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Grade 11 Diversity SBI3U
Bactria
Prokaryotes
Small cells
DNA is circular and not enclosed in a nucleus
Reproduce through binary fission (asexual reproduction)
Mostly unicellular
Many are anaerobic (do not require oxygen)
Eukaryotes
Larger cells, DNA enclosed in a nucleus
Possess many chromosomes
Reproduce sexually
Most are multicellular
Contain many organelles
Most are aerobic (require oxygen)
Importance of Bacteria
Not all bacteria are pathogenic (harmful)
Help with food production and chemical processes (e.g., nitrogen fixing for plants)
Contribute significantly to oxygen production
Cyanobacteria initiated photosynthesis, which transformed Earth’s atmosphere and enabled the oxygen-rich environment we depend on today.
Types of Bacteria:
Thermophiles: Prefer high temperatures (heat).
Methanogens: Utilize carbon dioxide (CO₂) and hydrogen (H₂) to produce methane (CH₄).
Halophiles: Thrive in salty environments.
Know how to label this
Asexual Reproduction in Bacteria
Asexual reproduction is a fast process that does not require a partner.
However, mistakes can occur during DNA duplication, leading to mutations. These mutations can be either harmful or beneficial.
Genetic Recombination
Genetic recombination mixes genetic material, resulting in variations rather than clones.
Clones can be problematic because if one clone is affected by disease, it can wipe out the entire population.
Methods of DNA Change
Bacteria can change their DNA through several methods:
Mutation: Random changes in DNA.
Conjugation: A process similar to sexual reproduction where genetic material is exchanged between two bacteria.
Transformation: Bacteria can take up dead DNA from their surroundings.
Transduction: Viruses can carry DNA from one bacterium to another, facilitating genetic transfer.
Classifying Bacteria
Bacteria can be classified by:
Shape
Cell walls
Sources of food
Energy sources
Genetic analysis
Shapes of Bacteria
Cocci: Round, ball-shaped bacteria.
Bacilli: Rod-shaped bacteria.
Spiral: Bacteria in spiral form.
Gram Staining
Gram staining determines whether bacteria absorb a particular stain.
Gram Positive: Bacteria that absorb the stain and appear purple.
Gram Negative: Bacteria that do not absorb the stain and appear pink.
fungi
Fungi Overview
Characteristics
Multicellular, eukaryotic organisms
Many nuclei for cell function
Cell wall made of chitin
Grow in shady, moist environments
Digest externally with enzymes
Cannot move
Heterotrophs: Fungi cannot produce their own food and rely on other organisms for nutrients.
The Good
Decomposers: Fungi recycle dead material, converting complex substances into raw materials for plant and fungi growth.
Food Production: They are used in making alcohol and bread.
Medical Uses: Fungi are sources of important medical compounds like penicillin.
Medical Importance
Penicillin: Discovered by Alexander Fleming, mold restricted the growth of bacteria, leading to the development of penicillin.
Cyclosporin: A drug that helps prevent organ rejection in transplants by targeting T cells.
The Bad
Some wild fungi are poisonous and can affect the nervous system. Generally, brighter fungi tend to be more poisonous.
The Ugly
Athlete's Foot: A fungal mold from dirty shoes or showers; it can be treated with powder or cream.
Ringworm: A skin infection caused by fungus, characterized by itching.
Classification
Fungi were historically classified as plants.
Fungi Structure
Nutrient Absorption: Occurs in mycelium, composed of filaments called hyphae (plural: hyphae).
Above Ground Structures
Scales: Small dots that cover and protect the mushroom.
Cap: The top of the mushroom, which protects the spores.
Gills: Located under the cap, they contain spores.
Stalk: Supports the mushroom above ground.
Below Ground Structures
Mycelium: Comparable to roots, it consists of branches of hyphae.
Hyphae: Larger branches that absorb nutrients.
Reproduction in Fungi
Spore: A reproductive cell similar to a sperm cell.
Asexual Reproduction: Mycelium can break apart by fragmentation.
