1
Q
Taxonomy
A
- Practice of classifying living things
- A.K.A Naming stuff
- The sciene of classification according to the inferred (presumed) relationships among organism
2
Q
Binomial Naming System
A
- Two part
- Scientific Name
- Usually italicized
- The first part is the genus, the second part is the species
- Always written, Genus Species
3
Q
Aristotle’s Classification System
A
- Early classification system
- Organisms were put into TWO groups: PLANTS & ANIMALS
- Each group was called a kingdom: KINGDOM PLANTAE & KINGDOM ANIMALIA
- Animals were further classified based on size, how they moved, if they were in water, air, etc.
- Plants were split into THREE categories based on their stems
- This system worked until the invention of microscopes
- Some microorganisms had characteristics like animals, some like plants, and some did not fit nicely into any category.
4
Q
Protista (A.K.A Protists)
A
- Unicellular or multicellular
- Eukayotic
- Some photosynthesize and some DO NOT
- Some are decomposers that obtain nutrients by decomposing and then absorbing their food
- Some ingest food
- Ex. Algae, amoeba
4
Q
Ernst Hackle’s Classification System
A
- Improved on Aristotle’s system by classifying microorganisms that were neither animals nor plants in a THIRD kingdom called PROTISTA
- Created the THREE KINGDOM CLASSIFICATION SYSTEM:
- Protista
- Plantae
- Animalia
5
Q
Six kingdoms of Life
A
- Six Kingdoms:
1. Archaea (or Archaebacteria):- Single-celled organisms that lack a nucleus. Live in extreme environments
- Bacteria ( or Eubacteria):
- Single-celled organisms that lack a nucleus
- Protista
- Fungi
- Plantae
- Animalia
- [3,4,5,6] Unicellular or multicellular organisms. Have cells that have nuclei. Called eukaryotes
- Single-celled organisms that lack a nucleus. Live in extreme environments
6
Q
Fungi
A
- Secret digestive enzymes onto their food source and then absorb the molecules that are released by the enzymes
- DO NOT move
- DO NOT have chloroplasts (Unable to photosynthesize)
- Can be multicellular or unicellular
- Ex. Mushrooms, mould
7
Q
Plantae
A
- An organism that photosynthesizes to make its own food
- Most do NOT move & multicellular
8
Q
Animalia
A
- Multicellular
- Heterotrophs
- Ingest their food
- Most are mobile
- Complex and specialized cells
9
Q
3 Domains of Life
A
- Levels of classification ABOVE the kingdom are called DOMAINS
- 3 domains: Bacteria, Eukarya, Archaea
10
Q
Linnaeus System
A
King –> Kingdom
Phillip –> Phylum
Came –> Class
Over –> Order
From –> Family
Great –> Genus
Spain –> Species
NOTE: If two species have the same Genus they are closely related.
11
Q
Dichotomous Key
A
- A method for determining the name of an organism
- Very helpful for identifying organisms with slight differences
- A two-part hey used to identify living things [Di = “two”]
- The key is constructed so that a series of choices must be made, and each choice leads to a new branch of the key. Until the name of the organism has been identified.
12
Q
Adaptations
A
A structural, behavioural or physiological process that helps an organism survive and reproduce in a particular environment [Occurs over many generations]
13
Q
Variations
A
- The visible or individual differences between individuals of the same species
- Variation in individuals can be an advantage or disadvantage, or have no effect on the individuals.
14
Q
Lamarck
Name of Theory and Explanation.
A
Created the theory “Inheritance of Acquired Characteristics”
- Felt species increased in complexity over time, until they achieved a level of perfection
- Felt characteristics that were acquired during an organism’s lifetime could be passed on to its offspring, called the inheritance of acquired characteristics.
- Initially, his ideas were believed but later rejected after biologists learned about cells, genes and heredity.
- Example:
- Giraffes were believed to have originally had a short neck. So they keep on stretching their neck to reach leaves higher on the tree. Until their necks progressively become longer. In which they can give that trait to their offspring.
15
Q
What was the name of Darwin’s Theory?
A
Darwin’ Theory was called the “Theory of Natural Selection”
16
Q
Mutations
A
- Random changes in the genetic material of an organism
- Happens continuously in the DNA of any living organism and can occur spontaneously
- When DNA is copied before a cell divides
- When DNA mutates, a cell can show new characteristics
- Mutations can lead to good or bad changes
17
Q
Theory of Natural Selection
A
- Earth species shows variation
- There is compettion within each species for food, living space, water, mates, etc.
- The “better adaptation” members of these species are more likely to survive- “survial of the fittest”
- These surviovrs will pass on their better genes to their offspring who will also show this beneficial variation.
- VARIATION –> COMPETITION –> ADAPTATION –> SELECTION
18
Q
Can Mutations Provide Selective Advantage?
A
- Yes, mutations can provide selective advantage.
- Mutations can be harmful, good or cause a disadvantage in one environment or an advantage in another environment.
