide - Midterm Guide: Sister Chromatids, Phenotypic Trait, Allosome

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lemondolphin259

22 Aug 2016

School

University of Waterloo

Department

Biology

Course

BIOL239

Professor

Christine Dupont

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Document Summary

Belyaev; scientific american that experimented on fox domestication. Hypotheses before mendel: one parent contributed more than the other in the offspring"s phenotype, and also parental traits become mixed and forever changed in the offspring. Mendel; plant breeder that experimented with garden peas. Easy to cross-fertilize, many offspring, grew quickly. Clear traits, established pure-breeding lines, controlled breeding. Monohybrid crosses: between individuals that differ in only one trait, all f 1 resembles one of the parental strains, 3 to 1 phenotypic ratio in f2 where the lost trait reappears. Alleles: discrete units of inheritance for a gene. Tall or short are alleles for the height gene, s for short recessive allele, and s for tall dominant allele homozygous dominant. *different alleles differ in nucleotide sequence = changes in amino acid sequence/amount of protein. Test crosses: must be a cross against a homozygous recessive phenotype. Yellow or green are alleles for the colour of peas, g for green recessive allele, and.

Related Questions

In need of assistance. Please help answer the following.

1) Pure-breeding yellow guinea pigs crossedwith pure-breeding white guinea pigs produce only cream-coloredoffspring. This pattern indicates incomplete dominance. Rough hairis found to be dominant to smooth hair. Give the F1 and F2genotypic and phenotypic ratios of a cross of a smooth white guineapig with a homozygous rough yellow guinea pig.

2) A breeder of cattle has a herd of white cowsand a roan bull. Hair color in this breed is controlled by anincomplete dominant gene. The two homozygous forms are either redor white, and the heterozygous is roan. Answer the followingquestions please

What color calves are expected and in whatproportion?

Outline a procedure to develop an all-redherd.

3) In horses, black coat color is influenced bythe dominant allele (B), and chestnut coat color is influenced bythe recessive allele (b). Trotting gait is due to a dominant gene(T), pacing gait to the recessive allele (t). If a homozygous blacktrotter is crossed with a chestnut pacer:

What will be the appearance of the F1 and F2generations?

Which phenotype will be the most common?

Which genotype will be the most common?

Which of the potential offspring will be certain tobreed true?

4) In garden peas, one pair of alleles controlsthe height of the plant and a second pair of alleles controlsflower color. The allele for tall (D) is dominant to the allele fordwarf (d), and the allele for purple (P) is dominant for the allelefor white (p). A tall purple crossed with a tall purple produces Â¾tall purple and Â¼ tall white. What is the genotype of the parents?

5) Three alleles control the ABO blood types.I^A and I^B are codominant genes, so thecombination of I^AI^B produces the AB bloodtype. The third allele I^ois recessive to the other twoalleles. Indicate which of these parents could produce the givenchild and submit your response to the instructor.

A X AB produce B child.

A X O produce A child.

A X B produce O child.

A X AB produce O child.

A X AB produce B child.

B X B produce O child.

AB X AB produce A child.

goldspider471

If an organismâs diploid chromosome number is 18, how many different possible combinations of homologous chromosomes lining up during meiosis exist for the eggs or sperm produced by that organism?

	A.	512
	B.	9
	C.	18
	D.	128
	E.	36

At the end of metaphase I, _______________ separate.

	A.	sister chromatids
	B.	germ cells
	C.	homologous chromosomes
	D.	haploid chromatids
	E.	centrioles

Mendel observed that dominant traits

	A.	are seen in all of the F1 hybrid pea plants in his experiments.
	B.	are expressed in all plants.
	C.	were absent in the F1 generation of pea plants that he used in his experiments.
	D.	were the only traits seen in the F2 generation of pea plants in his experiments.
	E.	are only expressed in hybrids.

Cytokinesis in plant cells differs from cytokinesis in animal cells because

	A.	there is no difference.
	B.	in plant cells, the cell plate must also divide into two parts.
	C.	the contractile protein, actin, is important only in plant cells.
	D.	plant cells have a rigid cell wall.
	E.	a contractile ring forms only in plant cells.

Sickle cell anemia is an example of what type of inheritance?

