2nd S emester Flashcards
The number and the kinds of organisms living on Earth at a particular time is called?
biological diversity
The _ is the scientific explanation of the diversity of life.
evolutionary theory
_, or change over time, is the process of how present-day organisms have descended from ancient ones.
Evolution
A _ is a well-supported, testable explanation of a natural phenomenon.
theory
A key factor for an organism to thrive and reproduce depends on how well-suited the organism is to the environment.
Natural Selection
The ability of an individual to survive and reproduce in a specific environment is called its?
fitness
The concept of fitness is the central process of evolution by _.
natural selection
Species descend through generations with several changes over time. This principle also implies that organisms are related to one another.
Descent with modification
The principle of evolution that states that all organisms share common ancestry.
Common descent
3 types of natural selection that can affect populations:
Directional selection
Stabilizing selection
Disruptive selection
_ happens when a change in the environment causes a change in the observable spectrum of phenotypes.
In this process, organisms with a phenotype that is well-suited to their current environment are more likely to survive.
Directional selection
_ occurs when intermediate phenotypes are more likely to survive in the environment.
Stabilizing selection
_ occurs when extreme phenotypes are more likely to adapt to the environment.
Disruptive or diversifying selection
In _, nature provides the variation among different organisms so that humans can select the variations that are useful to them.
artificial selection
Artificial selection can be done through a technique called _. This type of mechanism is done by farmers and breeders.
In this process, individuals with desirable traits or characteristics are bred to increase the chances of having offspring with the same desirable traits.
selective breeding
_ also contributes to the population change from one generatin tho the net. This is described as the selected probability of mating with another individual in the population.
Nonrandom mating
_ is when individuals are more likely to mate with their close relatives thai mith distant relatives. In this manner, individuals choose their mates based on their genetic history.
Inbreeding
Inbreeding may lower the population’s ability to survive and reproduce, a condition called _.
inbreeding depression
_, or assortative mating, happens when individuals select distant relatives than close relatives as their partners. In this type of breeding, individuals with similar phenotypes are more likely to mate.
Outbreeding
_ is caused by unpredictable changes in allele frequencies due to small population sizes. Thus, a certain allele can be passed on to numerous offspring by chance.
Genetic drift
2 examples of random genetic drifts that can have significant effects in small populations:
Population bottleneck
Founder effect
_ occurs when a sudden sharp decline in the population (usually from natural disasters such as volcanic activities and strong weather disturbances) results in a drastic reduction of the total genetic diversity of the original population.
Population bottleneck
The _ happens when there is a loss of genetic variation because of the migration of a small subgroup in a population.
founder effect
_ is the change in the structure of a gene caused by alterations in the DNA sequence of an organism.
Mutation
4 types of Mutation
Substitution
Insertion
Deletion
Frameshift
This occurs when the genetic codon has one altered nitrogenous base.
Substitution
Substitution may cause a _, wherein an altered nitrogenous base still produces a codon that encodes for the same amino acid.
silent mutation
_ is characterized by the addition of an extra set of base pairs to the genetic material.
Insertion
_ occurs when a set of base pairs in the genetic material is omitted.
Deletion
Insertions and deletions in the genetic material cause another type of mutation known as _. This happens when the information is no longer parsed correctly, resulting in the production of useless proteins.
frameshift
Mutation may be either _ or _.
neutral or beneficial
A _ affects the organism’s phenotype but has no impact on its survival or reproduction.
neutral mutation
_ affects the phenotype of organisms, resulting in an increase in their chances of survival or reproduction.
Beneficial mutation
_ is simply a rearrangement of genes. This process naturally occurs during the crossing over stage in meiosis, where there is an exchange of DNA between homologous chromosomes.
Recombination
Gene flow is also known as _.
migration
_ happens when there is transfer of genes from the gene pool of one population to another.
Gene pool/migration
Two types of migration
Emigration
Immigration
_ happens when organisms leave their habitat.
Emigration
_ happens when organisms enter another habitat and live in it.
