Stages of Meiosis and Mitosis
Mitosis and Meiosis
Evolution
Mechanism of Evolution
Speciation
Phylogeny
Animal Behavior
100
During which stage of mitosis do sister chromatids separate and move to opposite poles of the cell?
Anaphase
100
What is the difference between asexual reproduction and sexual reproduction?
Asexual Reproduction: A single individual is the sole parent and there is no fusion of gametes.
Sexual Reproduction: Fusion of gametes with usually two parents (not always the case, can you think of an example where there is only one parent with fusion of gametes?)
100
Artificial selection has been used for centuries to breed animals and plants with desirable traits.
How does artificial selection differ from natural selection, and what evolutionary consequences might arise from long-term artificial selection in a species?
Artificial selection is a process where humans intentionally breed organisms to enhance specific traits, such as size, color, behavior, or productivity. In contrast, natural selection is driven by environmental pressures, where traits that improve survival and reproduction become more common over time.
Consequences:
Evolutionary Consequences of Long-Term Artificial Selection:
Reduced genetic diversity, Exaggerated traits that may compromise health or survival (e.g., bulldogs with breathing issues), Potential for speciation if artificially selected populations become reproductively isolated.
100
Why is phenotypic variation important for evolution to occur?
Without phenotypic variation, natural selection has nothing to "select", and evolution would stall.
100
What is speciation?
When a group within a species separates from other members of its species and develops its own unique characteristics.
100
A phylogenetic tree shows what?
The evolutionary relationships among species
100
What is a behavior?
An action carried out by the muscles under control of the nervous system
200
What key event occurs during prophase I of meiosis that does not occur in mitosis?
Homologous chromosomes pair and undergo crossing over
200
What will the genotype and phenotype be of an offspring that reproduced asexually?
Offspring that are produced asexually are genetic clones of their one parent, their phenotype should also be the same.
200
Which of the following best describes the concept of acquired inheritance, and how does it differ from Darwin’s theory of natural selection?
A. Acquired inheritance suggests traits gained during an organism’s lifetime can be passed to offspring, while natural selection relies on inherited genetic variation.
B. Acquired inheritance explains evolution through random mutations, while natural selection focuses on environmental pressures.
C. Acquired inheritance and natural selection both rely on DNA mutations passed through gametes.
D. Acquired inheritance is the modern explanation for evolution, replacing Darwin’s outdated ideas.
A. Acquired inheritance suggests traits gained during an organism’s lifetime can be passed to offspring, while natural selection relies on inherited genetic variation.
200
Why must variation be heritable for evolution by natural selection to occur?
For natural selection to drive evolution, the differences (variations) among individuals must be genetically inherited.
200
How does one species arise from another?
A. By individuals choosing to change their traits during their lifetime
B. Through reproductive isolation and genetic changes that prevent interbreeding
C. When all members of a species migrate to a new location
D. By learning new behaviors from other species
B. Through reproductive isolation and genetic changes that prevent interbreeding
200
What is sister taxa?
Groups of organisms that share a common ancestor not shared by any other groups in the tree.
200
How does prey density influence an animal’s foraging strategy
Higher prey density often leads to more efficient foraging, while low density may force animals to adapt their tactics or expand their search area.
300
Which of the following best describes what occurs during telophase I of meiosis?
A. Homologous chromosomes pair up and undergo crossing over.
B. Sister chromatids separate and move to opposite poles.
C. Two haploid nuclei form, each with half the original chromosome number.
D. Chromosomes line up single file along the metaphase plate.
C. 
Two haploid nuclei form, each with half the original chromosome number.
300
Why do prokaryotes reproduce asexually through binary fission and not mitosis?
Prokaryotes do not have a nucleus and only have a single strand of DNA.
300
According to Darwin’s theory of evolution, what is the role of adaptation in a population’s survival?
Adaptations are inherited traits that increase an organism’s chance of survival and reproduction in a specific environment.
300
Why is variation in traits important for reproductive success in a population?
