Unit 3 Flashcards
Explain how global climate differences and biotic factors impacts species distributions across the planet.
Global climate differences and biotic factors, such as the plants and animals in a given ecosystem, can impact the distribution of species across the planet. Climate refers to the average weather conditions in a region, including factors such as temperature, precipitation, and humidity. Biotic factors refer to the living organisms and interactions between them in an ecosystem. These factors can affect where species are able to live and thrive, and can ultimately determine their distribution across the planet.
Explain how temperature and precipitation drive global species distributions.
Temperature and precipitation drive global species distributions by determining the types of habitats that are suitable for different species. These two factors, along with other factors like biotic interactions and geography, can influence where different species can live and thrive, ultimately determining their distribution across the planet.
Describe the latitudinal diversity gradient.
The latitudinal diversity gradient is a pattern in which the diversity of species, or the number of different species in a particular area, decreases as latitude increases from the equator to the poles. This pattern is observed across many different taxonomic groups, including plants, animals, and microorganisms.
What are the 4 hypothesis of the latitudinal diversity gradient?
1.The environmental variability hypothesis, which suggests that higher environmental variability at the equator leads to higher species diversity.
2.The energy hypothesis, which suggests that higher levels of solar energy at the equator lead to higher productivity and species diversity.
3.The area hypothesis, which suggests that the larger land area and longer coastline at the equator provides more habitat for species, leading to higher species diversity.
4.The evolutionary hypothesis, which suggests that the equator has been a center of evolution for longer periods of time, allowing for the development of a greater diversity of species.
Define historical biogeography
Historical biogeography is the study of how species have moved and adapted over time, and how the Earth’s geography and climate have changed and influenced their distribution.
How has time impacted species distributions?
Over time, the Earth’s geography and climate have changed, leading to changes in the distribution of species. For example, the movements of the Earth’s continents, changes in sea level, and the emergence and extinction of land bridges have all influenced the distribution of species. Additionally, climate change has caused shifts in the distribution of species, with some species moving to new areas to find suitable conditions and others becoming extinct as their habitats have changed. Overall, time has had a major impact on species distributions, and the study of this impact is a key focus of historical biogeography.
How does size of a region impact species diversity?
Larger regions tend to have higher species diversity than smaller regions. This is because larger regions provide more habitat for species to occupy, allowing for a greater number of different species to coexist. Additionally, larger regions are more likely to have a greater range of environmental conditions, providing opportunities for a wider variety of species to adapt and thrive.
Why do we see the species-area relationship?
The species-area relationship is thought to arise because larger areas provide more habitat for species to occupy, allowing for a greater number of different species to coexist. Additionally, larger areas are more likely to have a greater range of environmental conditions, providing opportunities for a wider variety of species to adapt and thrive.
How does island size impact extinction rate?
Island size can have a major impact on the extinction rate of species, with smaller islands tending to have higher rates of extinction. This relationship is important for the conservation of island species and the management of island ecosystems.
How does distance from a mainland impact immigration rate?
Distance from the mainland can have a major impact on the immigration rate of species to an island, with closer islands tending to have higher rates of immigration. This relationship is important for understanding the dynamics of island ecosystems and the colonization of islands by species.
What is the equilibrium theory of island biogeography?
The equilibrium theory of island biogeography is a theory that explains the dynamics of species diversity on islands. This theory proposes that the number of species on an island is in a state of equilibrium, or balance, between two opposing processes: immigration of new species to the island and extinction of existing species on the island.
The equilibrium theory predicts that, over time, the number of species on an island will approach a equilibrium value, where the rates of immigration and extinction are equal. This equilibrium value will depend on the particular characteristics of the island, such as its distance from the mainland, its area, and the level of habitat disturbance.
When did life originate on Earth?
~3.5 billion years ago
How old is the Earth?
~4.5 billion years old
How and where did life originate?
The warm little pond hypothesis and the deep-sea hydrothermal vent hypothesis, among others.
What were the four key developments of the Precambrian?
