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L. monocytogenes

1.) Discuss how L. monocytogenes causes foodborne disease and why it's a significant pathogen.

Hypothesis for single start codon and triple stop codon

I need help with this question. I just need some steps in figuring it out Im totally lost Recall that mRNA has one start codon and three codons. based on what you know about process of gene expression, hypothesize why it would be benefecial to have only one start codon but three stop codons in this process.


Given the assigned sequence of RNA, write down its three reading frames and identify the open reading frame (ORF) A U G G G A U U A U C C A U A C G G C C A C C U U G A Please see the attached file. Please give clear complete explanations!

Genetic map of 3 linked genes found on the same chromosome

In corn, the following recessive genes have been identified on chromosome 3: yg = yellow green seedlings wx = waxy endosperm bz = bronze color From a three point testcross between plants heterozygous for all three genes and plants homozygous recessive for all three genes, the following data

Examining DNA plasmid restriction digest

Hi again. I am attaching a document that provides details on a lab to be done dealing with DNA sequencing. I am looking for assistance in two areas of this lab: 1) p. 67 - questions 1, 2 and 3 These questions ask: 1. how do you predict the DNA bands produced after digesting a recombinant plasmid. How do you know what size

Clarify nature-nurture.

In life span development one of the major develpment issues is nature-nurture. What is this issue and why is it important to the study of human life span development?

Question on isolating mechanisms

______ would prevent interbreeding between two species of fish living in the same habitat. a. sympatric isolating mechanisms b. equilibrium isolating mechanisms c. reproductive isolating mechanisms d. allopatric isolating mechanisms e. preadaptive isolating mechanisms


The migration of breeding individuals between populations causes a corresponding movement of alleles, which is referred to as: a. genetic drift b. directional selection c. natural selection d. gene flow e. mutation

What can cause a change in allele frequency

I need to understand the answer to the following multiple choice question. Which of the following causes changes in allele frequencies? a. genetic drift b. mutation c. natural selection d. gene flow from migration e. all of these

Conditions needed to meet hardy-weinberg predictions

In order to meet the conditions of the Hardy-Weinberg predictions, a population must: a. mutate very quickly b. have a high rate of natural selection c. have a large number of immigrants d. have extensive mating rituals e. be very large

Hardy Weinberg principle.

The Hardy Weinberg principle of genetic equilibrium tells us what to expect when a sexually reproducing population is: a. at genetic equilibirium b. growing c. migrating d. evolving e. mutatiing

Hardy Weinberg principle

The Hardy-Weinberg principle is useful because: a. it explains the existence of variation in populations b. it proves that Mendel was correct for populations c. it describes most populations d. it explains the existence of a large number of species e. it identifies those factors that can change allele or genotype fre

This is a genetics problem dealing with humans with colorblindness and freckles

In human beings, the gene for red green colorblindness (r) is sex linked and recessive to its allele for normal vision (R), while the gene for freckles (F) is autosomal and dominant over its allele for nonfreckled (f). A nonfreckled, normal visioned woman whose father was freckled and colorblind, marries a freckled, colorblind

Nature versus nurture debate

There is a controversy about whether genetics or environment is more important in the development of our personalities. How does genetics impact behavior?

Genetics: gene therapy

Gene therapy is: a. replacing all mutant alleles in body cells b. replacing poor copies of alleles with normal alleles c. replacing a mutant allele in certain body cells with a normal allele d. repairing mutant alleles in certain body cells e. improving gene expression in key body cells

Question on Tay-Sachs

Tay-Sachs disease is a(n)_______ disease that results in blindness, mental retardation, and death due to ________. a. sex-linked; the absence of one of the sex chromosomes b. autosomal recessive; accumulation of lipids in brain cells c. X-linked; accumulation of lipase in cells of sweat glands d. autosomal; the inabili

Monohybrid genetic cross to determine dominant trait

This is the genetic problem that I need to understand how to complete. Sand lizards in white sands new mexico: If for each species a lizard that was homozygous for the dark Mc1r allele had been crossed with a lizard that was homozygous for the light Mc1r allele the resulting F1 generation would have obtained the percentag

organizing effects or the activating effects of hormones

Can you help me with the following: Try this exercise: Hold out your right hand, place fingers together, and compare the length of your index (first) finger and ring (third) finger. The hormone "testosterone" is linked with masculine traits. The amount of testosterone exposed to in the womb affects finger length. The hi

Mendelian Inheritance Traits in Animals

The full problem is attached as a Word document, containing figures and pictures. The problem concerns a dominant and a recessive gene in lizards that affect the skin color of the lizard. The frequency of these genes in two different habitats is presented, and answers are given to several questions relating to the reasons

Inheritance of color blindness

A woman referred to as individual A marries a man, individual B. Both have normal color vision. They have 3 children. Child AB1 is a son with normal color vision. Child AB2 is also a son but he is red green colorblind. The third child, son AB3, is red green colorblind as well. AB1 son marries a woman, S, with normal vision.

Whether an allele is dominant or recessive depends on

Whether an allele is dominant or recessive depends on a. how common the allele is relative to other alleles b. whether it is inherited from the mother or father c. which chromosome it is on d. whether it or another allele is expressed when they are both present

Why are sex-linked diseases more common in men than in women?

Why are sex-linked diseases more common in men than in women? a. Men acquire two copies of the defective gene during fertilization b. Men who inherit only one copy of the harmful recessive gene will have the disease c. The sex chromosomes are more active in men than in women d. both B and C

Pattern of inheritance

All of the offspring of a white hen and a black rooster are grey. The simplest explanation for this pattern of inheritance is: a. Incomplete dominance b. Multiple alleles c. Sex linkage d. Independent assortment

Mendelian ratio

In order to get the expected Mendelian ratio in a monohybrid cross, it is important to be able to observe: a. four offspring b. one for each box in the Punnett square c. many offspring d. one phenotype for each genotype that is expected e. more recessive phenotypes than dominant phenotypes