U4 - COMPLETA Flashcards
What is Classification?
Classification is the grouping of information or objects based on similarities.
What is Taxonomy?
Taxonomy is the science of grouping and naming organisms.
Why classify organisms?
To represent relationships among organisms, to make things easier to find, identify, and study, and to understand our own evolution.
Why use a scientific name?
We use scientific names to avoid confusion as many common names vary from region to region and country to country.
Who was Aristotle?
A Greek philosopher that proposed all creatures be arranged in a hierarchy of complexity.
What is the scala naturae?
The dominance of humans over all living things, described as the ‘ladder of nature’.
Who was Carolus Linnaeus?
A Swedish botanist/physician known as ‘The Father of Taxonomy’ who adopted a system of classifying and naming organisms.
What is Binomial Nomenclature?
A two name system for writing scientific names.
What are the components of Binomial Nomenclature?
Genus name – written first and always capitalized; Species name – written second and never capitalized.
How should Binomial Nomenclature be formatted?
Both words are to be italicized if typed, or underlined if handwritten.
What are the advantages of Binomial Nomenclature?
Indicates similarities in anatomy, embryology, and evolutionary ancestry.
What is an example of Binomial Nomenclature?
The North American black bear (Ursus americanus) and the grizzly bear (Ursus horribilis) are closely related.
Similar organisms are grouped into the same genus – in this case, Ursus.
What are the levels of classification?
7 levels known as taxa: Kingdom, Phylum, Class, Order, Family, Genus, Species.
What happens as one goes from Kingdom to Species?
An increase in the similarity between organisms occurs and there are fewer numbers of different kinds of organisms.
How are Kingdoms divided?
Kingdoms are divided into groups called phyla, which are subdivided into classes, orders, families, genera, and species.
What is the classification of humans?
Kingdom: Animalia, Phylum: Chordata, Class: Mammalia, Order: Primates, Family: Hominidae, Genus: Homo, Species: sapiens.
What is Phylogenetics?
Based on common evolutionary descent.
What is Phylogeny?
A representation of organisms based on and describing evolutionary relationships.
What is Systematics?
The study of the evolution of biological diversity.
What evidence is used in Phylogenetics?
Fossil record, morphology, embryological patterns of development, chromosomes, and DNA.
What are Autotrophs?
Organisms that make their own food by photosynthesis.
What are Heterotrophs?
Organisms that use organic materials for energy and growth.
What are Chemotrophs?
Organisms that get food by breaking down inorganic matter.
What are Prokaryotic organisms?
Unicellular organisms that have no nucleus and no membrane-bound organelles.
What are Eukaryotic organisms?
Organisms that contain a nucleus and membrane-bound organelles, most of which are multicellular.
What was Aristotle’s first classification system?
He divided living organisms into Plants and Animals.
What are the two kingdoms proposed by Carolus Linnaeus?
Plantae and Animalia.
What was Robert Whittaker’s Five Kingdom System?
It consisted of Plantae, Animalia, Fungi, Protista, and Monera.
What are the characteristics of Plantae?
Immobile, multicellular eukaryotes that produce their food by photosynthesis and have cells encased in cellulose cell walls.
Examples: Ferns, pine trees, roses.
What are the characteristics of Animalia?
Multicellular, heterotrophic eukaryotes capable of mobility at some stage during their lives, with cells lacking cell walls.
Examples: Humans, worms, spiders.
What are the characteristics of Fungi?
Eukaryotic, heterotrophic, usually multicellular group having multinucleated cells enclosed in cell walls, obtaining energy by decomposing dead organisms.
Examples: Mushrooms, moulds, yeast.
What are the characteristics of Protista?
The most ancient eukaryotic kingdom, including a variety of eukaryotic forms that are not fungi, animals, or plants.
Examples: Paramecium, amoeba, some algae, slime moulds.
What are the characteristics of Monera?
The only kingdom composed of prokaryotic organisms, having a cell wall and lacking membrane-bound organelles and multicellular forms.
Examples: Bacteria, blue-green bacteria (cyanobacteria).
What are Archaebacteria?
Unicellular, prokaryotic organisms that exist in extreme environments and do not need oxygen or light to live.
