Answer;
-Correlational; experimental
Two main types of designs used specifically in human lifespan studies are correlational and experimental.
Explanation;
-Psychological studies vary in design. In correlational studies a researcher looks for associations among naturally occurring variables, whereas in experimental studies the researcher introduces a change and then monitors its effects.
-An experiment isolates and manipulates the independent variable to observe its effect on the dependent variable, and controls the environment in order that extraneous variables may be eliminated. Experiments establish cause and effect. A correlation identifies variables and looks for a relationship between them.
The virus may have not developed fully the first time.
Answer:
tumor suppressor gene
Explanation:
A tumor suppressor gene is capable of modulating cellular processes during cell division and/or replication, thereby avoiding uncontrolled cell proliferation and tumor development. For example, the p53 gene is a tumor suppressor gene that encodes a protein (p53) which is well known to regulate critical cellular processes such as, for example, cell cycle arrest and programmed cell death (apoptosis). Moreover, breast cancer genes BRCA1 and BRCA2 are tumor suppressor genes that regulate the repair of damaged DNA through the Homologous recombination (HR) pathway. In consequence, mutations in BRCA1 and BRCA2 genes can increase the risk of developing breast cancer.