Spring Biology DA Study Guide

Biome

• Biomes are large ecological areas on the Earth's surface, categorized by climate, geography, and the types of organisms that live there. Biomes are determined by the interaction of abiotic (non-living factors like climate and soil) and biotic (living factors like plants and animals) components in a specific region.

Adaptation

• Adaptations are heritable traits that enhance an organism's ability to survive and reproduce in its environment. They may include physiological changes, behavioral modifications, or structural features that allow species to cope with environmental stresses.

Theories of Evolution

Punctuated Equilibrium

• This hypothesis suggests that evolutionary development is characterized by isolated episodes of rapid speciation followed by long periods of stasis, where little evolutionary change occurs. For example, a species of marine animals might exist unchanged for thousands of years but suddenly adapt and diverge into a new species due to a significant environmental shift, like a change in sea level.

Stasis

• Stasis refers to a condition where evolutionary lineages remain relatively unchanged over extensive timescales.

Gradualism

• This theory posits that evolutionary change occurs slowly and gradually. For instance, the gradual increase in size and decrease in the number of leg bones in horses over millions of years exemplifies this concept. Gradualism implies that environmental conditions may shift slightly over long periods, inducing subtle changes in species.

Fossils

• Fossils provide critical evidence regarding the history of life on Earth. They showcase that organisms from the past are different from modern species, demonstrating a clear progression of evolution. Scientists utilize fossil dating and categorization to reconstruct timelines of when different organisms existed in relation to one another.

Examination of Evolutionary Change

1. Gradualism Indicators: Look for evidence of numerous slight changes in species over extended periods or minor environmental changes.

2. Punctuated Equilibrium Indicators: Look for evidence of few significant changes in a shorter timeframe or substantial changes to environmental conditions that spur rapid evolutionary shifts.

Genetic Drift and Natural Selection

• Punctuated Equilibrium is not an example of genetic drift but describes the rate of evolutionary changes which can stem from natural selection, genetic drift, or both. Similarly, Gradualism illustrates the relationship between gradual environmental changes and natural selection, rather than genetic drift.

Speciation

• Speciation involves the formation of new species, which can occur when gene pools of two populations become isolated. When populations evolve to the point that they can no longer interbreed and produce fertile offspring, new species emerge. Evolutionary pathways are influenced by natural selection, leading to reproductive isolation, which is fundamental in the speciation process.

Coevolution

• Coevolution occurs when two or more species influence each other's evolutionary paths due to close ecological interactions. This phenomenon is common in relationships such as predator-prey dynamics and symbiosis. For instance, the evolution of pesticide resistance in pests or the adaptation of hummingbirds' beak shapes and lengths to match the shapes of flowering plants exemplifies coevolution.

• The term "Coevolution" can be remembered as "do together."

Examples of Resistance

• Antibiotic Resistance: Bacteria develop resistance due to environmental pressures from antibiotic treatment, with resistant strains passing on the trait to offspring. Factors contributing to antibiotic resistance include over-prescribing, incomplete treatment courses, and poor sanitation practices. Notable resistant strains include MRSA and multidrug-resistant tuberculosis.

• Pesticide Resistance: Driven by natural selection, pest populations can develop heritable resistance to insecticides, particularly when the application is mismanaged or overused. For example, the fire blight bacterium has shown resistance to streptomycin, while apples have faced benomyl resistance.

• Drug-Resistant Viruses: Mutations in virus genes allow them to evade antiviral treatments. Overuse and misuse of antiviral drugs lead to the emergence of resistant strains, such as those seen in herpes, HIV, and influenza A and B.

Convergent and Divergent Evolution

Convergent Evolution

• This process describes how organisms from different evolutionary backgrounds develop similar traits due to adaptations to analogous environments or ecological niches. The flight mechanisms in insects, birds, pterosaurs, and bats are excellent examples of convergent evolution, where similar functions arise from different ancestral origins. This can be remembered as "come together."

Divergent Evolution

• Divergent evolution occurs when species from a common ancestor evolve different traits and become increasingly distinct, often in response to varying environmental conditions. An example is the diversity in vertebrate structure, including mammals and birds, stemming from shared ancestral traits. This can be visualized with homologous structures, which display similar origins but serve different functions. Remember this as "move apart."

Adaptive Radiation

• Adaptive radiation is a rapid diversification of a lineage from a common ancestor into various niches, particularly following significant environmental changes that create new opportunities or challenges. An example is the evolution of Darwin’s finches, which adapted to exploit different food sources following the geological changes in the Galapagos Islands.

Taxonomy and Classification

Importance of Classification

• Classification systems help organize biodiversity, making it easier to study and understand organism relationships. Phylogeny involves recognizing evolutionary relationships among organisms, moving beyond simple physical characteristics.

Cladograms

• Cladograms visually represent evolutionary relationships, where lines indicate evolutionary time and nodes represent common ancestors. The positioning and length of lines inform how closely related an organism is to others within the tree. This emphasizes that only the lines and nodes are critical, regardless of the diagram’s orientation. Understanding these relationships allows scientists to trace back the ancestry and evolutionary history of various species, highlighting their connections throughout time.

In cats, the bones in the legs involved in walking are very similar to bones in whale's flippers that are involved in swimming. Although they have different functions, these bones, called homologus structures, lead us to the theory that cats and whales _________.
a. Lived in the same time period
b. Have a common ancestor
c. Are both great swimmers
d. Have analogous structures to begin with

Have a common ancestor

Looking through the fossil record, there are times when numerous fossils look to just appear all at the same time, with similar characteristics. What is a good explanation for this?
a. A change in the environment occurred, and animals chose to express different traits.
b. New species are always just occurring, and there is no reason for it.
c. Ancient man killed off all the animals, and they raised new animals, which are then found in fossil record.
d. A change in the environment caused different genetic traits to allow for a greater chance for survival, and the fossil record shows this.