- When a mutation is harmful in one environment but good in another environment, we say it provides “selective advantage” in the new environment
- Ex. Individuals with sickle-cell anemia may have a disadvantage in one environment, but when placed in an environment with high rates of malaria, they have a huge advantage.
19
Q
Natural Selection
A
- The resultof differential reproductive success of individuals caused by variations in their inherited characteristics.
- A process that results when the characteristics of a population of organisms change because individuals with certain inherited traits survive specific local environmental conditions
- For natural selection to occur, there must be a variety of diversity within a species
- Populations change, NOT individuals
- Natural selection doesn’t anticipate change in the environment instead, natural selection is situational
- A trait at one time may have no relevance to survival, but if the environment changes, the trait might now be advantageous
19
Q
5 Key Points About Natural Selection
A
Overproduction (More babies that can survive in the environment)
Competition
Varation- (Mutation)
Survival of the fittest (Most adapted)
Origin of New Species
20
Q
Further Evidence of Evolution
A
Fossil Records, Transitional Fossils, Anatomy, Patterns of Distribution, Embryology, Molecular Biology, Genetics, Artifical Selection, Natural Selection
21
Q
Fossil Records
A
- Shows the history of life by showing the species that were alive in the past
- Fossils found in young layers of rock (from recent times) are MORE similar to species that are alive today than fossils found in older, deeper rocks
- Fossils appear in chronological order to the rock layer, so probably ancestors to species can be found in older rocks.
- Not all organisms appear in the fossil records at the same time- the fossil record shows that fish are the oldest vertebrates, amphibians came later, reptiles came later, and mammals and birds came later than that
21
Q
What was the order species came to be according to fossil records?
A
- Reinforces the idea that amphibians evolved from ancestral fish, and reptiles evolved from ancestral amphibians; mammals and birds evolved from different groups of reptiles
- [Fish —> Amphibians —> Mammals —> Birds]
22
Transitional Fossils
- Original fossils showed gaps that led people to be skeptical of the idea of evolution
- Later, “transitional fossils” were discovered - these show intermediary links between groups of organisms
23
Biogeography
The study of the past and present geographical distribution of organism
24
Patterns of Distribution
Darwin and Wallace hypothesized that species evolved in one location and then spread out to other regions.
25
Evidence in Favour of Patterns of Distribution
- Geographically **close** environments are more likely to be populated by **related species** than locations that are geographically **separate** more similar
- Animals found on **islands** often closely resemble animals found on the **closest continent**
- Fossils of the same species can be found on the **coastline** of neighbouring continents
- Closely related species are almost **NEVER** found in exactly the same location or habitat
- Since it will be **TOO** much competition for resources
26
Anatomy
- Bone structure
- Many living creatures that look quite different on the surface have similarities underneath their skin that suggest that they are related to each other.
27
Homologous Structure
- Features with similar structures but different functions
- “Homo” = Same “~logous” = Information
- Structures that have similar structural elements and origin, but may have a different function
- They are similar because they came from a common ancestors
*** Ex. The limbs of a human, cats, whale and bats.**
28
Analogous Structure
- Features that are similar in appearance and function, but do not appear to have the same evolutionary origin
- Body parts that perform similar functions, even though the organisms do ***NOT*** have a common evolutionary origin
- Develop differently and have very different internal structures and embryonic development.
- Ex. Wings of a bird **AND** the fin of a penguin
29
Vestigial Structures
- Rudimentary structures with no useful function
- Body structures in animals that show gradual change over time. In some cases, these changes have reduced or removed the functions of some body parts and organs.
- Ex. The wings of penguins and the leg bones of snakes, and the wisdom tooth in humans
30
Embryology
- Stages of baby development
- Embryos of different organisms exhibit similar states of embryonic development
- Suggesting a common ancestry
- Embryos of different organisms that are closely related show very similar stages of embryonic development
31
Molecular Biology
- Evolutionary relationships among species are reflected in their DNA and proteins
- All cells are made of membranes filled with water, genetic material, proteins, lipids and carbs
- Proteins called enzymes control biochemical reactions in all organisms
- Proteins are synthesized from amino acids in all organisms
- All cells can replicate DNA in all organisms
- Scientists can determine how closely related two organisms are by comparing their DNA
32
Artificial Selection
Another word for plant and animal breeding, in which people breed individuals with desired characteristics in order to get offspring with those same characteristics
32
Fitness
An organism's reproductive success.
33
Convergent Evolution
- When one or more different species evolve similar characteristics due to a common environment
- Analogous structures
34
Divergent Evolution
- When an ancestral species diverges into many different species
- Homologous structures
35
Species
Organisms that are able to breed with one another to create the same fertile offspring.
36
Ways To Keep Populations Separate.
Geographical Barriers
Biological Barriers
37
Speciation
* The formation of new species and it can occur when two populations are prevented from interbreeding.
* If populations become isolated enough, speciation will eventually occur because of changes accumulated in populations due to natural selection, which affects reproduction.
