Science as a Process and Theories
48 Questions
0 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to Lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What defines an individual as being 'more fit' in the context of natural selection?

  • The relative number of viable offspring produced (correct)
  • The longevity of the individual
  • The individual's strength and size
  • The intelligence of the individual

Which statement best describes adaptation?

  • A process where individuals become stronger
  • A heritable trait that decreases fitness
  • A heritable trait that increases relative fitness (correct)
  • A random change in an individual's traits

What misconception is commonly associated with the phrase 'survival of the fittest'?

  • It implies all individuals in a population will survive equally
  • It refers solely to the survival of the strongest individuals (correct)
  • It means only the oldest will survive
  • It refers to reproductive success as an essential factor

What role do humans play in artificial selection?

<p>They act as the selecting agents driving evolutionary changes (B)</p> Signup and view all the answers

How is fitness calculated in the context of natural selection?

<p>By counting the total number of offspring produced (B)</p> Signup and view all the answers

Why is it incorrect to assume that all adaptations occur quickly?

<p>Adaptation is a gradual process that can take time (A)</p> Signup and view all the answers

Which of the following best explains the concept of natural selection?

<p>It involves the reproductive success of individuals with favorable traits (B)</p> Signup and view all the answers

In terms of breeding, what advantage does a king salmon producing 100 eggs have over others producing thousands?

<p>Higher relative fitness compared to others (D)</p> Signup and view all the answers

What is the primary result of the modifications in the spinal column and musculature for an upright stance?

<p>Increased likelihood of chronic problems (B)</p> Signup and view all the answers

Which term describes an adaptation arising from the modification of an ancestral trait?

<p>Contrivance (B)</p> Signup and view all the answers

How can one determine if an adaptation is truly novel?

<p>It resembles no previous traits (D)</p> Signup and view all the answers

What is the term used to describe the number of sets of chromosomes a cell contains?

<p>Ploidy (C)</p> Signup and view all the answers

What does the term 'exaptation' refer to?

<p>A previous trait that becomes useful under new conditions (C)</p> Signup and view all the answers

Which of the following statements about homologous chromosomes is true?

<p>One is inherited from each parent. (C)</p> Signup and view all the answers

Which of the following is NOT a characteristic of adaptations?

<p>Completely new traits (A)</p> Signup and view all the answers

In which type of organism is a haploid individual primarily observed?

<p>Fungi (B)</p> Signup and view all the answers

What process is responsible for the production of gametes?

<p>Meiosis (A)</p> Signup and view all the answers

What is the relationship between adaptations, contrivances, and exaptations?

<p>Contrivances and exaptations are types of adaptations (B)</p> Signup and view all the answers

Which statement is true regarding natural selection and skeletal design?

<p>Natural selection modifies existing skeletal designs (A)</p> Signup and view all the answers

Which organisms are typically diploid?

<p>Most animals (D)</p> Signup and view all the answers

What is an example of a contrivance in evolution?

<p>The evolution of mammal hair from reptilian scales (D)</p> Signup and view all the answers

What phenomenon can occur at the same locus in diploid individuals?

<p>Allelic dominance (C)</p> Signup and view all the answers

During meiosis, what occurs between homologous pairs?

<p>Genetic recombination (B)</p> Signup and view all the answers

What does the term 'Alternation of Generations' refer to?

<p>A life cycle that alternates between haploid and diploid generations (D)</p> Signup and view all the answers

What is the main idea of Cell Theory?

<p>All organisms are made of cells, and all cells arise from pre-existing cells. (B)</p> Signup and view all the answers

What ultimately drives the patterns seen in leaf size variations in trees?

<p>The evolutionary fitness of the trees resulting from selective forces. (D)</p> Signup and view all the answers

Which of the following best describes the concept of life being continuous?

<p>All cells arise from a single ancestral cell leading back through generations. (B)</p> Signup and view all the answers

What is an implication of the study of cell biology in understanding organisms?

