Answer:
D. They define geological periods because scientists use them as reference points for tracking the history of the earth.
Explanation:
Catastrophic events related to changes in geological timeline are very useful in defining geological periods.
These events have very significant appearance in the geological record and can be used to determine the history of the earth.
The catastrophic events usually culminates into extinction cycles or termination of some organisms from the earth surface.
Geologists use these events that are often wide spread to delineate geological periods.
The given blank can be filled with cells.
The extracellular matrix is the protective tissues present as a coating of the cells. Both animals as well as the plant cells have the extracellular matrix, this coating provides support, biochemical protection and mechanical protection from the external environment of the cells. In the plant cells, the cell wall is a type of extracellular matrix.
Answer:
Despite there being many different types of epithelial tissue all epithelial tissue have just five characteristics, these are cellularity, polarity, attachment, vascularity, and regeneration. Cellularity as the name suggests means that the epithelium is made up almost entirely of cells.
Answer:
Co-dominance because he expresses both of the alleles simultaneously
Explanation:
The ABO blood group system is used by humans. This blood group type is controlled by multiple alleles. Alleles A and B are both dominant over allele O but are co-dominant. Co-dominance is a type of inheritance pattern in which two alleles of a gene both express themselves i.e. neither is recessive.
This is the case of this family whose parents have a genotype of AO (blood type A) and BO (blood type B) respectively. The children have blood types A, B, and AB. However, the child with genotype AB possesses both the A and B allele, which are both expressed in his blood group (phenotype), hence, it can be said that the child is exhibiting CO-DOMINANCE for the blood group trait.
<span>D how species change over time</span>