Match the selected genotypes with the appropriate description.
For natural selection to cause evolution, it must select for or against one or more of the genotypes for a trait. In the simple case of a trait that is determined by a single gene with two alleles, there are five combinations of genotypes that nature can select:
1. either homozygote (AA or aa but not both)
2. both homozygotes (AA and aa)
3. either homozygote and the heterozygote (AA and Aa or aa and Aa)
4. the heterozygote (Aa)
5. all alleles (AA, Aa, and aa).
ITEM BANK: Move to Top
Selection against all genotypesSelection against the heterozygoteSelection against the heterozygote and one homozygoteSelection for the heterozygote
The CCR5-delta 32 gene provided immunity to a deadly disease of bacterial origin, bubonic plague. . People who are homozygous for the CCR5-delta 32 gene variant are completely immune, while heterozygotes only have partial immunity and homozygous recessive have none.
Selection for the homozygous dominant (AA)
Sickle cell disease - homozygous dominant contract malaria; homozygous recessive die young from sickle cell; heterozygotes immune to malaria.
An example of disruptive selection because both extremes are favored to survive.
This type of selection will result in extinction of the species as all genotypes are at a selective disadvantage.
Huntington's disease is a single gene disorder caused by a malfunctioning gene on chromosome 4. It is an autosomal dominant disease, which means that only one copy of the gene needs to be defective.
Solved
Show answers
More tips
- A Auto and Moto Discovering the Leader: What is the Most Expensive Car in the World?...
- H Health and Medicine Hangover: How to Get Rid of It Quickly?...
- S Style and Beauty How to Choose the Right Fur Coat and Avoid Regrets?...
- C Computers and Internet How to Create a Folder on Your iPhone?...
- G Goods and services How to sew a ribbon: Tips for beginners...
- F Food and Cooking How to Make Mayonnaise at Home? Secrets of Homemade Mayonnaise...
- C Computers and Internet Which Phone is Best for Internet Surfing?...
- F Food and Cooking Everything You Need to Know About Pasta...
- C Computers and Internet How to Choose a Monitor?...
- H Horoscopes, Magic, Divination Where Did Tarot Cards Come From?...
Answers on questions: Biology
- B Biology Which of the following farming activities is MOST helpful to the environment? A) rotating crops to reduce soil loss B) clearing land to grow more crops C) damming a river...
- B Biology Suppose you created a set of Instruments using water and drinking glasses. You need a note with a very low pitch to complete a certain song-what should you do? Pour out...
- B Biology Compare some structural adaptations of a giraffe with those of an elephant....
- B Biology Which sentences describe the cyclone device? A cyclone device accumulates fine particulates from the air by making a dirty air stream flow in a spiral path inside a cylindrical...
- B Biology The pH indicator bromothymol blue is blue in an alkaline solution and yellow in an acidic solution. A slight increase in acidity, such as when CO2 gas is added, causes...
- B Biology Whay is a mushroom niche...
- B Biology The law of segregation states that there are two factors controlling a given characteristic, one of which dominates the other, and these factors separate and go to different...
- B Biology Hwe-amvn-grtjoinforvirtualsex...
- B Biology Who explained why the most fit individuals of a species tend to survive?...
- B Biology Former volcanoes now under the sea are called...
Ответ:
I think the best answer here is "C"