Immigration
The earliest example of evolution did not start with Charles Darwin. It was in the _ that many naturalists began to state the idea that life might not have been fixed since creation.
18th century
17th Century
John Ray (1627-1705)
He established the modern concept of species noting that one of the members of one species do not interbreed with members of another species.
He first used the term species as the basic unit of taxonomy.
He also studied fossils and recognized them as remnants of organisms that were once alive.
John Ray (1627-1705)
Scientists in 18th Century
Carl Linnaeus (1707–1778)
Georges Louis Leclerc Comte de Buffon (1707–1788)
Erasmus Darwin (1731–1801)
Georges Cuvier (1769–1832)
Jean-Baptiste Lamarck (1744–1829)
James Hutton (1726–1797)
Charles Lyell (1797–1875)
Charles Robert Darwin (1809–1882)
Alfred Russel Wallace (1823–1913)
He developed the modern taxonomic system that is still used today.
Carl Linnaeus, also called Carolus Linnaeus) 1707-1778)
He wrote a 36-volume Histoire Naturelle) Natural History series.
He contributed to the debate on the age of Earth, suggesting that our planet had initially formed in a molten state and that its gradual cooling must have taken far longer than 70 000 years.
He also considered the role of vestigial organs, creating a possibility of species descending from earlier organisms.
Georges Louis Leclere, Comte de Buffon (1707-1788)
He was Charles Darwin’s grandfather.
He was aware that the modern organisms are different from the fossils scientists have collected.
He believed that the offspring inherited features.from their parents, and that the organisms today descended from a common ancestor.
Erasmus Darwin (1731-1802)
He studied and wrote books on comparative anatomy, which were extremely useful in interpreting the remains of fossils.
He classified animals based on their body plans. This classification eventually became important in analyzing relationships among organisms.
His studies about fossils contributed and gave rise to the science of paleontology. Finally, he recognized that particular groups of fossil organisms were associated with certain rock strata.
Georges Cuvier (1769-1832)
He proposed the theory of use and disuse, which stated that organisms develop their traits due to the frequent use of such.
He also proposed that those traits may be passed on to their offspring.
Jean-Baptiste Lamarck (1744-1829)
He made a signifient contrihution in the understanding of the geological processes that shaped Earth.
He recognized that Earth is extremely old (more than millions of years) and no need for global catstrophes to shape Esrth.
He was the proponent of UNIFORMITARIANISM, which states that present geological features of Earth are results of gradual processes such as erosion and sedimentation.
It was through Hutton that Darwin was able to adapt the principles of ggradual change to his model of how speicies evolved.
James Hutton (1726-1797)
He considered the shaping of Earth’s surface as a result of gradual
long-term natural changes.
He also collected many pieces of evidence to support the principle of uniformitarianism and wrote about them in his book PRINCIPLES OF GEOLOGY, which was also influential to the creation of Darwin theory.
Charles Lyell (1797-1875)
He came up with the idea that the best-adapted organisms are those that can survive to breed and pass on their traits to their offspring.
One of his highlighted contributions was the development of his
theory of evolution by natural selection as a coherent explanation for the form and distribution of species in different locations.
Charles Robert Darwin
(1809-1882)
Although he made an independent study on the origin of organisms, _ arrived at the same conclusion as Darwin’s: that organisms with favorable traits are those that carry on to the next generation.
Thus, Wallace had contributed to some of the postulates of Darwin’s theory of evolution.
Alfred Russel Wallace (1823-1913)
_ contributed significant ideas on our current understanding of evolution.
Charles Robert Darwin
Charles Robert Darwin was born in England on _.
12 February 1809
In 1831, Darwin went aboard the _ in its voyage around the world.
H.M.S. Beagle
His most famous travel involved a trip to the _, composed of many small islands located 1 000 kilometers (km) west of South America.
Galapagos Islands
Darwin wrote and published a book entitled _, in which he proposed the now famous theory of evolution by natural selection.
On the Origin of Species
With the help of what he
learned from _, an English economist, Darwin realized that high birth rates
and a shortage of life’s basic needs would eventually force organisms into competition for resources.
