Classification, Kingdoms, Bacteria, Viruses, Immune System, Genetics, Evolution and Plants

Flashcards covering vocabulary terms related to classification, kingdoms, bacteria, viruses, immune system, genetics, evolution, plants and other related topics.

Biosphere

All ecosystems

Ecosystem

Biotic and abiotic factors

Community

Group of organisms living together

Population

Organisms of a particular species

Organism

A living thing

Organ system

Organs that work together

Organ

Made of tissue

Tissue

Made up of cells

Cell

Structural unit

Organelle

Specialized subunit within a cell

Molecule

Made up of at least two atoms

Atom

Central nucleus surrounded by electrons

Species

All organisms capable of breeding freely with each other under natural conditions

Binomial nomenclature/Linnaean system of classification

System used for naming organisms; contains a 1st name that is capitalized and in italics (or underlined) & a 2nd name that is not capitalized, in italics(or underlined)

Taxonomy

The science of classifying all organisms; classifys both living and fossil species

Phylogeny

The study of the evolutionary relatedness between and among species: shown using a phylogenetic tree.

Dichotomous Key

A series of branching two-part statements used to identify organisms or objects

7 Levels of Organization

Kingdom-Phylum-Class-Order-Family-Genus-Species

Variety of all living things and their interactions

Biodiversity

Genetic diversity

Differences in genetic make up in organisms, usually in the same species

Species diversity

A measure of diversity that takes into account the quantity of each species present as well as the variety of different species present

Structural diversity

The range of physical shapes and sizes within a habitat or ecosystem

Characteristics of Bacteria

All bacteria are single celled- All bacteria are prokaryotic (lack nucleus and membrane‐bound organelles)- All bacteria reproduce asexually by binary fission (their mitosis)- All bacteria contain DNA made of a single chromosome

Nitrogen Fixation

Some bacteria take nitrogen directly from the air to make proteins.

Flagellum

Whip‐like tail for movement, not always present

Plasmid

A loop of DNA which is exchanged during conjugation

Capsule

Reduces water loss, resists high temperatures and protects against antibiotics & viruses

Gram‐positive

Stained purple after a dyeing technique with crystal violet and iodine; these bacteria have a thick cell wall and are mostly harmless

Gram‐negative

Stained pink; these bacteria have a thin cell wall and many are pathogenic, can make sick not always

Heterotrophic

Must eat others for food

Autotrophic

Able to make own food

Aerobic (aerobes)

Use oxygen to produce energy from food

Anaerobic

Do not require oxygen to produce energy

Conjugation

Two bacterial cells connect via a bridge (a pilus) and exchange a plasmid (a small ring of DNA).

Endospore Formation

Occurs with gram‐positive bacteria. When growth conditions become unfavourable, the bacterium makes an endospore (a thick wall that surrounds its DNA and cytoplasm).

Endotoxins

Produced inside bacteria and are only released when gram‐negative bacteria split they are seldom toxic, but do cause fever, diarrhea, and vomiting

Exotoxins

Produced and excreted from living bacteria they do not produce fevers, they are often fatal

Viruses

Parasitic and cannot live independently, cannot invade all cell types, must use the energy of other cells to “live” and reproduce

Bacteriophage

Attaches to cell surface and inject their genetic material

Lytic cycle

Virus attaches to cell and injects DNA into cell, viral DNA uses bacterial cell components to manufacture more viruses, Occurs very fast,destroys cells; viral symptoms are immediate

Lysogenic cycle

Virus DNA combines with cell Dna, Occurs slowly, viral symptoms are delayed

Simple RNA

Takes over cell functions directly, Avoids cell DNA entirely

Retrovirus

Uses an enzyme to rewrite cell DNA the viral RNA, Enzyme makes frequent mistakes thus has a very high mutation rate, Long,slow life cycle, turns RNA into DNa

Cell Lysis

Kills host virus particles build up inside cell; cell eventually bursts open

Exocytosis

Exit movement, keeps host alive, Virus is exported out of cell; no damage to cell structure, Can continue to make viruses

Zoonotics

Disease Transmission Across Species

Viroids

Infectious pieces of RNa, Do do not code for protein, Smaller than a virus, Have no capsid/protein coat, Are plant pathogens that destroy crops

Parasites

Live off their hosts to survive

Helminths

Parasitic worms across 4 phyla, Tapeworms, Roundworms, Flukes, Most are intestinal parasites