<p>Understanding an organism involves comprehending how its cells function. (A)</p> Signup and view all the answers

In evolutionary terms, which statement about heritable traits is correct?

<p>Heritable traits that help individuals reproduce tend to become more common over time. (D)</p> Signup and view all the answers

What was a misconception about cell origin prior to Cell Theory?

<p>Cells arise from spontaneous generation under certain conditions. (B)</p> Signup and view all the answers

Which statement reflects a common misunderstanding about the connection between evolution and fitness?

<p>Not all evolutionary changes enhance an organism's fitness. (C)</p> Signup and view all the answers

What does Natural Selection primarily drive in evolutionary theory?

<p>The heritable change in populations over time grounded in environmental pressures. (C)</p> Signup and view all the answers

What is an exaptation?

<p>A trait that has evolved into a new function in descendants. (B)</p> Signup and view all the answers

Which of the following best describes the relationship between exaptations and contrivances?

<p>One cannot exist without the other. (B)</p> Signup and view all the answers

What distinguishes a vestigial trait from an atavism?

<p>Vestigial traits are present in all members of a species. (B)</p> Signup and view all the answers

Which term describes similarities in traits due to inheritance from a common ancestor?

<p>Homology (D)</p> Signup and view all the answers

How can a trait evolve from a contrivance to an exaptation over time?

<p>It must serve a new function in a different environment. (A)</p> Signup and view all the answers

What characteristic is common in traits exhibiting homoplasy?

<p>They are caused by convergent evolution. (B)</p> Signup and view all the answers

Why might modern reptiles still possess scales despite the evolution of feathers in birds?

<p>Scales can offer adaptive advantages in different environments. (C)</p> Signup and view all the answers

What is the primary distinction between homology and homoplasy?

<p>Homology involves traits derived from common ancestors, while homoplasy does not. (C)</p> Signup and view all the answers

What does Mendel's Law of Independent Assortment state?

<p>Traits sort independently from each other. (B)</p> Signup and view all the answers

In a dihybrid cross involving Round (R), Yellow (Y) and Wrinkled (r), Green (y) peas, how many possible phenotypes are typically observed?

<p>4 (B)</p> Signup and view all the answers

What was the purpose of a Test Cross in Mendelian genetics?

<p>To identify the genotype of an individual displaying a dominant trait. (D)</p> Signup and view all the answers

What is the expected phenotype ratio in the F2 generation of a monohybrid cross producing Round and Wrinkled peas?

<p>3 Round: 1 Wrinkled (D)</p> Signup and view all the answers

Which statement is true regarding genes located on the same chromosome?

<p>They cannot assort independently. (A)</p> Signup and view all the answers

What phenotype did Morgan observe when crossing a white-eyed male fruit fly with a red-eyed female?

<p>All offspring had red eyes. (D)</p> Signup and view all the answers

If an individual displays a dominant phenotype, how can its genotype be categorized?

<p>By conducting a Test Cross with a homozygous recessive individual. (C)</p> Signup and view all the answers

What is the significance of the reciprocal cross in Morgan's experiment?

<p>It helped confirm the results of the original cross. (C)</p> Signup and view all the answers

Flashcards

Cell Theory

All living organisms are made of cells, and all cells come from pre-existing cells.

Plasma Membrane

A thin, flexible barrier that surrounds a cell, regulating what enters and exits.

Emergent Properties

Properties that arise from the interaction of components within a system, where the whole is greater than the sum of its parts.

Evolutionary Theory

All life on Earth is the product of evolutionary processes, with heritable changes in populations over time.

Signup and view all the flashcards

Heritable Trait

A characteristic that is passed down from parents to offspring through genes.

Signup and view all the flashcards

Natural Selection

The process by which organisms with advantageous traits survive and reproduce more successfully, passing those traits to future generations.

Signup and view all the flashcards

Fitness

The ability of an organism to survive and reproduce in its environment.