The Precambrian period is the earliest part of Earth’s history, spanning from the formation of the planet about 4.6 billion years ago to the beginning of the Cambrian period about 541 million years ago. The four key developments of the Precambrian include:
1. The formation of the Earth
2. The emergence of the first life forms
3. The development of the atmosphere and oceans
4. The formation of the first continents.
Where did the oxygen in our atmosphere originate?
The oxygen in Earth’s atmosphere originated from the photosynthesis of early life forms, such as cyanobacteria. These organisms, also known as blue-green algae, are thought to have emerged about 3.5 billion years ago. They used energy from the sun to convert carbon dioxide and water into organic compounds and oxygen, releasing the oxygen into the atmosphere
What are the three domains of life?
Archaea, Bacteria, Eukarya
What is Archaea?
Single-celled microorganisms
Distinguished from other forms of life by their unique biochemical and genetic characteristics.
Found in a variety of extreme environments, such as hot springs, deep-sea vents, and saline lakes.
When did Archaea originate?
Originated about 4 billion years ago
What is Bacteria?
Single-celled microorganisms
Distinguished from other forms of life by their lack of a cell nucleus and other membrane-bound organelles
Found in nearly every environment on Earth.
When did Bacteria originate?
Originated about 3.5 billion years ago
What is Eukarya?
The Eukarya are a group of organisms that are distinguished from other forms of life by the presence of a nucleus and other membrane-bound organelles in their cells.
They include a diverse array of organisms, such as plants, animals, and fungi.
Are typically larger and more complex than the other two domains.
When did Eukarya originate?
Originated about 1.6 billion years ago
How do prokaryotes and eukaryotes differ in terms of their cellular structure
Prokaryotes and eukaryotes are the two main categories of living organisms.
Prokaryotes are single-celled organisms that lack a defined nucleus and other membrane-bound organelles
Eukaryotes are typically larger and more complex, and have a defined nucleus and other membrane-bound organelles
One main difference:
The structure of their cells
With prokaryotic cells being simpler and smaller, and eukaryotic cells being more complex and larger.
How do bacteria and archaea acquire energy?
Bacteria and archaea are single-celled organisms that obtain energy in a variety of ways, including photosynthesis, chemosynthesis, and the consumption of other organisms or organic matter.
What are extremophiles?
Extremophiles are microorganisms that can survive in extreme environments, such as extreme temperatures, high levels of acidity or alkalinity, or high levels of radiation.
why do we study extremophiles?
Studying extremophiles can provide insights into the origins and evolution of life, as well as potential applications in biotechnology and other industries.
Differentiate between bacteria and archaea
Genetic makeup:
Bacteria has a circular piece of DNA
Archaea have a linear or a complex genome structure
Cell structure:
Bacteria has a cell wall
Archaea lacks a cell wall
Metabolic pathways:
Bacteria using a variety of metabolic pathways to obtain energy
While archaea primarily use methanogenesis or methanotrophy.
Habitats:
Bacteria being more common in aqueous environments
Archaea are found in extreme environments such as hot springs and deep-sea vents.
Distinguish between the two bacterial cell wall types
Gram-positive bacteria have a thick cell wall composed of peptidoglycan.
Gram-negative bacteria have a thin cell wall composed of lipopolysaccharides and peptidoglycan.
The two bacterial cell wall and their implication for pathology
Gram-positive bacteria are generally less resistant to antibiotics and other antimicrobial agents, and are often more susceptible to infections.
Gram-negative bacteria are generally more resistant to antibiotics and other antimicrobial agents, and can be more difficult to treat.
Define viruses
A virus is a tiny infectious particle that is made up of genetic material surrounded by a protein coat. It can only reproduce inside the cells of other organisms.
Why are viruses not considered organisms?
Viruses are not considered organisms because they are not capable of independent reproduction. Additionally, viruses lack many of the other characteristics that are commonly associated with living organisms, such as the ability to respond to stimuli, grow, and evolve.
What are the two common morphologies of viruses?
Spherical and Filamentous.
Spherical viruses are roughly spherical in shape, while filamentous viruses are long and cylindrical.
What are the requirements of life – do viruses meet these requirements?
The requirements of life:
Ability to grow (Viruses lack)
Ability to reproduce (Viruses lack)
Ability to maintain homeostasis (Viruses lack)
Ability to respond to stimuli (Viruses lack)
Ability to evolve (Viruses lack)
Describe how diverse viruses are with respect to disease.
