Develop diseases because they have little genetic variation.
Answer: Layer a is 500 million years old.
Explanation:
Trilobite is a member of the group of extinct arthropods found as fossils and they can be identified by the three-lobed as well as three segmented forms. These were the marine animals. These were appeared initially in the Cambrian Period. They used to live 542 million years ago so the fossils can be estimated to be aged of 500 above years old. These animals used to dominate in the sea area.
The<u> repressor </u>is a type of regulator protein that binds to a region of DNA in the promoter of a gene called the operator and prevents transcription from taking place.
In the field of science, a regulator protein can be described as a kind of protein that affects the transcription of a gene by having an influence on particular DNA sites. The rate of synthesis of various proteins is controlled by the regulator proteins.
A repressor is a kind of regulator protein that prevents the transcription of a particular gene. When the rate of a protein in the body has reached normal, the transcription of the protein needs to be stopped in order for more protein of that kind to be formed. The repressor binds itself to the operator region for the gene, hence stopping the transcription process until the protein is required again.
To learn more about repressor, click here:
brainly.com/question/13799037
#SPJ4
Answer: Pedigrees can show someone is a carrier for diseases by determining which parent, if not both, is either dominant or recessive. Each child must have a letter from their parent then that will determine if someone gets a disease or not then it goes on from generation to generation. However, they can be carriers of the trait, and if they are carriers, their male children will be colorblind. On a pedigree, carriers are represented either by a half-shaded symbol or a shaded dot in the middle of the symbol. brainliest??
Explanation: