Questions on Biology Essay

List properties of living things. 1 . Living Things are Composed of Cells: (Homeostasis) 2 Living Things Have Deterrent Levels tot Organization: 3. Living Things Use Energy: (Metabolism) 4. Living Things Respond To Their Environment: (Response to stimuli) 5. Living Things Grow: 6. Living Things Reproduce: 7. Living Things Adapt To Their Environment: (Adaptation) Explain the taxonomy of living things. What is taxonomy? Taxonomy is the science of naming, describing and classifying organisms and includes all plants, animals and microorganisms of the world.

Using morphological, behavioral, genetic and biochemical observations, taxonomists identify, describe and arrange species into classifications, including those that are new to science. Taxonomy identifies and enumerates the components of biological diversity providing basic knowledge underpinning management and implementation of the Convention on Biological Diversity. Unfortunately, taxonomic knowledge is far from complete. In the past 250 years of research, taxonomists have named about 1. 8 million species of animals, plants and micro-organisms, yet the total number of species is unknown and probably between 5 and 30 million.

Describe the naming system used for species. A group of living organisms consisting of similar individuals capable of exchanging genes or interbreeding. The species is the principal natural taxonomic unit, ranking below a genus and denoted by a Latin binomial, e. G. , Homo sapiens. This is the order of the pyramid goes starting at the top Domain, Kingdom, Phylum, Order, Class, Family, Genus Species. Domain is the biggest. It can consist of millions of species. Then you get a little more specific. You come to the Kingdom. This usually consists of thousands of species.

Then you get more specific. You come to the Phylum, then order class, Family genus, and finally to species. He also came up with a system known as binomial nomenclature. It helps you determine how similar species are in the system that Linnaeus used to classify organisms into all the groups beginning with Domain. The binomial naming system is the system used to name species. Each species is given a name that consists of two parts. The first part is the Genus to which the species belongs and the second part is the species name. What is a population?

A population is a summation of all the organisms of the same group or species, who live in the same geographical area, and have the capability of interbreeding. What is phylogeny and why is studying it important? How can this study be applied? Is the history of the evolution of a species or group, especially in reference to lines of descent and relationships among broad groups of organisms. Fundamental to phylogeny is the proposition, universally accepted in the scientific community, that plants or animals of different species descended from common ancestors.

The evidence for such relationships, however, is nearly always incomplete, for the vast majority of species that have ever lived are extinct, and relatively few of their remains have been preserved in the fossil record. Most phylogeny’s therefore re hypotheses and are based on indirect evidence. Different phylogeny’s often emerge using the same evidence. Nevertheless, there is universal agreement that the tree of life is the result of organic descent from earlier ancestors and that true phylogeny’s are discoverable, at least in principle.

Phonetics versus classicists The methodology of phylogeny work rests on two approaches: phonetics and phylogeny systematic (classicists). Phonetics bases classification strictly on similarities among organisms and emphasizes numerical analyses of an observed set of phenotypes characteristics. Classicists bases classification of a group of species solely on their most recent common ancestor. Classicists only uses shared derived characters-?that is, select characteristics that infer monopoly or those that are expressed in all descendants of a common ancestor.

The most direct difference between the two methods is that phonetics classifies species using as many characteristics as possible and arranges them by similarity regardless of any evolutionary relationships. What do derived characteristics tell us about classes? Classicists (from Greek XX;q, skalds, I. E. “branch”)[l] is an approach to biological localization in which organisms are grouped together based on whether or not they have one or more shared unique characteristics that come from the group’s last common ancestor and are not present in more distant ancestors.

Therefore, members of the same group are thought to share a common history and are considered to be more closely related. An phonograph (“separate form”) or derived state is an innovation. It can thus be used to diagnose a Claude – or even to help define a Claude name in phylogeny nomenclature. Features that are derived in individual tax (a single species or a roof that is represented by a single terminal in a given phylogeny analysis) are called autobiographies (from auto-, “self”). Autobiographies express nothing about relationships among groups; classes are identified (or defined) by seismographs (trot sync-, “together”).

For example, the possession tot digits that are homologous with those of Homo sapiens is a contemporary within the vertebrates. The attracted can be singled out as consisting of the first vertebrate with such digits homologous to those of Homo sapiens together with all descendants of this vertebrate (an phonograph-based phylogeny Importantly, snakes and other trapped that do not have digits are nonetheless attracted: other characters, such as amniotic eggs and dipped skulls, indicate that they descended from ancestors that possessed digits which are homologous with ours.

What is a monopolistic group? Give examples of monopolistic groupings, A monopolistic group, sometimes called a Claude, includes an ancestral taxonomy and all of its descendants. A monopolistic group can be separated from the root with a single cut, whereas a non-monopolistic group needs two or more cuts. What is a clamored? Classicists is a powerful modern tool for studying and understanding evolution. Classicists attempts to do for the entire history of life what genealogy does for the history of human families: to disentangle the relationships between all living beings.

But while genealogy focuses on detailed lineages of ancestry and descent, classrooms focus on identifying the common ancestry of related groups. Classify living things according to biological categories. What are the evolutionary origins of the three domains? The three-domain system is a biological classification introduced by Carl Woes in that divides cellular life forms into arched, bacteria, and creationism’s.

In particular, it emphasizes the separation of prokaryote into two groups, originally called Bacteria (now Bacteria) and Architectural (now Arched). Woes argued that, on the basis of differences in ASS rearrange, these two groups and the eukaryote each arose separately from an ancestor with poorly developed genetic machinery, often called a progenitor. To reflect these primary lines of descent, he treated each as a domain, divided into several different kingdoms.

Woes initially used the term “kingdom” to refer to the three primary phylogeny groupings now offered to as “domains,” until the latter term was coined in 1990. [2] Describe how the three domains are related to each other, and how they differ. Domain Arched – prokaryotic, no nuclear membrane, distinct biochemistry and RNA markers from bacteria, possess unique ancient evolutionary history for which they are considered some of the oldest species of organisms on Earth; traditionally classified as architectural; often characterized by living in extreme environments.

Some examples of archival organisms are methanol’s which produce the gas methane, hillsides which live in very salty water, and thermoplastics which hire in acidic high temperature water. Domain Bacteria – prokaryotic, consists of prokaryotic cells possessing primarily dyadic glycerol disaster lipids in their membranes and bacterial RNA, no nuclear membrane, traditionally classified as bacteria. Most of the known pathogenic prokaryotic organisms belong to bacteria (see [3] for exceptions), and are currently studied more extensively than Arched.

Some examples of bacteria include Contractible photosynthesis bacteria that are related to the chloroplasts of eukaryotic plants and algae, Spirochetes – Gram-negative bacteria that include hose causing syphilis and Lame disease, and Firmest – Gram-positive bacteria including Bidirectional animals which is present in the human large intestine. Domain Eukaryote – eukaryote, organisms that contain a membrane bound nucleus.

An in-exhaustive list of eukaryotic organisms includes: Kingdom Fungi or fungi Examples: Scarification – includes true yeasts Biostatistics – includes blue oyster mushrooms Kingdom Plantar or plants Bryophyte – mosses Magnanimously – flowering plants Kingdom Mammalian or animals Arthropod – includes insects, arachnids, and crustaceans Chordate – includes vertebrates and, as such, human beings Kingdom Chromatically – a group of eukaryote that represent descent from an organism that had an endometriosis between a line related to a bikini and a red alga.

However, the monopoly of the of this group is challenged. Describe the characteristics and diversity of the Protests. What role do they play on earth? Give examples of organisms in this kingdom. Kingdom Prosiest is a diverse group of eukaryotic organisms. Protests are unicellular, some are colonial or multicultural, they do not have specialized tissue organization. The simple cellular organization distinguishes the protests from other eukaryote. The cell body of the protests contain have a nucleus which is well defined and membrane bound organelles.

Some have flagella or cilia for locomotion. Reproduction in protests is both asexual and sexual. They live in any environment that contains water. All single celled organisms are placed under the Kingdom Prosiest. The term Prosiest was first used by Ernst Hackle in the year 1886. This kingdom forms a link between other kingdoms tot plants, animals and tuning. Protests represent an important step in early evolution. The first protests evolved probably 1. 7 billion years ago. Members of Prosiest are primarily aquatic in nature. It is a very large group comprising of at least 16 phyla.

Many protests like algae are the primary producers in the aquatic ecosystem, some protests are responsible for serious human diseases like malaria and sleeping sickness. EVOLUTION Describe the processes of evolution What are sources of variation? 1. Mutation. This is some error in the replication of DNA during cell division. This is a *huge* category as there are many kinds of mutations. The most important (from the point of view of evolution) is gene duplication (also called ‘gene amplification’). But here are also point mutations, substitutions, deletions, insertions, frameset errors, translations, transpositions, inversions, etc. . Sexual combination. This refers to the fact that any mating between two individuals produces an offspring with a genome different from *either* of its parents. This is a *huge* source of variation within a population, as it produces many different *combinations* of traits, each of which can have its own advantages and disadvantages. Thus sexual reproduction can produce far more variation than asexual reproduction, where all variation is dependent on mutations. 3. Recombination and crossing over. This refers to processes during various stages of DNA replication where DNA is broken and then Joined to other chromosomes.

The most common form of this is crossing-over during meiosis where DNA is exchanged between homologous chromosomes, but there are other processes, such as end- joining between non-homologous chromosomes that can occur. 4. Horizontal gene transfer. This refers to any process that can move DNA between individuals in a method other than inheritance. (Inheritance is sometimes called ‘vertical gene transfer’. ) For example, viruses can transfer DNA between bacteria, even completely unrelated bacteria. Bacterial conjugation is another way of transfer.

This is common in prokaryote (like bacteria), and may in fact be very important in the early evolution of single-celled organisms (which is why the *base* of the evolutionary tree is much more murky than the evolution of multicultural eukaryote, like us vertebrates). However, there is some evidence of a small amount of horizontal transfer of some DNA between *species* in evolution. Define and give examples of the following types of selection: directional, stabilizing, disruptive. Natural selection can take many forms. To make talking about this easier, we will consider the distribution of traits across a population in graphical form.

In we see the normal bell curve tot trait distribution. For example, it we were talking about height as a trait, we would see that without any selection pressure on this trait, the heights of individuals in a population would vary, with most individuals being of an average height and fewer being extremely short or extremely tall. However, when selection pressures act on a trait, this distribution can be altered. Stabilizing selection When selective pressures select against the two extremes of a trait, the population experiences stabilizing selection.

For example, plant height might be acted on by stabilizing selection. A plant that is too short may not be able to compete with other plants for sunlight. However, extremely tall plants may be more susceptible to wind damage. Combined, these two selection pressures select to maintain plants of medium height. The number of plants of medium height will increase while the numbers of short and tall plants will decrease. Directional selection In directional selection, one extreme of the trait distribution experiences selection against it.

The result is that the population’s trait distribution shifts toward the other extreme. In the case of such selection, the mean of the population graph shifts. Using the familiar example of giraffe necks, there was a selection pressure against short necks, since individuals with short necks could not reach as many leaves on which to feed. As a result, the distribution of neck length shifted to favor individuals with long necks. Disruptive Selection In disruptive selection, selection pressures act against individuals in the middle of the trait distribution.

The result is a bimodal, or two-peaked, curve in which the two extremes of the curve create their own smaller curves. For example, imagine a plant of extremely variable height that is pollinated by three different pollinators, one that was attracted to short plants, another that preferred plants of medium height and a third that visited only the tallest plants. If the pollinator that preferred plants of medium height disappeared from an area, medium height plants would be selected against and the population would tend toward both short and tall, but not medium height plants.

Such a population, in which multiple distinct forms or morphs exist is said to be polymorphic. What is natural selection? Natural selection is the gradual process by which biological traits become either more or less common in a population as a function of the effect of inherited traits on the differential reproductive success of organisms interacting with their environment. It is a key mechanism of evolution. The term “natural selection” was popularized by Charles Darwin who intended it to be compared with artificial selection, now more commonly referred to as selective breeding. What is sexual selection?

Sexual selection is a mode of natural selection in which some individuals out- produce others of a population because they are better at securing In Darwin described sexual selection as an important process driving species evolution and as a significant element of his theory of natural selection, but this concept was only named in his 1859 book On the Origin of Species. The sexual form of selection How do the following affect diversity in a population: nonrandom mating, multiple alleles, genetic drift, bottlenecks, founder effect, gene flow. Genetic drift is a change in allele frequencies in a population due to chance alone.

Bottleneck is a drastic reduction in population size as a result of severe selection pressure. Founder effect the new population differs from the original population. Gene flow is the movement of allele into and out of a population. Describe the following examples of evolution: super rats, peppered moths, sickle cell anemia, honeymooner’s in Hawaii. What is speciation? How does it occur? Evolutionary process in which new species arise. The details of speciation differ every time it occurs, putrefactive isolation, the end of gene flow between populations, is always a part of the process.

With allophonic speciation, a geographic barrier arises and interrupts gene flow between populations. After gene flow ends, genetic divergences that occur independently in the populations result in separate species. Speciation can also occur with no barrier to gene flow, a pattern called symmetric speciation. What are copulation, stasis, expiation, mass extinction, and adaptive radiation? Give examples for each. Copulation is The Joint evolution of two closely interacting species; each species is a selective agent for traits of the other.