The smallest unit of classification is species.
Gene–environment interaction or genotype–environment is when two different genotypes respond to environmental variation in different ways. A norm of reaction is a graph that shows the relationship between genes and environmental factors when phenotypic differences are continuous.
Answer:
Weather conditions
Explanation:
Food can be limited based on location, however, scientists can control what kind of food it is. Soil can be tested and experimented on. There can be a lot of it and different kinds. Space is fought over because of territories and is limited compared to how many people and animals there are. Weather is not something that can be controlled in an experiment since it is sporadic.
Answer:
A. amount of food available
Explanation:
An experiment consists of two types of variables, independent and dependent. Value of independent variable is decided by the person doing the experiment and is independent of experimental conditions. Value of dependent variable is dependent on the independent variable. It can not be altered by the person doing experiment.
Here, it is given that mice receive variable amount of food each day and their lifespan is recorded. Since the amount of food is decided already it is the independent variable. The lifespan is expected to depend on the amount of food hence it is the dependent variable.
The answer could possibly be natural selection or survival of the fittest
