Diversity of Living Things Flashcards
What is taxonomy?
the science of defining groups of biological organisms on the basis of shared characteristics.
What are the biological groups?
Species, Genus, Family, Order, Class, Phylum, Kingdom, Domain
Carl Linnaeus
was a Swedish botanist. He developed the formal method of naming species called the Binomial Nomenclature.
Binomial Nomenclature
each species has 2 names (genus name) (species name). Genus is capital, species is not (italics).
What are the three domains?
Archaea, Bacteria, Eukarya
Archaea
Prokaryotic single-celled organisms similar in appearance to bacteria. Typically extremophiles, organisms that live in extreme environments like volcanos.
Bacteria
single-celled prokaryotic cells.
Eukarya
Eukaryotic cells, single or multicellular organisms with a nucleus. 4 kingdoms→ Protista, Plantae, Fungi, Animalia
Kingdoms
Eubacteria, Archaebacteria, Protista, Plantae, Fungi, Animalia
Phylogenetic Trees
Shows relations with common ancestors and descendants (ex. cladograms).
Dichotomous Keys
Method of determining unknown species with a series of choices that lead to correct species.
Biodiversity
The number and variety of species in ecosystems. They indicate the health of an ecosystem. The more species, the healthier the ecosystem.
Monoculture
the opposite of biodiversity. Ex. bananas since they are clones. If one is diseased, others will most likely be as well.
Levels of Biodiversity
Species Diversity, Genetic Diversity, Ecosystem Diversity
Species Diversity
How many types in an area
Genetic Diversity
Of the species present, how many different characteristics.
Ecosystem Diversity
Largest scale of biodiversity. It looks at how many different ecosystems in an area.
Species
When two individuals can make an offspring that is infertile, or if those individuals can’t make offspring altogether.
Species Diversity
A variety of species found in a discrete geographical area. Usually measured in total number.
Importance of Biodiversity
Maintain or restore healthy ecosystem functioning
Photosynthetic fixation of solar energy, the energy input for the world.
Water cycles and protects watersheds
Storage
Keystone Species
A Keystone Species is one that other species in an ecosystem heavily depend on. If Keystone is removed, environment/ ecosystem may be destroyed.
Endemic Species
A species that is only found in one country/ island or distinct geographical unit. Ex. lemurs.
Native Species
Occurs naturally somewhere
Invasive Species
Species not native to a specific geographical location. Tend to spread uncontrollably due to lack of predators.
Biodiversity Index
Measures how healthy an ecosystem is. Biodiversity Index= total number of species/ total number of organisms
Species Richness
Refers to numbers of species present in an ecosystem. Wheat fields have a large species richness. Tundra has a low richness.
Species Evenness
Wheat field is not even because of amounts of each species. Tundra has few species, but a good amount of evenness.
Bacteria and Archaea are _________ cells
Prokaryotic
Do prokaryotic cells have a nuclear membrane?
No
How is the DNA in prokaryotic cells stored?
DNA is stored in a circle not strands of chromosomes.
What are the three main shapes of prokaryotic cells?
Coccus: a round shaped cell (ex. Staphylococcus→ staph infections)
Bacillus: a rod-shaped cell. (ex. Lactobacillus→ to digest dairy)
Spirillum: a spiral-shaped cell (ex. Spirillum minus→ from rat bites)
What are antibiotics used for?
Antibiotics are used to kill bacteria by targeting their cell walls.
How do bacteria combat antibiotics?
Bacteria store small circles of DNA called plasmids.
Using a process called horizontal gene transfer, bacteria can give plasmids to other bacteria.
If plasmids contain resistance to antibiotics, new bacteria will also have resistance.
This makes superbugs
Bacteria Evolution
Bacteria quickly adapt.
Rod-shaped pili can extend from one bacteria to another to transfer.
Conjunction and Transformation
A conjunction is a form of sexual reproduction where two bacteria fuse to share DNA.
Transformation is a process where bacteria take in DNA from their environment.
Taking Advantage of Bacteria
Developing drugs and performing research.
We create artificial plasmids and insert them into bacteria to perform different functions.
The production of insulin has been formed by bacteria since 1978.
Bacteria Metabolism
Bacteria can break apart inorganic compounds such as carbon dioxide and produce nutrients.
Bacteria can produce energy through the process of fermentation.
Fermentation is an anaerobic process.
What is a virus?
Virus: a pathogen that consists of 2 parts.
A small strand of DNA or RNA
Protein Capsule
Can infect eukaryotes and prokaryotes
Are not alive→ they cannot replicate without other cells
Measurements: Prokaryotic cells, viruses, viroids, prions
Prokaryotic cells: 200-10,000nm
Viruses: 50-200 nm
Viroids: 5-150 nm
Prion: 2-10nm
How do viruses infect?
- They inject genetic material into a cell.