Examples: Methanogens, extreme thermophiles, extreme halophiles.
What are Eubacteria?
Unicellular, prokaryotic organisms that can be heterotrophic, autotrophic, or chemotrophic.
Examples: Bacteria, cyanobacteria (blue-green bacteria).
What is the Six Kingdom System?
It consists of Eubacteria, Archaebacteria, Protista, Fungi, Plantae, and Animalia.
What are phylogenetic trees used for?
Phylogenetic trees are used to study the evolutionary relationships among species.
How do scientists classify species?
Scientists classify species based on shared features; the more features shared, the more closely related the species are in evolution.
What anatomical features are used to study species relationships?
Shared anatomical features, such as the presence of a backbone, are used to study relationships.
What is a challenge in comparing species based on anatomical features?
Some features, such as the presence of wings, can make comparisons difficult or confusing.
What can be compared to study species relationships?
Molecular sequences (DNA, RNA, protein) can also be compared to study relationships.
How does sequence comparison differ from anatomical comparison?
Sequence comparison can be more objective and less ambiguous than anatomical comparison.
What has made DNA sequences widely available?
Rapid DNA sequencing technology has made many DNA sequences from different organisms available.
What do evolutionarily related organisms share?
Evolutionarily related organisms share a common ancestor with an ancestral DNA sequence.
What accumulates in DNA sequences as organisms evolve?
As organisms evolve and diverge, their DNA sequences accumulate differences, also known as mutations.
What are SNPs?
Single nucleotide polymorphisms (SNPs) are changes of one DNA base pair into another.
What are Indels?
Insertions and deletions (Indels) are mutations where one or more nucleotide pairs in a DNA strand are lost or gained.
How does the time since a common ancestor affect DNA similarity?
More distantly related species have had more time for mutations to accumulate in their DNA.
What is necessary before comparing DNA sequences?
Sequences must be aligned to ensure that related parts are compared.
How do computer programs assist in sequence alignment?
They maximize the number of matches among all sequences by adjusting their positions and adding gaps.
What does an asterisk indicate in a sequence alignment?
An asterisk indicates that all letters in that column match.
How is a SNP represented in an alignment?
A SNP is a position where the letters in a column do not match.
How is an Indel represented in an alignment?
An Indel is represented by a gap (sometimes a dash) in the alignment.
Can more than two sequences be aligned?
Yes, you can align multiple sequences to determine evolutionary relationships among many organisms.
What does the end of each branch in a phylogenetic tree represent?
The end of each branch represents a species or sequence, or a group of related species/sequences.
What is a branch point in a phylogenetic tree?
A branch point represents the most recent common ancestor of all the species on those branches.
What is the root of a phylogenetic tree?
The root is the node closest to the root of the tree, representing the most recent common ancestor for all organisms in the tree.
What are unrooted trees?
Unrooted trees show relative relationships among organisms without indicating the location of the common ancestor.
How are evolutionary relationships conveyed in phylogenetic trees?
They are conveyed by how the branches are arranged and connected to one another.
How do molecular phylogenetic trees relate to other evidence?
Phylogenetic trees made using DNA sequences are usually very similar to trees made using other evidence, such as comparative anatomy.
What can DNA sequence comparison clarify?
DNA sequence comparison can augment and clarify anatomical comparison.
What do phylogenetic trees explain?
Phylogenetic trees explain relatedness and can be generated using DNA sequence alignments.
What is the structure of a virus?
A tiny particle of genetic material (RNA and DNA) with an outer coat of protein. Not living UNTIL they inject themselves into a host (living) cell. May or may not have an outer spiky layer called the envelope. Can attack animals, plants, and humans. Biggest viruses are only as large as the smallest bacteria.
What is the shape of a virus?
Viruses come in all different shapes. Some viruses are shaped like a spaceship; they are called bacteriophages.
How do viruses replicate?
Virus injects itself into a living cell. Protein coat is discarded. Hereditary material takes over the cell’s activities. Virus replicates and the cell fills. Cell splits open. Viruses leave the cell and attack new cells.
Example of virus replication?
Bacteriophage cuts a hole in the cell wall and injects genetic material. The bacterial cell begins making new viruses.