Sexual Reproduction: Mycelium from two different fungi can combine to form new fungi.
Fungal Partnerships - Symbiosis
Lichens: Obtain sugar from photosynthesis and provide algae/cyanobacteria with nutrients (carbon dioxide, water). Important as the first organisms on rocks.
Mycorrhizae: Networks of hyphae that help plants absorb nutrients while receiving sugars from the plants. Some plant seeds cannot germinate without the presence of mycorrhizal fungi.
What is our system for naming things?
System for Naming Organisms
Importance of Naming: Naming organisms helps in identifying medical edible plants, determining infections for treatment, and assisting farmers in knowing their crops. It also clarifies how to tell if organisms belong to the same species.
Taxonomy: Linnaeus initiated the system of taxonomy, which is used to classify and name organisms.
Scientific Naming Conventions:
Format: The scientific name follows this structure: Genus name (capitalized) species name (lowercase).
Example: The tiger is called Panthera tigris.
Subspecies: There is an additional classification for subspecies, such as the wolf as Canis lupus and the dog as Canis lupus familiaris.
Species Definition: A species is defined by the capability of its members to produce fertile offspring.
Taxonomic Categories (Taxa):
The taxonomic hierarchy is organized as follows, from the most broad to the most specific:
Domain
Kingdom
Phylum
Class
Order
Family
Genus
Species
A mnemonic to remember this is: Dude Keep Pond Clean Or Froggy Gets Sick.
Methods of Identification: To identify organisms, scientists consider:
Anatomical structures: The physical structure of organisms.
Physiological data: The functions and processes of organisms.
DNA: Genetic information is crucial for classification and identification.
Animal
Criteria to Classify Animals
Presence of Backbone: Animals can be categorized based on whether they have a backbone (vertebrates) or not (invertebrates).
Movement: Some animals are mobile, while others are stationary.
Complexity of Organs and Tissues: Animals vary in the complexity of their organ and tissue structures.
Symmetry: Animals can be classified by their body symmetry:
Asymmetrical: No symmetry.
Bilateral Symmetry: Symmetrical along one plane.
Radial Symmetry: Symmetrical in multiple planes.
Reproduction: Most animals reproduce sexually (about 99%), with very few reproducing asexually. Reproductive methods include:
Internal Fertilization: Sperm enters the female.
External Fertilization: Eggs are laid and fertilized outside the female.
Characteristics of Mammals
Hair/Fur: Mammals have hair, with the exception of one species (the monotreme).
Reproduction: Mammals give live birth, except for a few that lay eggs.
Mammalia Traits:
Produce milk to nourish their young.
Have hair or fur.
Possess four-chambered hearts.
Have highly developed brains.
Protists
Endosymbiosis
Definition: Symbiosis means a mutually beneficial relationship between two parties. In endosymbiosis, a larger cell engulfs a smaller cell, allowing both to survive and work together. This process leads to the formation of chloroplasts and mitochondria.
Three Main Branches of Protists:
Plant-like Protists:
Phytoplankton
Diatoms: Cell walls made of silica.
Dinoflagellates: Can cause toxic "red tides."
Euglenoids: Autotrophs during the day and heterotrophs in the dark.
Animal-like Protists (Protozoans):
Have features such as:
Flagella: tail-like structures.
Cilia: tiny hair-like structures.
Pseudopods: false feet for movement.
Fungus-like Protists:
Heterotrophic and act as decomposers.
Different from fungi because they are not made of chitin and can be unicellular or multicellular.
Multicellularity in Protists:
Algae is a protist but is not as complex as tissues in multicellular organisms.
Reproduction:
Protists can reproduce both asexually and sexually, with some species capable of both.
Advantages of Protists:
Plant-like protists are the base of the marine food chain.
Some are edible and used in foods such as sushi.
Disadvantages of Protists:
Certain diseases, like malaria, are caused by protozoa.
Dinoflagellates can lead to harmful red tides.