Phenotypic variation means individuals differ in traits like size, color, or behavior. In a given environment, some of these traits may offer an advantage, such as better camouflage or resistance to disease, leading to greater survival and reproductive success. Over time, these advantageous traits become more common in the population through natural selection.
300
What is sympatric speciation, and how does it differ from allopatric speciation?
Allopatric: Populations evolve into new species due to geographic separation.
Sympatric: Gene flow is stopped between two population that live in the geographic area.
300
What is a basal taxon?
A lineage that diverges from all the other members of its group early in the history of the group.
300
How does handling time influence an animal’s decision to pursue certain prey?
Handling time affects prey choice by influencing energy efficiency. Animals prefer prey that offers high energy gain with low handling effort to maximize net energy gain.
400
In which stage of mitosis do chromosomes align at the center of the cell?
Metaphase
400
Why does mitosis not produce a haploid cell? Why does Meiosis not produce diploid cell?
Mitosis: It's purpose is to create an identical daughter cell from a diploid parent cell.
Meiosis: Has two divisions which reduces the number of chromosomes and results in four genetically different haploid cells.
400
Which of the following best describes how artificial selection supports Darwin’s theory of evolution?
A. It shows that traits acquired during life can be inherited.
B. It demonstrates that humans can influence evolution by selecting desirable inherited traits.
C. It proves that all organisms evolve naturally without environmental pressure.
D. It shows that mutations are always harmful and must be removed.
B. It demonstrates that humans can influence evolution by selecting desirable inherited traits.
400
According to the good gene hypothesis, why might a peahen choose a peacock with a large, colorful tail?
Because it signals strong genes that may benefit her offspring
400
Which scenario best illustrates behavioral isolation?
A. Two bird species live in different forests
B. One group of frogs mates using a high-pitched call, while another uses a low-pitched call
C. A population of insects is separated by a river
D. Two fish species feed at different depths
B. One group of frogs mates using a high-pitched call, while another uses a low-pitched call
Autopolyploid: Individual that has more than two chromosome
sets that are all derived from a single species
Polyploidy: A condition that occurs when cell division results in extra sets of chromosomes
400
A paraphyletic group:
A. Includes all descendants of a common ancestor
B. Includes an ancestor but not all its descendants
C. Includes species from different ancestors
D. Is the same as a clade
B. Includes an ancestor but not all its descendants
400
What behavioral adaptations help animals reduce predation risk while foraging?
Animals reduce predation risk while foraging by staying alert, foraging in groups, choosing safer habitats, and feeding during low-risk times.
500
What distinguishes anaphase I of meiosis from anaphase of mitosis?
Homologous chromosomes separate in meiosis I
500
How does one gamete from each of two parents
join to produce a diploid organism?
Fertilization: The process by which two haploid gametes, produced by each parent, are fused together to create a diploid cell called a
zygote
500
How did Thomas Malthus’s essay on population growth influence Darwin’s theory of natural selection?
It emphasized that more offspring are produced than can survive, leading to competition for resources.
500
How might the good gene hypothesis explain the evolution of costly or exaggerated traits that don’t seem to help survival?
The good gene hypothesis explains that costly or exaggerated traits, like a peacock’s large, colorful tail can evolve because they signal genetic quality to potential mates. Even though these traits may reduce survival (e.g., making the peacock more visible to predators), they increase reproductive success by attracting more mates.
500
Why does sexual selection lead to sympatric speciation?
Mate preferences can cause reproductive isolation without physical barriers by leading individuals within the same population to consistently choose specific traits in mates, which reduces gene flow between groups and eventually splits them into distinct species.
500
Which group is formed based on similar traits but not shared ancestry?
A. Monophyletic
B. Paraphyletic
C. Polyphyletic
D. Clade
C. Polyphyletic
500
How do differences in reproductive energy investment affect lifetime reproductive success in males vs. females?
Females typically invest more energy in reproduction, which leads to fewer but higher-quality offspring, while males invest less per mating and often pursue quantity over quality, resulting in different strategies for maximizing lifetime reproductive success.
600
Which phase of meiosis II is most similar to mitosis?