Thomas Malthus
Aside from Charles Darwin, _, French naturalist, was one of the first scientists to recognize that living things have changed over time.
He proposed that all species descended from other species.
Jean-Baptiste Lamarck
In _, Lamarck published his theory of how organisms changéd over time. His main ideas included that through selective use or die of organs, organisms may acquire or lose certain traits during their lifetime. Additionally, those traitsthat have been acquired can be passed on to the next generation.
1809
According to the _, organisms could alter the size, shape, or structure of particular body parts or organs by continuously using them in new ways.
theory of use and disuse
One example of the _ is shown in figure 8.2. Lamarck proposed that giraffes used to have short necks. However, their increase in population caused a shortage in their food supply on the ground; thus, they tried to eat the leaves on the trees to survive.
To be able to reach these leaves, giraffes needed to stretch their necks, as Lamarck proposed. Thus, the longer necks.
theory of use
The _ states that if an animal chooses not to use its body part
that body part or organ ould eventually decrease in size for several generations until it finally disappears.
theory of disuse
The _ states that organisms inherited their traits from their parents, and that they may also pass them on to the next generation of offspring.
theory of inheritance of acquired characteristics
_ is the study of the distribution plants and animals on Earth. The distribution organisms in an environment can be used as important tool for explaining evolution.
Biogeography
A _ contains preserved remains or evidence of ancient organisms.
_ records provide strong evidence of the history of life on Earth. They also show how different groups of organisms have changed over time.
Fossil
Another evidence of evolution can be found by studying and comparing certain body part of different animals.
Homology
These structures may have different mature forms, but they all came from the same set of embryonic tissues.
homologous structures
Another piece of evidence involves the similarities in the early development of various organisms. Different organisms have similar structures during their early embryological development.
Embryology
The study of _ is important for identifying the evolution forganisms on Earth.
DNA and protein sequences
_ is the most advanced tool or evidence for evolution. Similarities in DNA sequences among organisms indicate their close relation with one another.
DNA sequencing
Taxonomy (from ancient Greek words _, which means “arrangement,” and _, which means “method”).
taxis; nomia
_ is a science that deals with the classification of organisms based on shared characteristics.
Taxonomy
• Was the first Greek philosopher to classify organisms
• Classified invertebrates and vertebrates as animals without blood and with blood, respectively
• Also divided animals based on how they give birth (e.g., live-bearing and egg-bearing), and grouped invertebrates into insects, crustaceans, and mollusks
Aristotle (384-322 BC)
• Wrote in his book Historia
Plantarum the different classification of 480 species of known plants
• Classified plants based on their growth forms
Theophrastus (372-287 BC)
• A Greek physician who traveled to Rome and Greece to gather information about medicinal plants
• Wrote the book De Materia Medica, which contained information on about 600 species based on their to yie
medicinal properties
Pedanius Dioscorides
(40-90 AD)
Wrote many books including Naturalis Historia, which is composed of 160 volumes on plants that were given Latin names
Gaius Plinius Secundus (23-79 AD)
Wrote De Plantis that showed information on 1 500 plant species, which are classified based on growth habits, as well as fruit and seed forms
Andrea Cesalpino
(1519-1603)
• Wrote the book Pinax Theatri Botanici (the word pinax means “register”) which contained information on 6 000 plant species
• Included the synonyms of plant species, which gave a semblance of order in the taxonomic world
• Recognized the genus and the species as major taxonomic levels of organisms
Bauhin Brothers
• Johann Bauhin (1541-1613)
• Gaspard Bauhin (1560 - 1624)
• Established the species as the ultimate unit of taxonomy
• Wrote and published the book Methodus Plantarum Nova, which contained information on 18 000 plant species as a result of relatively narrow species concept
• His classification of plants published in the book entitled Historia
Plantarum was an important step toward modern taxonomy
John Ray (1627-1705)
Published Institutiones Rei Herbariae, which consists of information on 9 000 plant species listed in 698 genera, based on floral characters
Joseph Pitton de Tournefort