How are viruses transmitted?
By direct contact with infected individuals; by contact with contaminated objects (such as toys, doorknobs); by inhalation of virus-laden aerosols (think sneezes); by animals that act as hosts (vectors).
What diseases are caused by viruses?
Flu, colds, Covid 19, HIV/AIDS, hepatitis, west nile, measles, herpes, shingles, chicken pox, monkeypox, polio, smallpox, ebola, and some cancers (epstein-barr) are just a few viruses that affect humans and animals. Tobacco mosaic and cauliflower mosaic are viruses that affect plants.
How are viruses helpful?
Transfer genetic material from species to species (allows for evolution), destroy harmful algal blooms, infect and destroy bacteria, reduce the amount of carbon dioxide in the atmosphere.
How are viruses harmful?
Cause disease and death, affect plant yields, infect animals such as birds and cows so they cannot be used for food.
How are viruses treated?
Vaccines which prevent the host from contracting the virus; antiviral drugs which treat the virus once contracted; let it run its course!
What are bacteria?
Bacteria are single-cell organisms so tiny that millions can fit into the eye of a needle. They are the oldest form of life on earth. Microbe fossils date back more than 3.5 billion years.
Where are bacteria found?
Bacteria are everywhere. There are more of them on a person’s hand than there are people on the entire planet! They are in the air we breathe, the ground we walk on, the food we eat—they’re even inside us!
What are the characteristics of bacteria?
Living organisms belonging to Kingdoms Archaeobacteria and Eubacteria. Most numerous organism on Earth but also the simplest.
What are the types of bacteria based on nutrition?
May be heterotrophic or autotrophic. Autotrophic = makes own food through photosynthesis. If heterotrophic they will be either parasites or saprophytes.
What is the structure of bacteria?
Bacteria have cell walls, cell membranes, cytoplasm, hereditary material, and may have a flagella, a whip-like tail structure used to move around.
What are the shapes of bacteria?
Come in three different possible shapes: Cocci = sphere shape, Bacilli = rod shape, Spirella = spiral shape.
How do bacteria reproduce?
Bacteria reproduce through binary fission; they split into two cells.
How are bacteria transmitted?
Direct contact with an infected person, contaminated food or water (Salmonella, E.coli), dirty objects (tetanus), infected animals (rabies).
How are bacteria harmful?
Terrorism, disease, tooth decay, food spoilage.
How are bacteria helpful?
Antibiotics, nitrogen fixing, food, tanning leather, breaking down waste products, digestion.
What diseases are caused by bacteria?
Cholera, tuberculosis, lyme disease, pertussus, salmonella, staph infections, strep throat, leprosy, tetanus, diptheria, E.coli, flesh eating (necrotizing fascitis) and ricketts.
How do we treat bacterial infections?
Antibiotic: A chemical substance that stops the growth of some microorganisms such as bacteria within the body. Sterilization (heat), disinfectants and bleach to kill bacteria before they can infect.
What is an infectious disease?
Infectious Disease (Communicable diseases): Diseases transmitted among people by harmful viruses or bacteria.
What are body defenses against infections?
- Skin, mucous membranes and cilia. 2. Immune system (white blood cells that fight infection).
How does the body respond to invaders?
- Increase blood flow to the area (inflammation). 2. Body temperature rises (fever). 3. Production of white blood cells. 4. Production of interferon. 5. Production of antibodies.
What are the types of immunity?
Natural immunity: Protection present at birth. Acquired immunity: Protection against disease that develops throughout a lifetime. Vaccines: Substances that increase an organism’s immunity to disease.
What are biomolecules?
Biomolecules are the study of chemical composition and reactions occurring in living matter.
What are inorganic compounds?
Inorganic compounds do not contain carbon, with exceptions like CO2, CO, and bicarbonates.
What is the most abundant inorganic material in cells?
Water is the most abundant and important inorganic material, making up 60% - 80% of all cells and 2/3 of body weight.
What are organic compounds?
Organic compounds contain the elements carbon, hydrogen, and oxygen.
What is the significance of carbon in organic compounds?
Carbon is found in things that are or once were living.
How do carbon atoms bond?
