U4 Flashcards
What is Classification?
The grouping of information or objects based on similarities.
What is Taxonomy?
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?
To avoid confusion, as many common names vary from region to region and country to country.
Who proposed the hierarchy of complexity in organisms?
Aristotle.
What is the scala naturae?
The dominance of humans over all living things, described as a ‘ladder of nature’.
Who is known as ‘The Father of Taxonomy’?
Carolus (Carl) Linnaeus.
What is Binomial Nomenclature?
A two-name system for writing scientific names, consisting of a genus name and a species name.
What is the first name in Binomial Nomenclature in CAPITAL LETTERS ?
Genus name.
What is the second name in Binomial Nomenclature?
Species name.
What are the 7 levels of classification (taxa)?
- Kingdom
- Phylum
- Class
- Order
- Family
- Genus
- Species
What is Phylogenetics?
Classification based on common evolutionary descent.
What is the cornerstone of systematic taxonomy?
Phylogeny.
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 Prokaryotic organisms?
Unicellular organisms with no nucleus and no membrane-bound organelles.
What are Eukaryotic organisms?
Organisms that contain a nucleus and membrane-bound organelles.
What classification system did Aristotle propose?
Divided living organisms into plants and animals.
What are the two kingdoms in Linnaeus’s classification system?
- Plantae
- Animalia
What classification system did Robert Whittaker propose?
A five kingdom system consisting of Plantae, Animalia, Fungi, Protista, and Monera.
What characterizes the kingdom Plantae?
Immobile, multicellular eukaryotes that produce food by photosynthesis.
What characterizes the kingdom Animalia?
Multicellular, heterotrophic eukaryotes capable of mobility at some stage of their lives.
What characterizes the kingdom Fungi?
Eukaryotic, heterotrophic, usually multicellular group that obtains energy by decomposing dead organisms.
What characterizes the kingdom Protista?
Ancient eukaryotic kingdom that includes a variety of eukaryotic forms not classified as fungi, animals, or plants.
What characterizes the kingdom Monera?
Composed of prokaryotic organisms, lacking membrane-bound organelles and multicellular forms.
What are Archaebacteria?
Unicellular, prokaryotic organisms that exist in extreme environments.
What are Eubacteria?
Unicellular, prokaryotic organisms that can be heterotrophic, autotrophic, or chemotrophic.
What is the Six Kingdom System?
- Eubacteria
- Archaebacteria
- Protista
- Fungi
- Plantae
- Animalia
What is a phylogenetic tree?
A diagram that represents evolutionary relationships among species.
What is a branch point in a phylogenetic tree?
Represents the most recent common ancestor of all species on the branches.
What is a root in a phylogenetic tree?
The node closest to the root represents the most recent common ancestor for all organisms in the tree.
What is the structure of a virus?
A tiny particle of genetic material (RNA and DNA) with an outer coat of protein.
How do viruses replicate?
Virus injects itself into a living cell, takes over the cell’s activities, replicates, and then leaves the cell.
How are viruses transmitted?
By direct contact, contaminated objects, inhalation of aerosols, and through animal hosts.
What are some diseases caused by viruses?
- Flu
- Colds
- Covid-19
- HIV/AIDS
- Hepatitis
- Measles
- Polio
- Smallpox
What are some beneficial roles of viruses?
- Transfer genetic material
- Destroy harmful algal blooms
- Infect and destroy bacteria
- Reduce atmospheric carbon dioxide
What is the structure of bacteria?
Bacteria have cell walls, cell membranes, cytoplasm, hereditary material, and may have flagella.
What are the three possible shapes of bacteria?
- Cocci (sphere)
- Bacilli (rod)
- Spirella (spiral)
What is binary fission?
The method by which bacteria reproduce.
What are the two main types of organisms that bacteria can be classified as?
Parasites or saprophytes
Parasites feed on living material, while saprophytes feed on dead material.
What are the main structural components of bacteria?
Cell walls, cell membranes, cytoplasm, hereditary material, and may have flagella
Flagella are whip-like tail structures used for movement.
What is an endospore?
A thick outer coating that protects bacteria
Endospores help bacteria survive extreme conditions.
List the three possible shapes of bacteria.
- Cocci (sphere shape)
- Bacilli (rod shape)
- Spirella (spiral shape)
How do bacteria reproduce?
Through binary fission
They split into two cells.
How can bacteria be transmitted?
- Direct contact with an infected person
- Contaminated food or water (e.g., Salmonella, E. coli)
- Dirty objects (e.g., tetanus)
- Infected animals (e.g., rabies)
What are some harmful effects of bacteria?
- Terrorism
- Disease
- Tooth decay
- Food spoilage
List some helpful uses of bacteria.