(1656-1708)
• Developed binary nomenelature, which is still used today by taxonomists
• Published several books including Species Plantarum and the 10th edition of Systema Naturae, which were regarded as the starting points of modern botanical and zoological taxonomy
• Categorized and classified at least 8 o00 different plants and animals based on their morphological characteristics
Carl Linnaeus (1707-1788)
Wrote the book Familles des Plantes, which gave an idea that classifying organisms should be based on a great range of characters
Michel Adanson (1727-1806)
• Changed the system of plant classification with his published book Genera Plantarum
• Established the “family” rank as that between “genus” and “class”
Antoine Laurent de Jussieu
(1748-1836)
Introduced the three-kingdom scheme by adding Kingdom Protista
Ernst Haeckel (1834-1919)
Coined the term prokaryotes (cells without nucleus) and eukaryotes (cells with nucleus)
Edouard Chatton (1883-1947)
Established the four-kingdom classification scheme
Herbert Copeland (1902-
1968)
Introduced the five-kingdom classification scheme by introducing Kingdom Fungi
Robert Whittaker (1920-1980)
Introduced Kingdom
Archaebacteria in the 19705, which led to the rise of the three-domain system two decades later
Carl Woese (1928-2012)
The natural system of classification based on the evolutionary history or genealogy shared by a group of organisms is known as _.
phylogeny
The phylogeny of organisms can be traced using _. These show the evolutionary relationships of organisms based on the best available pieces of evidence.
phylogenetic trees
The best way that scientists can draw phylogenetic trees is by using _.
This is an analytical method of refining the evolutionary classification of organisms. It involves identifying shared derived characteristics.
Cladistics
Shared derived characteristics can be shown in a _. It is a diagram that represents the evolutionary relationships among organisms.
cladogram
The _ comes from the Greek word which means “divided in two parts.” This relatively simple tool for classifying organisms uses two opposite characteristics with the help of following specific directions that can lead you to the identity of an organism or a system.
It is composed of a series of paired statements or traits laid out in a numbered sequence.
dichotomous key
The _ uses Latin words, the language commonly used by 18th-century scientists. This practice is stil folowed today in naming newly discovered species.
scientific name
_ offered the first comprehensive, consistent, and much simpler method of naming and organizing species, which is now called binomial nomenclature.
Carl Linnaeus (or Carolus Linnaeus)
The _ is a two-word naming system used to name a species. In this naming system, each species is assigned a two-part scientifie name, wherein the first letter of the first word is capitalized and the second word is set in lowercase.
binomial nomenclature
A group of closely related species.
genus
It describes an important trait or the location where the organism lives.
specific epithet
Four things to note when creating a specific epithet
- organisms’s mahor characteristics/its common local name
- locality, collector, or eminent person
- some of the characteristics of the species
- ecological name/habitat to which the organism was first observed
In taxonomy, a group or level of organization is called a _.
taxonomic category/taxon
Taxa
Kingdom
Phylum
Class
Order
Family
Genus
Species
The largest and most inclusive among the Linnaean taxa.
Kingdom
During Linnaeus’s time, he only classified two kingdoms, namely, _ and _. This taxon has the greatest variety of organisms.
Kingdom Animalia and Kingdom Plantae
Kingdom includes the following:
eubacteria
archaebacteria
fungi
plants
animals
Kingdoms ure made up of different phyla (singular: phylum). _ is one of the major taxa used in classifying organisms.
Phylum
A _ is a subdivision of a phylum. It is a taxon that broadly includes the major organisms that are distinct from other organisms internally and externally.
class
An _ is a broad taxon composed of a number of similar families. In this taxon, organisms are generally classified based on their characteristics.
order
A _ is a taxon that includes one or more genera that share a common phylogenetic origin. This consists of a number of genera with similar characters. This designates a category of classification that is fairly precise.
family
A _ is a taxon that includes one or more species with common phylogenetic traits. This is used as the first part of the scientific name.
genus
The _ is the basic unit of classification. This is used as the specific epithet in the scientific name. This taxon is made up of organisms that can both interbreed and produce fertile offspring.