Viruses are incredibly diverse and can cause a wide range of diseases in humans and other animals. This diversity means that viruses can affect many different parts of the body and cause a wide range of symptoms. Because of their diversity, viruses can be difficult to prevent and treat. Additionally, some viruses are able to mutate rapidly, which can make them even more difficult to control.
How do biologists use phylogenetic trees to study viruses?
Biologists use phylogenetic trees that show the relationships between the viruses and help them understand how viruses are spread and how they evolve.
How are viruses classified?
Viruses are classified based on their shape, their size, and the type of disease they cause.
Why is viral evolution so fast?
Viral evolution is fast because viruses have a high rate of mutation and can reproduce quickly. This allows them to adapt to new environments and develop resistance to antiviral drugs more quickly than other types of organisms.
Differentiate eukaryotes from prokaryotes and archaea.
Eukaryotes are a type of organism that contains cells with a defined nucleus and other membrane-bound organelles. This group includes animals, plants, and fungi, as well as some single-celled organisms.
Prokaryotes are a group of organisms that lack a defined nucleus and other membrane-bound organelles. This group includes bacteria and archaea.
Archaea have a unique type of cell wall that is not found in prokaryotes.
What are the four fundamental features shared by all eukarya?
- A defined nucleus that contains the cell’s genetic material.
- Membrane-bound organelles, such as the mitochondria and the endoplasmic reticulum.
- A cytoskeleton that provides support and structure to the cell.
- The ability to perform cell division through a process called mitosis.
How has the nucleus evolved?
The nucleus evolved to protect and organize the cell’s genetic material. It originated when a prokaryotic cell engulfed another prokaryotic cell and the two cells began to live together. The engulfed cell eventually evolved into the nucleus.
How has the mitochondria evolved?
The mitochondria evolved from ancient bacteria that were engulfed by a host cell. Over time, the engulfed bacteria and the host cell formed a symbiotic relationship, leading to the evolution of the mitochondria.
How has the chloroplast evolved?
The chloroplast is thought to have evolved from ancient cyanobacteria that were engulfed by a larger prokaryotic cell. This engulfed bacteria eventually formed a symbiotic relationship with the host cell, leading to the evolution of the chloroplast.
What evidence supports the origination of mitochondria by endosymbiosis?
The evidence that supports the origination of mitochondria by endosymbiosis includes the presence of their own genetic material and the similarity of their genes to those of bacteria.
What is primary endosymbiosis?
Primary endosymbiosis is the process by which a prokaryotic cell is engulfed by another prokaryotic cell, leading to the formation of a symbiotic relationship between the two cells.
This is thought to be the event that gave rise to the first eukaryotic cells.
What is secondary endosymbiosis?
Secondary endosymbiosis is the process by which a eukaryotic cell is engulfed by another eukaryotic cell, leading to the formation of a symbiotic relationship between the two cells.
This is thought to be how organelles such as mitochondria and chloroplasts were formed.
What is the difference between secondary and primary endosymbiosis?
- Primary endosymbiosis involves the engulfment of a prokaryotic cell by another prokaryotic cell, while secondary endosymbiosis involves the engulfment of a eukaryotic cell by another eukaryotic cell.
- Primary endosymbiosis is thought to have given rise to the first eukaryotic cells, while secondary endosymbiosis is thought to have led to the formation of organelles such as mitochondria and chloroplasts.
- Primary endosymbiosis is a one-time event that occurred in the distant past, while secondary endosymbiosis can continue to occur in some organisms.
What organisms have chloroplasts that originated from secondary endosymbiosis?
Plants and Algae
What organisms have chloroplasts that originated from primary endosymbiosis?
How can we distinguish between these processes by examining the membranes of chloroplasts?
What evidence supports the origination of the nuclear envelope by infolding?
What is a protist?
Explain why protists are paraphyletic.
Where are protists most commonly found?
What is the difference between single celled and multicellular life cycles?
Be able to label the steps of different life cycles.
How do protists move?
How do protists acquire energy?
What is malaria? What type of organism causes malaria?
