Evolutionary Relationships — Cumulative exam Answers

What will happen to the frequency of the recessive allele for the HbS gene when there is an outbreak of malaria?

What is the primary source of energy in a food chain?

If Mendel had crossed a true breeding dominant plant with a true breeding recessive plant, in which of the three generations is the recessive trait visible?

The tundra ecosystem of Alaska is known as a “cold desert.” It receives very little precipitation, about four inches annually. However, it is rich in wetlands due to permafrost, which traps moisture close to the surface. The temperatures vary widely, also producing persistent winds. Although treeless, the Arctic tundra is an abundant ecosystem. Many organisms find their niche here including many migratory bird species and mammals such as caribou, foxes, bears, and small rodents. Which factor of the tundra ecosystem is biotic?

Which of the following describes a positive feedback loop?

Some flowering plants appear to have offspring that have traits that are intermediate between those of the parents. Which type of dominance is exhibited by the offspring?

Look at the two images of cells.Which of the following statements best describes what can be seen in the images?

Cystic fibrosis is a genetic disorder. It is a recessive trait that is determined by two alleles. Suppose two parents each carry at least one recessive allele, but neither of them has cystic fibrosis. Which statement reflects the likelihood of a child of these parents having cystic fibrosis?

Consider the cladogram.According to the cladogram, which characteristic was used to separate bony fish from amphibians?

Which is the largest gland in the body?

It can be seen on a cladogram that modern birds and reptiles share a common ancestor. Select the piece of evidence that best supports this idea.

The body obtains sugar from food. Which system most directly affects blood sugar levels?

Actinobacteria sp. are organisms called chemoorganohetereotrophs. They do not use oxygen to breathe. They break down organic material and convert it to inorganic material.Which part of the carbon cycle does this describe?

In roses, red flowers and long stems are dominant traits. A rose plant that is homozygous for both red flowers and long stems is crossed with a rose plant that is heterozygous for red flowers and homozygous for short stems. What percentage of the offspring will exhibit red, long-stemmed flowers?

Consider the group of giraffes in the image below.Which statement about the giraffes explains their evolution based on Charles Darwin’s main points?

Which of these are most likely homologous structures? bat wing dragonfly wing Tyrannosaurus arm

The data in the graph are the result of a paramecium being placed in a hypertonic salt solution.Based on the data in the graph, which would most likely happen if the paramecium were placed in distilled water?

A conservation biologist has determined the status of the ecosystems in a protected area, as shown in the table below. Based on the table, which part of the pie chart represents secondary succession?Status of ecosystemsPercentage of protected areaPrimary succession10Secondary succession30Barren land5Established community55

The diagram represents a dihybrid cross between two pea plants heterozygous for both seed color and seed shape.What is the phenotypic ratio of the offspring?

Mendel was able to study seven traits in all the pea plants in each generation. Which of his hypotheses allowed him to analyze each trait separately?