Biology semester test

Make punnett squares to support your answer. In pea plants, yellow seed color (Y) is dominant to green see color (y); round seeds (R) are dominant to wrinkled seeds (r). What is the probability that parents with the genotypes YyRR and YYRR will produce an offspring with the genotype YYRR?

0.5

The trait for purple flowers in pea plants (P) is dominant to the trait for white flowers (p). What is the probability of both parents donating a recessive p allele?

0.5

The trait for purple flowers in pea plants (P) is dominant to the trait for white flowers (p). What is the probability that the heterozygous parent will donate a recessive p allele?

0.5

The trait for purple flowers in pea plants (P) is dominant to the trait for white flowers (p). What is the probability that the homozygous-recessive parent will donate a recessive p allele?

1

Two heterozygous, wirehaired vizslas were crossed. The genotypes of their potential offspring are shown in the Punnett square in the below. What is the phenotypic ratio of wire-coated to smooth-coated offspring? What is the genotypic ratio of homozygous dominant to heterozygous to homozygous recessive offspring? Wire-coated is dominant.

1 to 2 to 1

Fruit fly gametes each have 4 chromosomes representing 2 to the 4th power, or 16, possible chromosome combinations. How many chromosome combinations could result from fertilization between a fruit fly egg and a sperm cell.

256

Two heterozygous, wirehaired vizslas were crossed. The genotypes of their potential offspring are shown in the Punnett square in the below. What is the phenotypic ratio of wire-coated to smooth-coated offspring? Wire-coated is dominant.

3 to 1

The results of a study on the effects of mutagen on bacteria had the following results. Some bacterial cultures were exposed to the mutagen, some were not. Which culture was most likely exposed to the mutagen?

350 bacteria cells

Which event shows conditions that lead to natural selection?

A crab produces millions of offspring in a year, but few survive to adulthood.

__________ in a DNA sequence would correspond to a "stop" codon.

ATC

If the original DNA sequence reads TAG, the mRNA codon would be 1.__________ and the corresponding amino acid would be 2.__________.

AUC; Isoleucine

Which of these are elements of the cell theory? Select all that apply.

All cells come from other cells. Cells are the basic units of life. All living things are made of cells.

Which of these is an example of an environment in which natural selection would not occur?

All offspring have the same chance of survival.

Circle the letters of the three examples of innate behavior.

All spiders of a certain species make webs of a similar shape. A turtle immediately crawls to the ocean after hatching from an egg. Male penguins know how to care for an egg, although they have never observed this behavior.

Examine the image of founding beetle populations. What may be observed in the descendant populations that arise from a small number of founding individuals? Select all correct answers.

Allele frequencies in one descendant population may be very different from those in another descendant population. Some alleles may be completely lost in one or more descendant populations. The genetic variation of the descendant population is usually lower than in the original population.

How did the invention of the light microscope lead to the development and refinement of cell theory over time?

As microscopes became more powerful, scientists could see additional structures within the cell.

Which statement best explains why a group of cells functions better than one large cell?

As the cell gets larger, the distance from the nucleus to the membrane increases, thereby reducing its ability to function.

in a DNA sequence would lead to the polypeptide chain valine-methionine-phenylalanine.

CAGTACAAG

Which hypothesis about cells was later found to be wrong by scientists?

Cells are formed spontaneously by free-cell formation.

What is the importance of codons during the process of protein synthesis?

Codons code for the particular amino acids that get assembled.

A biologist studying wolves has collected data on the mass of meat caught per day from hunts by packs varying in size from 2 to 15 wolves. The data show that as pack size increases, the mass of meat available per pack member per day increases. Which additional study would provide evidence that pack hunting provides an advantage?

Compare the average number of pups per litter that reach reproductive age for wolf packs of different sizes.

Haploid Cells

Contain single chromosomes, each from one parent Make fertilization possible Result from meiosis

An insect that lives on an island can have either a light blue or a dark blue color. A researcher has found that the percent of the population that is light blue has increased from 35% to 72% in the last decade. Which of these statements, if true, would least help to explain this change?

Darker-colored females are able to lay more eggs than lighter-colored females.

Which of the following statements best describes how genes relate to traits?

Genes code for the production of specific proteins. These proteins lead to different traits.

Which of the following questions can be answered by Mendel's Law of Segregation?