2. They get eaten by a cell.
Antibodies
Antibodies: proteins produced by immune cells that recognize surface proteins→ viruses
Produced in white blood cells called B Lymphocytes
When infected with virus, white blood cells with eat the virus and secrete antigens to B-cells which produce antibodies.
When a virus tries again, antibodies attach a signal to be eaten.
Vaccines
Designed to make you produce antibodies.
Made of surface proteins from virus or whole virus without DNA.
Body identifies vaccine as a virus to make antibodies.
Anti-Vaccine
If few people aren’t vaccinated, the disease might not spread, but if many people aren’t vaccinated, it can harm the population.
Organelles
Different cells have different organelles.
Amount of organelles present vary on what the cell needs to accomplish.
A muscle cell needs more mitochondria than a skin cell.
White blood cell has way more lysosomes to break down cells.
Organelles determine the function of cell.
Nucleus
Usually the largest organelle.
Contains DNA
Deoxyribonucleic acid (DNA) is a macromolecule made up of a sequence of 4 nucleic acids: Adenine (A), Cytosine (C), Guanine (G), Thymine (T).
Stores how to build proteins.
When DNA is not being “read” it coils with help of the histones found in the nucleolus.
Nuclear envelope has 2 membranes, with pores to transport proteins and RNA.
Endoplasmic Reticulum
Two types: rough and smooth
The rough ER
Thousands of ribosomes in membrane
Synthesises proteins
Membrane-bound ribosomes produce membrane-bound proteins.
The smooth ER
Does not produce→ ships proteins to the Golgi Body.
Produces lipids (___ and steroid hormones).
Detoxifies the cell by metabolizing organic molecules.
Golgi Apparatus (Body, Complex)
Receives proteins and lipids (fat) from ER.
Modifies some and sorts, concentrates and packs them into sealed droplets called vesicles.
Where does the Golgi Body send lipids and proteins?
- Within the cell to the lysosomes,→ animal cells contain lysosomes and it is here that some life expired organelles and other materials are digested.
- Plasma Membrane of the cell→ this group of secretions contribute to the biochemicals of the extracellular matrix, act as chemical signals to other cells, and provide proteins for repair and replacement of the plasma membrane.
- Outside of the cell→ insulin is an example when it is triggered by a rise in blood glucose levels.
What is a lysosome?
Contains digestive enzymes (proteins) that break down molecules.
What are the two types of lysosomes?
- Secretory lysosomes release their enzymes out of the cell to attack viruses, bacteria, or cancer cells.
- Conventional lysosomes digest old proteins that are no longer functioning.
Conventional lysosomes are also responsible for cell apoptosis
Apoptosis is programmed cell death which destroys the cell if it no longer functions properly.
Mitochondria
Contain their own DNA and live in a symbiotic relationship with eukaryotic cell.
Digests sugars and converts them into chemicals called adenosine triphosphate (ATP) → reverse photosynthesis.
ATP is the chemical that provides energy to proteins and allows them to function.
Chloroplasts
Formerly prokaryotes that were absorbed by larger cells.
Where photosynthesis takes place
Chlorophyll converts light into energy and they store that energy in sugar.
Fungi
One of the most abundant organisms
The main decomposers on Earth.
They eat the remains of dead plants and animals.
Pros and Cons of Fungi
Some fungi can cause diseases in plants and animals.
Fungi are used in food production to create foods.
Producers of most antibiotics such as penicillin.
Mushroom is the reproductive organ of the organism.
Fungi can overrule insects brains
Structure
The part that we see is usually the reproductive system.
The body is usually underground.
What is the fungi body made of?
Hypha→ thin filament of cells
Mycelium→ branched mass of hypha
Chitin→ covers the cells and gives the structure.
Reproduction of Fungi
Fungi live most of their life with half a set of chromosomes in the nucleus→ haploids.
When 2 haploid cells come in contact, they form a new cell with 2 haploid nuclei, called a dikaryotic cell.
These dikaryotic cells grow a much larger mature mycelium, which forms the mushroom cap that you are used to seeing.
The gills on the underside of the mushroom produce diploid zygote spores.
Diploid means the nucleus contains 2 sets of chromosomes.
The zygote is a fertilized eukaryotic cell that contains the information to grow the organism.
Spores are like the seeds of fungi.
These spores are released and they grow new fungi.
Plants
Evolved from a group of green algae called charophytes more than 400 million years ago.
Plants share the same chlorophyll molecule with algae.
Over 270,000 plant species
4 Types of Plants
Non-vascular→ Moss
Seedless Vascular Plants→ Ferns
Gymnosperms→ Pine
Angiosperms→ Maple
What stage is an adult plant found in?
An adult plant is found in the diploid stage. Here it is called a sporophyte.
These diploid cells divide by the process of meiosis.
What is meiosis
Meiosis is the process of creating haploid spores (n) containing half a set of chromosomes. These haploid cells will combine with another haploid cell to create diploid zygote (2n).