A change in the environment caused different genetic traits to allow for a greater chance for survival, and the fossil record shows this.

The total number of different alleles present in a population make up a _________.
a. Genotype
b. Phenotype
c. Gene pool
d. Gene flow

Gene pool

Heritable structures or behaviors that an organism possesses that allow it to more efficiently use its environment are _________.
a. Acclamations
b. Adaptations
c. Variations
d. Mutations

Adaptations

Which part of Darwin's theory of natural selection can be used to describe the following predator/prey relationship?
"When eagle prey on mice, some mice are killed and some escape"
a. Directional selection
b. Vestigial selection
c. Survival of the fittest
d. Homologous structures

Survival of the fittest

Birds and bees both have wings obviously. However it is also obvious that they did not evolve from a common ancestor. Which type of evolution would this be considered.
a. Convergent evolution
b. Divergent evolution
c. Simultaneous evolution
d. Flappy wing evolution

Convergent evolution

Old world monkeys would be found in which of the following countries?
a. Brazil
b. Canada
c. United Kingdom
d. The Democratic republic of Congo (African Countries)

The Democratic republic of Congo (African Countries)

Structures that no longer seam to have a particular use-like the Human appendix - in an animal are known as _________.
a. Homologous structures
b. Analogous structures
c. Vestigial structures
d. Physiological structures

Vestigial structures

For generations dogs have been bred and interbred by humans in order to acquire specific traits that we find desirable. This is an example of _________.
a. Natural selection
b. Artificial selection
c. Adaptations
d. Mutations

Artificial selection

Some forms of cephalopods are able to change the shape of their skin in order to resemble more threatening animals in their ecosystem. This is an example of _________.
a. Camouflage
b. Physiological adaptaion
c. Analogous structures
d. Mimicry

Mimicry

When the population becomes isolated, members of that breed must begin to interbreed in order to survive. Recessive traits may begin to show up more frequently than in outside populations. This phenomena is known as _________.
a. Gene flow
b. Gene drift
c. Mutations
d. Speciation

Speciation

Which type of adaptation happens quickly in bacteria populations that are antibiotic resistant?
a. Structural adaptation
b. Physical adaptation
c. Physiological adaptation
d. Phenotypic adaptation

Physiological adaptation

We have an expert-written solution to this problem!

Which of the following is a true statement about evolution?
a. Individuals evolve more slowly than populations
b. Individuals evolve, populations don't
c. Evolution happens rapidly on Earth
d. Populations evolve, individuals don't.

Populations evolve, individuals don't.

Briefly describe the process of Evolution by natural selection.

The best suited to their environment will be able to find mates and pass their adaptations to their offspring.

Who is known as the father of Evolution?

Charles Darwin

Where did Darwin go to establish his theories on evolution by natural selection?

The Galapagos Islands

Mastered (1)

You've been getting these terms right!

Select this one

Likeness in structure between parts of different organisms which are evidence of common ancestry are called _________.
a. Phylogenies
b. Anologies
c. Geneologies
d. Homologies

What is biotechnology?
The use of living organisms and biological systems to develop products or processes.

DNA Fingerprints

Which suspect matches the scene?
Answer depends on the fingerprint data provided.

Who is the father of the child?
Answer depends on the fingerprint data provided.

Which species is closely related?
Answer depends on the fingerprint data provided.

What is recombinant DNA?
DNA created by combining genes from different organisms.

Brief Descriptions and Economic Impact:

• DNA Fingerprinting: Identifies individuals using DNA; helps solve crimes.

• Recombinant DNA: Combines genes; used in medicine and agriculture.

• Gene Therapy: Corrects defective genes; can treat genetic disorders.

• Stem Cell Therapy: Uses stem cells to treat diseases.

• Cloning: Creating identical organisms; used in research.

• GMOs: Genetically modified organisms; used to improve crops.

Darwin vs. Lamarck

• Darwin: Natural selection, populations change.

• Lamarck: Inheritance of acquired traits, individuals change.

Genetic Variation (Peppered Moths)
Genetic variation helps some organisms survive better in changing environments, like dark moths blending in with soot-covered trees.

Darwin’s Theory of Natural Selection
Populations change over time due to natural selection.

Evolution Vocabulary

1. Homologous Structures: Same bones in different animals, showing a common ancestor.

2. Genetic Differences: Humans and chickens have different genes.

3. Adaptations: Honey possums and butterflies have different tongues.

4. Embryonic Similarity: Animals have similar embryos.

5. Antibiotic Resistance: Bacteria evolve to resist antibiotics.

6. Fossils: Remains of ancient organisms.

Comparative Anatomy

Bat and Bird:

• Evolution: Convergent Evolution

• Structure: Analogous

• Common Ancestor: No

Antibiotic Resistance
Bacteria survive antibiotics, reproduce, and spread. This is why the flu vaccine needs updating.

Virus: Living or Non-living?
Non-living; requires a host cell to reproduce.

How does a virus infect cells?
It attaches to a cell, injects its DNA, and takes over the cell.

Biodiversity & Challenges

Polar Bear Adaptations:

• Thick fur, large paws, white color.
  Challenges: Losing ice habitats due to climate change.

Other Biome:
In the desert, polar bear adaptations (like thick fur) wouldn't work.

Fossils

How are fossils formed?
By burial and mineral replacement of organic material.

What do fossils tell us?
They show evidence of past life and evolution.

Evolution Concepts

Adaptive Radiation:
One species evolves into many to fit different environments (e.g., Darwin’s finches).

Gradualism:
Slow, steady changes over time.

Punctuated Equilibrium:
Rapid changes followed by long periods of stability.