- Antibiotics
- Nitrogen fixing
- Food production
- Tanning leather
- Breaking down waste products
- Digestion
Name some diseases caused by bacteria.
- Cholera
- Tuberculosis
- Lyme disease
- Pertussis
- Salmonella
- Staph infections
- Strep throat
- Leprosy
- Tetanus
- Diphtheria
- E. coli
- Flesh-eating disease (necrotizing fasciitis)
- Ricketts
What is an antibiotic?
A chemical substance that stops the growth of some microorganisms such as bacteria
Antibiotics are commonly used to treat bacterial infections.
What methods are used to treat bacterial infections?
- Antibiotics
- Sterilization (heat)
- Disinfectants and bleach
True or False: Bacteria consist of only a single cell.
True
What extreme conditions can some bacteria survive?
Temperatures above boiling point and extreme cold
Some bacteria can even withstand radiation levels lethal to humans.
Define infectious disease.
Diseases transmitted among people by harmful viruses or bacteria.
What is a host in the context of infectious diseases?
An organism in which another organism lives and gets nourishment and protection.
What are the body defenses against infection?
- Skin
- Mucous membranes
- Cilia
- Immune system (white blood cells)
What happens when invaders enter the body?
- Increase blood flow to the area (inflammation)
- Body temperature rises (fever)
- Production of white blood cells
- Production of interferon
- Production of antibodies
What is natural immunity?
Protection present at birth that prevents people from getting a disease.
What is acquired immunity?
Protection against disease that develops throughout a lifetime.
What are vaccines?
Substances that increase an organism’s immunity to disease.
What should be included in a poster comparing bacteria and viruses?
- Structure
- Shape
- Reproduction
- Transmission
- Diseases caused
- Treatments
- Helpful/Harmful effects
What is the study of chemical composition and reactions occurring in living matter?
Biomolecules
What do inorganic compounds not contain?
Carbon
What is the most abundant inorganic material in cells?
Water
What elements are found in organic compounds?
Carbon, hydrogen, and oxygen
What are the repeating units in polymers called?
Monomers
What are the long molecules formed by repeating patterns of monomers called?
Polymers
What is a functional group?
A group of atoms that characterize the structure of a family of organic compounds
List three types of functional groups.
- Amine (NH2)
- Carboxyl (COOH)
- Hydroxyl (OH)
What are the four types of macromolecules?
- Carbohydrates
- Lipids
- Proteins
- Nucleic acids
What is the ratio of atoms in carbohydrates?
1 C : 2 H : 1 O
What type of carbohydrate is one sugar?
Monosaccharide
What type of carbohydrate is two sugars linked together?
Disaccharide
What are the three types of lipids?
- Fats
- Oils
- Waxes
What two monomers typically make up lipids?
- Glycerol
- Fatty acids
What is the main function of lipids?
Store energy for later use
What type of fats contain only single bonds between carbon atoms?
Saturated fats
What are the building blocks of proteins?
Amino acids
What type of bond connects amino acids?
Peptide bond
What are the two types of proteins?
- Fibrous
- Globular
What is the primary structure of proteins?
The amino acid sequence
What is DNA?
Deoxyribonucleic acid
What is RNA?
Ribonucleic acid
What are the components of a nucleotide?
- Pentose sugar
- Phosphate group
- Nitrogenous base
What are the four nitrogenous bases in DNA?
- Thymine
- Adenine
- Cytosine
- Guanine
What are the four nitrogenous bases in RNA?
- Uracil
- Adenine
- Cytosine
- Guanine
What property must genetic material possess regarding replication?
It must replicate accurately
What is the speed of DNA replication in human cells?
3,000 nucleotides/min
What is the accuracy of DNA replication?
Very precise (1 error/1,000,000,000 nt)
What is the function of the cell membrane?
Regulates transport and gives structure to the cell
What does the cytoplasm do?
Supports and protects organelles; medium for chemical reactions
What is the function of the nucleus?
Contains genetic material (DNA)
What does the nucleolus produce?
Ribosomes
What is the role of ribosomes?
Synthesis of proteins
What does the rough endoplasmic reticulum (RER) help with?
Protein synthesis and transport
What is the function of the Golgi apparatus?
Modifies, processes, transports, and packages proteins
What does the mitochondria do?
Makes energy (ATP)
What is the function of lysosomes?
Breaks down waste and digests cellular components
What is the function of the cell wall?
Provides shape and support
What is the role of chloroplasts?
Makes photosynthesis
What do vacuoles store?
Water, nutrients, and waste
What do peroxisomes break down?
Fatty acids (lipids) and detoxify the cell
What is the function of centrioles/centrosomes?
Helps in cell division