Antibiotics/vaccines
bioremediation can be use to help fix oil spoil because the Bactria s the oil
ANTIBIOTIC
Antibiotic:
don’t work on viruses only Bactria cells
often made from fungus, but now possible to be made without fungus
usually taken in pill form but can be has eye/ear drops or swab
can use preventative antibiotics if- Big surgery NORMALLY DON’T
Life before Antibiotics:
A lot kills, Strep throat, ear infections, sits,moms and baby often died during child birth
blood leching is when they cut you and let the blood out
leaching use leach to take blood out of you
Fleming: discovered penicillin
Types of Antibitocs:
Broad spectrum: eg: amoxicillin effective on most bacteria, used when happens but source is unknown, risks damaging important bacteria or antibiotic resistance
narrow spectrum, only effective against a specific bacteria
improperly use of antibiotics
MUST finish antibiotic course because it kills the weaker ones first,and you feel better but the strong ones take over
when more resistant ones stay the strong ones reproduce making the bacteria more powerful.
Vaccines
vaccines:
can PREVENT viral diseases
are a dead or weak form of virus ( same shape but cant cause sick)
immune system reacts by producing antibodies that match the shape
Gives heads up to immune system so it remembers the shape
Jenner, vaccine small pox
Salk, made dead virus so you don’t have to get sick
Viruses
Viruses are considered non-living entities.
They do not have cells, which distinguishes them from living organisms.
The main protective structure of a virus is called a capsid, which is a protein coat that surrounds the virus.
Additionally, viruses have small structures called antigens. These antigens act like little flags that help the virus identify and attach to its host cell.
some viruses can create an envelope: part of the host cell membrane warps around virus
Memorize basic structure here: left side DNA, antigen(little flags on circle) and Capsid right side DNA and Cuspid(head)
example of human viral
Organism: diseases retroviruses ( HIV )
diseases: AIDS and some cancers
transmission: direct contact
Epidemic: is a disses in small area, for example Durham
pandemic: is a disses in large area, for example it crosses the border
the lytic cycle vs lysogenic cycle
Plantae
Overview of Plants
Types of Plants
Autotrophs: Organisms that make their own food.
Multicellular: Plants are made of multiple cells.
Reproduction: Can reproduce sexually or asexually.
Habitat: Most plants are terrestrial.
Vascular vs Non-Vascular: Main difference is the presence or absence of vascular tissues and seeds.
Non-Vascular Plants (Bryophytes)
Characteristics: Old, low-growing, no roots (rhizoids), and reproduce by spores.
Examples: Mosses, liverworts, hornworts.
Transport Mechanism: Use diffusion and osmosis, lack vascular tissues (xylem and phloem).
Seedless Vascular Plants (e.g., Ferns)
Characteristics: Have both xylem and phloem, allowing for tall growth.
Xylem: Transports water.
Phloem: Transports sugars from leaves.
Reproduction: Reproduce by spores.
Seed-Producing Vascular Plants
Gymnosperms
Examples: Pine cones, spruce trees.
Characteristics: Seeds on cone scales, "naked seeds" not covered by fruit, mostly evergreen.
Angiosperms
Examples: Roses, maple trees, grasses.
Characteristics: Flowering plants, seeds in fruit, most successful group with 250,000 known species.
Flower Structure
Features: Colorful and aromatic to attract pollinators (e.g., bees).
Pollination: Some plants are male, some female, and many are both. The fruit is the ovary containing seeds.
Evolutionary Adaptations of Plants
Waxy Cuticle: Prevents water loss.
Stomata: For gas exchange.
Vascular Tissues: Xylem and phloem for transport.
Lignin: Provides structural support for tall growth.
Seeds: Allows reproduction in dry environments, stores nutrients for growth.
Pollen: Enables fertilization without water.
Angiosperm Classification
Monocots: One cotyledon, leaves with parallel veins (e.g., corn, onions, grass).
Dicots: Two cotyledons, leaves with branched veins (e.g., maple, beans, dandelions).