After meiosis has occurred, asexual spores are produced.
These spores grow into multicellular organisms→ gametophytes
These gametophytes produce haploid sex cells (gametes) which undergo fertilization making zygotes.
Zygotes go on to develop mature plants.
Reproduction in Non-Vascular Plants
These plants have no vascular tissue and they don’t produce leaves, roots or seeds.
The gametophyte generation produces swimming sperm in the antheridium and eggs in the archegonia.
Mosses need to live in moist environments, and they spend most of their life in the gametophyte generation.
Seedless Vascular Plants–> Ferns
Vascular Tissue
Lignin
Pterophytes
Vascular tissue: composed of xylem and phloem. Xylem transports water and phloem transports sugar.
Lignin: a component that gives vascular cells more rigidity and is responsible for the strength of wood.
Pterophytes (ferns) are similar to their ancestors 300 million years ago.
Could grow 40m tall high and 2 metres across.
Reproduction in Ferns
Pterophytes also reproduce with sperm and eggs.
Produces leaves (fronds) and simple stems/ roots called rhizomes→ they grow horizontally underground.
More time in sporophyte generation.
Spores produce gametophytes with sex organs that produce sperm and eggs then they undergo fertilization and produce the diploid plant.
Mature sporophyte grows spore-producing sporangium on the underside of their fronds.
Gymnosperms: Non-flowering plants
First types of seed-producing plants. Coniferous trees. Produce needle-shaped leaves Seeds in cones Cones produce pollen or ovules (female eggs). Seeds contain nutrients for sporophyte. Embryo inside seed coat.
Reproduction in Gymnosperms
Gametophyte life phase of a gymnosperm is short compared to mosses and ferns.
Female shingles are thicker.
Pollan travels through a small tube to fertilize the female.
The fertilized zygote develops into embryo and seed is formed around.
Seeds are dispersed and a new tree grows.
Angiosperms: Flowering Plant
90% of plants
Plants that reproduce sexually using the flower.
Flowers can produce pollen or ovules or both.
Fruit protect and help disperse seeds.
Majority of plant food consumed by humans comes from an angiosperm.
Flowers vary in appearance as do fruit they produce.
Reproduction in Angiosperms
The flower has 4 main parts
1. Calyx: outermost part of the flower which is composed of leafy structures called sepal, they protect an unopened bud.
2. Corolla: composed of colourful petals that attract insects and animals to transport their pollen.
3. Androecium: male reproductive structures that produce pollen in small structures called anthers.
4. Gynoecium: innermost structures in flowers that house the female ovules containing female gametes.
Pollen travels down stigma to fertilize ovules in a seed surrounded by the flesh of a fruit.
Evolution of Animals
700 million years ago, animals developed from protists that were colonies that formed a cavity.
Digestive cavities allowed cells to differentiate from external cells.
1st type of complex animals.
Polyp: one of the 1st types of single cavity animals.
Found in coral
Beginning of Digestion
Cavity became complex and formed a gastrovascular cavity.
Cavity acts as a mouth and an anus
Flatworms have one opening where waste and food go.
Believed that flatworms evolved over time so that a mouth formed. This made the alimentary canal.
Central Nervous System
Spinal Cord
Lacets were ancient fish that were the first species to have a centralized nervous system form on a nerve cord that travels down the centre of the back.
The primitive nervous system allowed animals to move and react to the environment.
Development of vertebrates and invertebrates.
Invertebrates
90% of animals
Have a nervous system, but never developed a vertebra.
Not official taxa, but refers to all animals with no backbone.
Insects, arachnids, molluscs, crustaceans.
Vertebrates
Possess spinal cord with vertebrae bones.
Major classes: Fish, Amphibians, Reptiles, Birds, Mammals (B-Farm)
The more centralized nervous system allowed for the development of complex brains→ allows animals to problem solve.
Characteristics of animals
Animals get energy from aerobic respiration.
Oxygen and food react to produce energy, carbon dioxide and water.
C6H12O6+6O2+6H2O+ATP (Glucose + Oxygen → Carbon Dioxide + Water + Energy)
Animals do not have a cell wall, which allows them to be more mobile and flexible.
Animals can reproduce sexually and asexually.
Asexual Reproduction in Animals
Asexual reproduction does not require the exchange of genetic material with other organisms.
Methods of Asexual Reproduction in Animals
Fission: organism splits itself in two, then regenerates missing parts (anemone).
Budding: a small growth will separate from the parent and grow into mature organisms (cora).
Sexual Reproduction in Animals
Requires female and male gametes to fertilize each other.
Methods of Sexual Reproduction in Animals
Hermaphroditism: when an organism has female and male reproductive organs to self-fertilize.
External Fertilization: when the egg is fertilized after it has left the female.
Internal Fertilization: when the egg is fertilized while still in the female. Fertilized egg either leaves female or matures in the body.