How can a plant that is heterozygous for height (Tt) have both tall and short offspring?

Franklin, Watson, and Crick's model of DNA shows a double helical structure where two strands of DNA run antiparallel to each other. How does this structure cause the number of purines to equal the number of pyrimidines as observed by Chargaff?

If adenine is on one strand, thymine must be on the other strand.

Many changes in the environment can benefit some species while causing others to go extinct. Which of these is not an example of how environmental change can be both beneficial and detrimental?

Increased phosphate in rivers increases algae growth while providing more food for certain fish.

What stage of cell division is this?

Interphase

The model shows what happens to chromosomes during a certain part of the cell cycle. Which of these is a reason that the chromosomes in the cell have two chromatids?

It allows the cell to divide into genetically identical daughter cells.

In some species of anglerfish, the male fish are parasites of the females. When a male anglerfish comes into contact with a female, he bites her body and eventually fuses with her, losing all internal organs except for his testes. Which of these best explains why this relationship exists?

It increases the reproductive success of anglerfish females and males.

A scientist presented the information in the illustration as part of a report on the evolution of species. How does the information support the claim of common ancestry?

It shows many similar traits exist during development.

The image shows a fossil of Archaeopteryx, thought to be the first fully feathered dinosaur. How does this piece of evidence support the theory of evolution?

It suggests that birds and dinosaurs have a common ancestor.

Certain lizards dig burrows to avoid the heat of the day and emerge at night to hunt. When there are large numbers of these lizards, their burrows may intersect with each other. Raccoons are beginning to prey mainly on these lizards. The raccoons catch the lizards as they emerge from their burrows. Which change could occur if this continues?

Lizards that use interconnected burrows to avoid raccoons will be more likely to survive and pass on their genes to offspring, thus increasing traits in the population that promote group living\

Transcription and translation, the two main processes involved in protein synthesis, have distinct molecular inputs and outputs. Which statement about inputs and outputs in these processes is true?

Messenger RNA is an output for the process of transcription and an input for the process of translation.

A person cuts their finger. How does the process of mitosis help to repair the wound?

Mitosis forms new cells in the area where the old ones were damaged.

Which of the following statements describe differences between mitosis and meiosis? Select all correct answers.

Mitosis is involved in asexual reproduction, and meiosis is involved in sexual reproduction Mitosis produces diploid cells, and meiosis produces haploid cells Two daughter cells are produced by mitosis, and four daughter cells are produced by meiosis

Can a parent pass on a mutation in a kidney cell to his child? Select all correct answers.

No, because a kidney cell is a body cell. Only mutations in germ cells can be passed on from parent to child.

A guard bee's job is to protect the hive from intruders, a job that can lead the guard bee to sacrifice its own life. If the guard bee cannot reproduce, how do genes for altruism increase in the population?

Other members of the colony with the same genes will be able to survive as a result of the guard bee's efforts and reproduce, thus, passing on the genes.

Diploid Cells

Result from mitosis Are described as 2n Contain chromosomes in pairs, one from each parent

A species of newt defends itself against predators by producing a toxic compound in its skin cells. Biologists observed that only snakes living in regions that overlap with the newt had a resistance trait to the toxin. Which statement best explains the cause of this resistance

Some snakes living in the area of the newt happened to have resistance to the toxin, which allowed these few to survive and pass on the resistance trait to their offspring.

A strand of RNA has the sequence AUUGCGCGAA. What explanation can be made about how this strand came to be?

The RNA strand was transcribed from a DNA strand with the sequence TAACGCCTT.

After fertilization, a single cell divides successfully to form a multicellular structure. What happens next in order for this structure to develop tissues and organs to meet the needs of the organism?

The cells undergo differentiation into particular body parts.

Although flight evolved separately in bats and birds, their forelimbs are considered homologous. What does this information suggest about the relationship between bats and birds?

The fact that birds and bats have the same bones in their wings shows that they must be closely related.

Epidermolysis bullosa is a disease characterized by very delicat skin that easily blisters upon scratching or being exposed to the slightest friction. The disease is caused by a missense mutation. Which statement describes the mutation that causes epidermolysis bullosa?

The mutation is caused by a change in one of the amino acids.

Which of the following statements best describes why a recessive trait is not observed in the offspring of a cross between a homozygous-dominant and a homozygous-recessive parent?

The offspring will be heterozygous, and the dominant allele masks the appearance of the recessive allele.