Signup and view all the flashcards

Proximate vs. Ultimate Cause

Proximate causes are immediate, mechanistic explanations for a behavior or trait; Ultimate causes are evolutionary reasons for the trait or behavior.

Signup and view all the flashcards

Adaptation

A heritable trait that increases an individual's fitness in a particular environment.

Signup and view all the flashcards

Artificial Selection

The process where humans intentionally select for specific traits in organisms to breed, resulting in changes over generations.

Signup and view all the flashcards

What is the difference between natural selection and adaptation?

Natural selection is the process of selection for traits, while adaptation is a specific trait that increases fitness.

Signup and view all the flashcards

How does natural selection work?

Individuals with traits that make them better suited to their environment have a higher chance of surviving and reproducing, passing on those traits.

Signup and view all the flashcards

What are the 4 components of natural selection?

Variation, Inheritance, Selection and Time.

Signup and view all the flashcards

What is the purpose of artificial selection?

To create organisms with desirable traits for human needs.

Signup and view all the flashcards

Contrivance

A trait that evolved specifically for its current function.

Signup and view all the flashcards

Vestigial Trait

A trait that has lost its original function and is no longer used by the species.

Signup and view all the flashcards

Atavism

A trait that is present in a small number of individuals within a species, but is not present in the majority. It represents a trait that was present in the species' ancestors.

Signup and view all the flashcards

Homology

The similarity of traits between individuals due to shared ancestry.

Signup and view all the flashcards

Homoplasy

The similarity of traits between individuals that is not due to shared ancestry.

Signup and view all the flashcards

Convergent Evolution

The independent evolution of similar traits in different species that have adapted to similar environments.

Signup and view all the flashcards

Monohybrid Cross

A cross between two individuals that differ in only one trait, like a cross between a round pea and a wrinkled pea.

Signup and view all the flashcards

Dihybrid Cross

A cross between two individuals that differ in two traits, like a cross between a round, yellow pea and a wrinkled, green pea.

Signup and view all the flashcards

Mendel's Law of Independent Assortment

States that alleles for different traits are inherited independently of each other during gamete formation.

Signup and view all the flashcards

Test Cross

A cross between an individual with an unknown genotype (dominant phenotype) and a homozygous recessive individual to determine the genotype of the unknown individual.

Signup and view all the flashcards

Genotype

The genetic makeup of an individual, represented by the combination of alleles for a trait.

Signup and view all the flashcards

Phenotype

The observable physical or biochemical characteristics of an individual, determined by its genotype.

Signup and view all the flashcards

Homozygous

Having two identical alleles for a specific gene.

Signup and view all the flashcards

Heterozygous

Having two different alleles for a specific gene.

Signup and view all the flashcards

Exaptation (Pre-adaptation)

A trait that was adaptive in the past but serves a different function in descendants, providing the initial stage for a new adaptation.

Signup and view all the flashcards

Novel Adaptation

A completely new adaptation that doesn't resemble any ancestral traits, arising from a genetic mutation.

Signup and view all the flashcards

Imperfect Adaptation

An adaptation that, while beneficial, may not be the most efficient solution to an environmental problem. It's a compromise.

Signup and view all the flashcards

How do we recognize a novel adaptation?

A novel adaptation is identified when it significantly differs from ancestral traits, showcasing a unique, non-inherited feature.

Signup and view all the flashcards

What's the difference between adaptation and contrivance?

An adaptation is a general beneficial trait, while a contrivance is a modified version of an existing adaptation, evolved for a new purpose.

Signup and view all the flashcards

Why are many adaptations considered imperfect?

They represent compromises, evolved to solve current environmental problems, but may not be the most efficient or optimal strategy. They can be a product of historical constraints.

Signup and view all the flashcards

Chromosome

A structure in cells made of DNA and proteins, carrying genetic information. Different chromosomes within a set can have distinct shapes.