38
Geographical Barriers
- Physically separate barriers
- Ex. Mountains, islands, lava flow, rivers
- The species **DO NOT** have to be isolated forever, but it does have to be maintained long enough for the species to become reproductively incompatible with the original population
38
Biological Barriers
- Keep species reproductively isolated even if their ranges overlap
- Examples:
- **Pheromones**: Chemical signals/ smells that are used to attract mates
- Different habitats within a common area
- **Behaviour**: Mating calls of birds are often different between species birds that have diverged from a common ancestor may have similar calls, but they are different
38
Allopatric Speciation
- Occurs as a result of ***physical barriers.***
- Speciation by reproductive isolation
- Most new species are believed to arise by a 3 step process called **allopatric speciation:**
1. A physical barrier separates a single interbreeding population into two or more groups that are isolated from each other.
- Any mutations that occur in one of these isolated groups are **NOT** shared with the other population
2. Natural Selection works in the separated groups ***independently***, resulting in **inherited differences** in the **TWO** populations.
- In other words, the populations evolve independently.
- Differences in selective pressures will be greater if the populations experience pronounced differences in their environments
3. In time, accumulated physical and/or behavioural differences between the populations become so pronounced that the groups, should they be reunited, would no longer be sexually compatible.
- At this point, they have from **TWO** or more distinct species
39
Transformation
- A new species may result from accumulated changes in the population over a long period of time
- A new species gradually develops as a result of mutations and adaptation to changing environmental conditions, and the old species is gradually replaced.
- If this was the only mechanism of speciation, the total number of species and diversity of species would NOT change over time
- Also called **phyletic speciation** or **anagenesis**
39
Sympatric Speciation
- It occurs as a result of a ***biological barrier***
- Occurs when there are **no physical barriers** preventing any members of a species from mating with each other.
- Members of the species remain close together
- The new species has some characteristics that make them prefer a certain aspect of the environment (such as food or shelter), keeping them from reproducing with other members of the species
40
Divergence
- One or more species arise from a parent species that continue to exist
- Increases biological diversity because it increases the number of species
- Also called **branching evolution** or **cladogenesis**
41
Adaptive Radiation
The diversification of a common ancestral species into a variety of species, all of which are differently adapted.
A rapid version of Cladogenesis.
42
Pace of Evolution
- Currently, two models exist for how fast evolutionary change is occurring:
1. Gradualism
2. Punctuated Equilibrium
43
Gradualism
- Gradual change occurs steadily in a linear fashion
- Big changes occur as a result of many small changes
- We don’t see this in the fossil records
44
Punctuated Equilibrium
- The fossil record generally shows species that appear suddenly and then disappear just as abruptly
- This shows periods of rapid change
- Punctuated equilibrium model proposes that evolutionary history consists of long periods of equilibrium where there is little change, “punctuated’ or interrupted by periods of speciation.
- According to this, most species undergo most of their morphological changes when they first diverge from the parent species. After that, the species change relatively little.
45
Natural Selection Summary Point:
1. Life forms have developed from ancestral species
2. All living things are related to one another by varying degrees through common descent
3. All living things on Earth have a common origin (share a common ancestor)
4. The mechanism by which one species evolves into another species involves random heritable genetic mutations.
- Some mutations result in a survival advantage for an individual.
- If so, the individual is more likely to survive and pass this mutation on to their offspring.
- Eventually, the successful mutation increases in the population and causes the population as a whole to start to change.
46
Why is a scientific name better than a common name?
- It is better to use a scientific name rather than a common name because scientific names are standardized across languages and countries, ensuring clarity in communication among scientists globally.
- It also avoids ambiguity, as common names can vary regionally, leading to confusion.
- Ex. A “jellyfish” can refer to multiple species, but the scientific name is specific, so it is easier to distinguish between them.
- The scientific name also provides insight into the organism’s biological characteristics and relationships with other species.
- Scientific names remain stable over time due to the majority of the names are Latin, which is a dead language. Unlike common names, which can change with cultural shift or new discoveries.
47
Does Variation Always Lead to Adaptation?
Variation does not always lead to adaptation because variation is the raw material for adaptation, but only beneficial variations that are selected for by the environment can lead to adaptations.
48
Why Does Variation Occur?
Variation occurs because of the random nature of genetic processes and interactions, and it's essential for evolution and the survival of species in changing environments.
Bio 20-1 AP
flashcards
Decks in class (14)
# Cards
-
Digestion Quiz92
-
Circulatory Systems Quiz90
-
Respiratory & Excretory Quiz85
-
Muscles15
-
Human System Review-Bio 20-1 AP283
-
Respiratory & Excretory Quiz 2.087
-
Biosphere Quiz- Cycle52
-
Biosphere Unit Test97
-
Ecology64
-
Evolution Quiz55
-
Ecology & Evolution Unit Quiz119
-
Photosynthesis Quiz39
-
Cellular Respiration Quiz20
-
Fertilization & Pregnancy & Labour29