	A.	complete dominance
	B.	incomplete dominance
	C.	codominance
	D.	multiple alleles
	E.	recessive dominance

Which of the following statements is true:

	A.	The dominant allele is masked in homozygous dominant individuals.
	B.	With recessive genetic disorders, if both parents are carriers, the offspring will all be affected.
	C.	In carriers, the recessive allele causes an intermediate phenotype.
	D.	In recessive genetic disorders, the mother and/or father of an affected individual must also be affected.
	E.	With dominant genetic disorders, the mother and/or father of an affected individual must also be affected.

Skin cancers typically develop in the

	A.	upper layers of the epidermis.
	B.	lower layers of the dermis.
	C.	subcutaneous layer.
	D.	lower layers of the epidermis.
	E.	upper layers of the dermis.

Duchenne muscular dystrophy (MD) is inherited from an X-linked recessive allele. What is the probability that a son with Duchenne MD inherited this disease from his biological father?

	A.	1/2
	B.	0
	C.	1/16
	D.	1/4
	E.	1/8

The genetic makeup of a particular trait in an individual is its

	A.	genotype.
	B.	heterozygosity.
	C.	phenotype.
	D.	filial.
	E.	dominance.

What structure holds the sister chromatids to the spindle fibers?

	A.	chromatin
	B.	kinetochore
	C.	MPF
	D.	centromere
	E.	cyclin

If you view a cell in which the genetic material is beginning to be visible as separate bodies, and the nucleus has disappeared from view, you may surmise that the cells is in

	A.	telophase.
	B.	anaphase.
	C.	interphase.
	D.	metaphase.
	E.	prophase.

Gregor Mendel was successful in his analysis of the genetics of pea plants because

	A.	he examined and analyzed both the F1 and F2 generations.
	B.	he studied the parental plants to determine their differences.
	C.	he decided to only look at his results in an objective manner.
	D.	he studied a trait that had a strange inheritance pattern.
	E.	pea plants have genetics different from other organisms.

Tall corn plants (T) are dominant to dwarf plants (tt). Solid green leaves (G) are dominant to leaves with a white tip (gg). A cross between two corn plants yielded the following phenotypes: 51 tall plants with a white tip on their leaves; 43 dwarf plants with solid leaves; 48 dwarf plants with white tips on their leaves; 45 tall plants with solid leaves. What are the genotypes of the parents that produced these plants?

	A.	None of the above
	B.	TtGg x Ttgg
	C.	ttGG x TTgg
	D.	TtGg x TtGg
	E.	TtGg x ttgg

In humans, a gene that has been identified as causing a type of skin cancer is the

	A.	superwoman echidna.
	B.	mutant superman.
	C.	sonic hedgehog.
	D.	mutant mole rat.
	E.	superhero aardvark.

The segregation principle states that in sexually reproducing diploid organisms the two copies of each gene

	A.	segregate from each other during meiosis.
	B.	must always be the same allele.
	C.	separate from each other during mitosis.
	D.	will both wind up in either the sperm or egg.
	E.	move together as a unit during meiosis.

In what phases is the genetic material in the cell correctly referred to as chromatids?

	A.	metaphase and telophase
	B.	anaphase and metaphase
	C.	interphase and telophase
	D.	interphase and prophase
	E.	metaphase and prophase

Consider two traits for an organism, determined by two genes, each of which is governed by at least two alleles. In the case of a dihybrid individual, the gametes formed will be of either the parental type or the recombinant type. Recombinant type gametes are formed because of

	A.	the principle of dihybrids.
	B.	multiple alleles.
	C.	heterozygosity.
	D.	incomplete dominance.
	E.	independent assortment.

An allele is

	A.	an alternate form of a gene.
	B.	always recessive.
	C.	the main factor determining a trait.
	D.	always one of a pair.
	E.	the dominant form of a gene.

After the DNA is replicated, and it condenses in prophase, two identical rods of DNA are seen. These are

	A.	spindle fibers.
	B.	kinetochores.
	C.	chromatids.
	D.	chromatin.
	E.	centromeres.

Special cells found in the gonads that give rise to gametes upon division are called

	A.	egg cells.
	B.	somatic cells.
	C.	germ cells.
	D.	stem cells.
	E.	basal cells.