Signup and view all the flashcards

Ploidy

The number of chromosome sets in a cell. Haploid has one set (1n), diploid has two sets (2n).

Signup and view all the flashcards

Homologous Chromosomes

Pairs of chromosomes, one from each parent, containing the same genes but potentially different versions (alleles) of those genes.

Signup and view all the flashcards

Dominance

When one allele of a gene masks the expression of another allele in a diploid organism.

Signup and view all the flashcards

Meiosis

A cell division process that creates gametes (egg and sperm), halving the chromosome number and increasing genetic variation.

Signup and view all the flashcards

Haploid Gamete

A mature sex cell with half the number of chromosomes found in the parent organism.

Signup and view all the flashcards

Zygote

A single cell formed by the fusion of a haploid egg and a haploid sperm, containing the complete set of chromosomes.

Signup and view all the flashcards

Variation in meiosis

Meiosis increases variation through homologous chromosome pairing and exchange of genetic material (crossing over), and random assortment of chromosomes into gametes.

Signup and view all the flashcards

Study Notes

Science as a Process

  • Science involves identifying patterns and asking questions to understand those patterns
  • It focuses on disproving hypotheses to find true answers
  • A theory is a larger concept describing related phenomena

Theories and Hypotheses

  • Theories are supported by substantial evidence, while hypotheses are statements with less evidence
  • Scientific advancement builds on previous discoveries in a process of testing and refinement
  • A single experiment cannot prove a theory, but a single experiment can disprove it

Components of Scientific Theories

  • Theories have two main parts: Pattern and Process
  • Pattern describes repetitive observations within a system
  • Process describes the mechanism by which the pattern occurs

Unifying Themes in Biology

  • Cell Theory: All living organisms are made of cells, and all cells come from pre-existing cells
  • Evolutionary Theory: All life is the product of evolutionary processes, involving heritable changes in populations over time. Natural selection is the primary mechanism.

Biological Hierarchy

  • A hierarchical framework for organizing life
  • Starting with atoms, molecules, organelles up to biomes and the biosphere
  • Units at one level combine to form the next (e.g., organs form organ systems)
  • Focuses on emergent properties: collective properties greater than the sum of the parts at a lower level

Evidence for Evolution and Evolutionary Theory

  • Species are related and diverse
  • Species evolve over time (microevolution) and new species are created over long periods (Macroevolution)
  • Fossil record, geographic proximity of similar species, and homologous traits support evolutionary relationships
  • Species diversity and other observations indicate variation within species
  • Adaptations may be compromises due to conflicting selection pressures
  • Evolution is not always progressive toward a more complex or perfect form or adaptation
  • Adaptations are not always beneficial in all environments

Origin of Species & Darwin's Theory

  • Darwin's theory was influenced by his global observations
  • Variation, heredity, and natural selection are key components of evolution
  • Natural selection explains the development of species traits over time

Mechanisms of Inheritance & Variation

  • Genes are the primary unit of heredity
  • Mendelian experiments demonstrated that traits are passed down independent of one another
  • Genotype refers to the genetic makeup (genes) while phenotype refers to the observable traits
  • Differences in genotype can result in similar or different phenotypes
  • Sources of variation include mutations, gene segregation, DNA recombination during meiosis, and mutations
  • Variation among organisms is necessary for evolution, enabling the environment to select certain traits

Case Studies

  • Studies, like those related to fruit flies, help determine the inheritance patterns, sex determination, and the relationship between genes in a species.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Quiz Team

Related Documents

Bio 114 Exam 1 Notes PDF

Description

Explore the essential concepts of scientific processes, theories, and hypotheses. This quiz covers the relationship between theories and evidence, the components of scientific theories, and unifying themes in biology such as Cell Theory and Evolutionary Theory. Test your understanding of how science contributes to our knowledge of the natural world!

More Like This

Use Quizgecko on...
Browser
Open
Browser
Browser