Carbon atoms share electrons to form covalent bonds.
What are monomers and polymers?
The single molecules in a polymer are called monomers, while the long molecules formed by repeating patterns of monomers are called polymers.
What is a functional group?
A functional group is a group of atoms that characterize the structure of a family of organic compounds.
What determines the properties of organic compounds?
Functional groups determine many of the properties of organic compounds.
What are the three types of functional groups to know?
The three types of functional groups to know are Amine (NH2), Carboxyl (COOH), and Hydroxyl (OH).
What are macromolecules?
Macromolecules are the four types of organic compounds: carbohydrates, lipids, proteins, and nucleic acids.
What is the function of carbohydrates?
Carbohydrates provide energy to the cells and are essential for maintaining life processes.
What is the structure of carbohydrates?
Carbohydrates contain a hydroxyl (OH) group and have a ratio of 1 C : 2 H : 1 O.
What are the types of carbohydrates?
Carbohydrates are classified as monosaccharides (one sugar), disaccharides (two sugars), and polysaccharides (many sugars).
What are lipids?
Lipids are fats, oils, and waxes that contain carbon, hydrogen, and oxygen.
What are the two monomers typically found in lipids?
The two monomers typically found in lipids are glycerol and fatty acids.
What is the function of lipids?
Lipids store energy for later use and serve as padding and protection for the body.
What is the structure of a phospholipid?
A phospholipid has a hydrophilic head (phosphate group) and hydrophobic tails (fatty acids).
What are proteins?
Proteins are the building materials for the body, composed of carbon, hydrogen, nitrogen, and oxygen.
What are the functions of proteins?
Proteins catalyze chemical reactions, synthesize and repair DNA, transport materials, receive/send signals, respond to stimuli, and provide structural support.
What are the building blocks of proteins?
The building blocks of proteins are amino acids, which are connected by peptide bonds.
What are the two types of proteins?
The two types of proteins are fibrous (hydrophobic) and globular (hydrophilic).
What is the primary structure of proteins?
The primary structure of proteins is the amino acid sequence.
What is DNA?
DNA (Deoxyribonucleic acid) is the genetic material of living organisms.
What is RNA?
RNA (Ribonucleic acid) is also a genetic material, made of a single polynucleotide strand.
What are nucleotides?
Nucleotides are the smaller molecules that make up DNA and RNA.
What are the four bases in DNA?
The four bases in DNA are Thymine, Adenine, Cytosine, and Guanine.
What are the four bases in RNA?
The four bases in RNA are Uracil, Adenine, Cytosine, and Guanine.
What are the properties of genetic material?
Genetic material must contain stable information, replicate accurately, and allow for variation.
What is the speed of DNA replication in humans?
The speed of DNA replication in humans is 3,000 nucleotides/min.
What is the accuracy of DNA replication?
DNA replication is very precise, with an error rate of 1 error per 1,000,000,000 nucleotides.
What is the function of the cell membrane?
Regulates the transport of what enters and leaves the cell. Gives structure to the cell.
What is the function of the cytoplasm?
Supports and protects organelles. Medium for chemical reactions.
What does the nucleus contain?
Contains genetic material (DNA).
What is the function of the nucleolus?
Produces ribosomes.
What is the function of ribosomes?
Synthesis of proteins.
What is the function of the rough endoplasmic reticulum (RER)?
Helps in protein synthesis and transports the proteins.
What is the function of the smooth endoplasmic reticulum (SER)?
Synthesis of lipids.
What is the function of the Golgi body / Golgi apparatus?
Modifies, processes, transports (lysosome), and packages proteins.
What is the function of the cytoskeleton?
Maintains cell shape and structure.
What is the function of mitochondria?
Makes energy (ATP).
What is the function of lysosomes?
Breaks down waste and digests cellular components.
CELL STOMACH
What is the function of the cell wall?
Provides shape and support.
What is the function of chloroplasts?
Makes photosynthesis.
What is the function of vacuoles?
Stores water, nutrients, and waste.
What is the function of peroxisomes?
Breaks down fatty acids (lipids) and detoxifies the cell.
What is the function of centrioles / centrosomes?
Helps in cell division.