species
The _ was first established by _, in which he divided organisms into plants and animals based on his observations.
two-kingdom system of classification;
Aristotle
Animal subgroups are based on their habitat:
land, air, and water
plant subgroups are based on their size:
small, medium, large
His version of the two-kingdom system was used for 2 000 years until Carl Linnaeus published his improved version of the two-kingdom system in the 1700s, which divided the kingdoms into five levels:
class
order
genus
species
variety
In the two-kingdom system, those that are stationary and depend only on the sun to produce their own food are generally categorized as _.
plants
Those that move and get energy from other organisms are called _.
animals
Scientists found out that microorganisms are strikingly different from plants and animals. Thus, the two-kingdom classification scheme was revised into a _ scheme to accommodate microorganisms.
three-kingdom classification
The use of microscopes also helped scientists such as the German naturalist _ to introduce Kingdom Protista where he grouped the microscopic, unicellular organisms that have intermediate characteristics of plants and animals under Kingdom Protista.
Ernst Haeckel
Further developments in microscopy led the French marine biologist _ to introduce the term _ and _.
Edouard Chatton; prokaryotes and eukaryotes
Edouard Chatton defined _ as organisms without nuclei in their cells and _ as those with nuclei, which enabled the establishment of empires (precursor to domain system).
prokaryotes; eukaryotes
From this establishment, _, an American biologist, proposed the four-kingdom classification scheme. He grouped all prokaryotes under _.
Herbert Copeland; Kingdom Monera
In 1969, _, an American ecologist, introduced _, which includes stationary organisms that are not photosynthetic. With this addition, he had proposed the five-kingdom classification scheme.
Robert Whittaker; Kingdom Fungi
With the dawn of molecular studies in the 1970s, a group of scientists led by _ proposed that Kingdom Monera can be further divided into Kingdom Eubacteria and Kingdom Archaebacteria.
Carl Woese
The organisms under the newly discovered _ have a distinct plasma membrane and cell wall.
Kingdom Archaebacteria
Due to the fast-paced advancement of technology, scientists have proposed numerous ways to classify organisms in a more specifie approach. One of these proposed classifiention schemes is the _.
eight-kingdom scheme
In eight-kingdom scheme, Kingdom Protista is subdivided into:
Kingdom Archezoa
Kingdom Protozoa
Kingdom Chromista
This enabled him to establish the _, which replaced the two-empire system:
Kingdom Eubacteria is now classified under Domain Bacteria; Kingdom Archaebacteria is now classified under Domain Archaea; and Kingdom Eukaryota became Domain Eukarya.
three-domain system of classification
The three-domain classification system is also called the?
phylogenetic tree of life
The members of _ are the organisms under Kingdom Eubacteria. They are unicellular, prokaryotic organisms.
Domain Bacteria
Organisms of Domain Bacteria have thick and rigid cell walls composed of a substance known as _.
peptidoglycan
Members under _ include Kingdom Archaebacteria. Like the organisms under Domain Bacteria, all of its members are unicellular and prokaryotic. They have cell walls that lack peptidoglycan, and their cell membranes have lipids that are not found in other organisms.
Domain Archaea
_ derives its name from the eukaryotic cells of the organisms included in this domain. Being eukaryotic is the main feature that unites Kingdoms Protista, Fungi, Plantae, and Animalia into this domain.
Domain Eukarya
Among all the members of Domain Eukarya, _ are the most biologically diverse.
There are different groups of _ that cannot be classified as plants, animals, or fungi; thus
they are called plantlike, animal-like, and fungal-like protists.
protists
Members of _ cannot make their own food. They can only absorb their food from their surroundings into their bodies.
Kingdom Fungi
Members of _ include all plants. They are multicellular organisms that create their own food by photosynthesis. They cannot move from one place to another.
Kingdom Plantae
Members of _ are multicellular and heterotrophic. Animal cells do not have cell walls. Most of them can move, although a few are nonmotile in their adult forms such as sponges.
Kingdom Animalia