Annalisa is studying the fossilized remains of extinct organisms shown. She notices that each of these species has a segmented body, similar to modern arthropods, such as lobsters and spiders. Which statement is the most likely explanation for this observation?

The organisms share a common ancestry with modern arthropods

The graph shows the distribution of a trait in an animal population. If the species were to undergo stabilizing selection in which extreme phenotypes were selected against, how would the graph be expected to change?

The peak would become taller and narrower.

Mendel's F1 generation of pea plants were heterozygous. What does this mean?

The plants had two different alleles for the same trait

DNA is the hereditary molecule that determines hair color in humans. However, the DNA molecule itself is colorless. How does DNA determine the hair color of individuals?

The sequence of DNA determines the structure of proteins, which direct genotypes

Curves A and B represent the frequency and length of two populations of earthworms. How are these two populations different?

There is less variation in individuals found in population A than in population B

A stem cell in an animal divides by mitosis. Which statement is true about the two daughter cells?

They each have the same DNA sequences.

Why did Mendel remove the stamens of some pea plants during his first experiments? Select all correct answers.

To prevent reproduction from occurring to control which parent plants were allowed to reproduce to prevent self-fertilization of the pea plants

A researcher is studying the rates of mitosis of different cell types. Which of these cell types would most likely have the highest rate of mitosis?

a cell in the lining of the intestine

GCC in a DNA sequence after transcription and translation would correspond to the amino acid 4.__________.

arginine

Individuals from two different species of firefly, species A and species B, are brought together. It is determined that the females from species A do not recognize the mating signals flashed by males of species B, and females from species B do not recognize signals from males of species A. Based on this finding, what past phenomenon may have led to speciation in these fireflies?

behavioral isolation

Scientists have discovered several species of insect that all contain the DNA sequence ATTACGCGATC on their second chromosome. What does this evidence suggest?

common ancestry among organisms

Before the genetic code could be understood, scientists needed to know that a codon is composed of three nucleotides. This situation is an example of the

cumulative nature of scientific evidence.

A flowering plant varies in color from white to deep red. A deer population that feeds on the plant is increasing. The deer are attracted to red flowers and consume fewer of the white flowering plants. Which type of selection occurs in this case?

directional selection

What evidence would be needed to support an explanation about how RNA is formed from a DNA molecule during protein synthesis?

evidence that shows the original DNA strand and the resulting RNA strand after transcription has occurred

Which is not a factor that could increase the rate of mutations in a cell?

exposure to a chemical carcinogen

Populations can become extinct for many reasons. Which of these occurrences may cause a population to become extinct? Circle the letters of all the correct answers

extensive flooding from unusually heavy rainfall a decrease in dissolved oxygen in a lake ecosystem an increase in average ocean temperatures throughout the year

A student uses string to model four pairs of homologous chromosomes in a parent cell. Each chromosome pair is a different color. Which model would best show the genetic makeup of a daughter cell produced by meiosis?

four strings, each a combination of different colors

A scientist has found fossils of an organism that she suspects is related to a living vertebrate species, but it has different physical characteristics. The fossil is dated at 10 million years old. The scientist wishes to look for a transitional species between the fossil organism and the living vertebrate species. Which location would be the best to find fossils of a transitional species?

in sedimentary rock that is dated at 5 million years old

Explain how mutations contribute to genetic diversity.

increase genetic diversity changes the genetic makeup of organisms increases variety within a population all of the above are true

Which area of biology provides evidence that organisms are continuing to evolve in modern times?

investigations leading to new vaccines every year to fight infections from the influenza virus

what stage of cell division is this

metaphase

Which stage of cell division is this?

prophase

Herring are small ocean fish that often swim together in large schools. Though this behavior uses significant energy and can increase competition for resources, what advantages might the evolution of schooling behavior provide for herring? Select all correct answers.

the ability for many individuals to spot predators greater efficiency in searching for food together confusing potential predators by appearing to be one large animal

What factor is most important in the cell differentiation that occurs during the metamorphosis of a tadpole into a frog or a caterpillar into a butterfly?

the expression of different genes at different times

Two heterozygous, wirehaired vizslas were crossed. The genotypes of their potential offspring are shown in the Punnett square in the below. What genotype has a 100% chance of expressing a recessive allele? Wire-coated is dominant.

ww