Protozoa

Animal‐like protists, Spread through insect vector infected items

Malaria

Mosquito‐borne disease, Caused by members of the genus Plasmodium

Toxoplasmosis

Caused by Toxoplasma gondii, Spread by infected food, cat-feces, mother‐to‐fetus

Ectoparasites

A parasite the lives on the outside of the host

Skin

Layers of cells with top layers that are dead and act as a barrier

Mucosa

Covers body openings (respiratory, digestive, reproductive, eyes) with a layer of mucus

Able to damage or kill bacteria; found in tears, saliva and milk

Lysozyme

Innate Immune System (Nonspecific Immunity)

Identify and remove foreign material, Recruit immune cells with cytokines, Activate complement cascade, Activate adaptive immunity

Cells Involved in Innate Immune System

Macrophages, natural killer cells, and granulocytes

Phagocytes

Eating, phagocytosis-cell eating, kills, recruit other immune cells, links innate and adaptive immunity

Granulocytes

Many granules in cytoplasm, granules are toxic, killing pathogens (inject toxins in pathogen), immune signalling, regulate functions of other immune cells

Natural killer cells

Destroy host cells that are compromised (cancer) or virus infected. Cause cell death by: cell lysis (break cell membrane), apoptosis (programmed cell death)/ Do not need activation by other immune cells.

Adaptive Immune System (Acquired Immunity)

Recognize “self” and “non‐self” during antigen‐presentation, Generate immune responses specific to the pathogen, Create and maintain immune memory

Cells Involved in Adaptive Immune System

T Cells and B Cells

Where do T Cells originate?

Thymus at branch of trachea, when you were young

Memory T Cells

Cells that live after infection, remember how to fight infection, with you for years, protect you next time

Where do B Cells originate?

Bone marrow and no training

Proteins made by B cells, Bind to antigen to remove pathogen

Antibodies

Lymphatic System

A network of lymphatic vessels, lymph nodes, lymphatic organs, lymphatic tissues; site of activation for the adaptive immune system

Thymus

Produces and trains T-cells

Bone Marrow

Spongy tissue inside bones that creates blood cells (including immune cells)

Spleen

Stores B and T Cells (and red blood cells), Contains macrophage to remove dead/dying immune cells, Filters blood

Apoptosis

Regulated process of cell death

Allergies

Harmless antigen(s) cause an immune response, Linked to the IgE antibodies

Autoimmune

Immune cells do not properly distinguish “self” vs “non‐self” antigens, Immune system attacks your own tissues

Immune Deficiency

One or more components of the immune system are inactive

Non-Specific immune system defenses

Work against all kinds of pathogens, Always present-Include: Chemical and Physical barriers: skin, sweat, tears, earwax, cilia, acids, coughing, sneezing and vomiting, Resident microorganisms: live on you and prevent invaders from colonizing you, Inflammation and Fever

Specific immunity

Adaptive cells that takes time to develop but can remember specific pathogens to destroy them

Antibiotics

Medications that kill bacteria

Antiviral agents

Target specific viruses but do not kill, but don’t allow virus reproduction/development

Kill or inhibit fungi

Fungicides

Chromosomes and Genes

In somatic cells the chromosomes are made of DNA. A segment of DNA is called a gene

Alleles

The different forms of expression of a gene

Genotype

The specific alleles a person has

Phenotype

The observable traits a person has

True Breeding Organism

An organism that produces offspring that are genetically identical for 1+ traits when self-pollinated or crossed with another true-breeding organism for the same traits

Trait

A particular version of an inherited characteristic

Hybrid

Offspring of two different true-breeding organisms

Cross

The successful mating of two organisms from distinct genetic lines

P generation

Parent plants used in a cross

F1 generation

Offspring of P-Generation cross

Monohybrid

The offspring of 2 different true-breeding plants that only differ in 1 characteristic

Monohybrid cross

A cross designed to study the inheritance of 1 trait

F2 generation

Offspring of an F1-generation cross

Test Cross

Crossing the unknown with a homozygous recessive

Complete dominance

Heterozygote phenotype expresses only the dominant trait.

Incomplete dominance

Heterozygote phenotype is blendend that of two homozygotes

Codominance

Non-identical alleles specify two phenotypes that are both expressed in heterozygotes, (spotted/striped)

Autosomal chromosomes

Chromosome pairs 1-22 : Responsible for determining non-sexual characteristics

Sex Chromosomes

The 23rd of chromosomes [x and y], Responsible for determining the sex and sex-related traits

Multiple Alleles

Results in a larger number of possible genotypic combinations and a greater variety of phenotypes.