All of meiosis II
600
A diploid organism has a mutation that disrupts spindle fiber formation. How would this mutation differentially affect mitosis and meiosis during anaphase, and what are the likely consequences?
A. Mitosis would proceed normally, but meiosis would fail to produce any gametes.
B. Both mitosis and meiosis would experience disruption of the proper segregation of chromosomes, but only meiosis could result in heritable genetic disorders.
C. Mitosis would result in gametes with abnormal chromosome numbers, while meiosis would affect somatic cells.
D. Spindle fiber defects only impact meiosis, leading to cancerous cell growth.
B. Both mitosis and meiosis would experience disruption of the proper segregation of chromosomes, but only meiosis could result in heritable genetic disorders.
Explanation:
In mitosis, defects lead to aneuploid somatic cells, which may cause cell malfunction or cancer.
In meiosis, defects cause nondisjunction, producing gametes with abnormal chromosome numbers.
600
Darwin observed that finches on the Galápagos Islands were similar in appearance but had different beak shapes suited to their environments.
What hypothesis did he develop based on this observation?
Finches share a common ancestor, but new species arose through adaptations to different environments.
600
How do mutations lead to new traits in a population?
Mutations lead to new traits in a population by introducing changes in the DNA sequence of an organism’s genes. These changes can alter how proteins are made, which in turn can affect an organism’s physical traits—or phenotype.
600
What is allopolyploidy, and how does it differ from autopolyploidy?
Allopolyploidy = hybridization between species. Two different species interbreed and produce hybrid offspring.
Autopolyploidy = chromosome duplication within one species.
600
What is the difference between genus and species in biological classification?
Genus = broader category that includes multiple species.
Species = specific organism type within that genus.
600
How does certainty of paternity influence the level of paternal care in animals?
A. Higher certainty of paternity often leads to increased paternal care, as males are more likely to invest in their own offspring.
B. Certainty of paternity has no effect on paternal care in any species.
C. Lower certainty of paternity always leads to more paternal care to compensate.
D. Paternal care is only influenced by environmental factors, not paternity certainty.
A. Higher certainty of paternity often leads to increased paternal care, as males are more likely to invest in their own offspring.
700
What happens during telophase in both mitosis and meiosis?
Nuclear envelopes reform around separated chromosomes
700
In sexually reproducing organisms like humans, the life cycle alternates between diploid and haploid stages.
Which of the following best explains how this alternation is maintained across generations?
A. Mitosis reduces the chromosome number in somatic cells, while meiosis restores it in gametes.
B. Fertilization restores the diploid number by combining two haploid gametes, and meiosis ensures gametes remain haploid.
C. Meiosis doubles the chromosome number in gametes, and mitosis maintains it in offspring.
D. Somatic cells alternate between haploid and diploid states depending on environmental conditions.
B. Fertilization restores the diploid number by combining two haploid gametes, and meiosis ensures gametes remain haploid.
700
Why do unrelated species sometimes evolve similar traits?
Because of convergent evolution. Unrelated species sometimes evolve similar traits because they face similar environmental challenges, leading them to develop comparable adaptations.
700
How did the fossil record support Darwin’s ideas?
The fossil record supports Darwin’s ideas by showing that life has changed over time, with older fossils revealing simpler organisms and newer ones showing more complex forms, evidence of gradual evolution through natural selection.
700
Why might hybrids have lower fitness than their parent species?
Hybrids might have lower fitness than their parent species because they often inherit incompatible traits or genes that reduce their ability to survive or reproduce effectively.
700
How do shared derived characteristics help define clades in a phylogenetic tree?
Shared derived characteristics help define clades in a phylogenetic tree by identifying traits that are unique to a common ancestor and all its descendants.
700
Why do polygamous species often show strong sexual dimorphism?
A. Because both sexes invest equally in reproduction and appearance
B. Because males and females live in different environments
C. Because males compete for access to multiple mates, leading to selection for traits like size or ornamentation
D. Because polygamous species have shorter lifespans and need to reproduce quickly
C. Because males compete for access to multiple mates, leading to selection for traits like size or ornamentation