Bio unit1

• Biodiversity is the variety of life on Earth and is essential for human well-being, providing benefits like food, water, shelter, climate regulation, and protection from natural disasters

  
• Biodiversity is linked to ecosystem functions, which provide ecosystem services like food and oxygen from plants, and pollination by animals
• Human activities like climate change and habitat loss threaten biodiversity, making it crucial to protect it by reducing environmental impact and supporting conservation efforts
• Terms related to biodiversity:

  • Ecosystem: all ecosystems in the biosphere
  • Biodiversity hotspot: an area with a high variety of endemic species
  • Endangered species: in danger of becoming extinct in the foreseeable future throughout all or a significant portion of its range

  
• Reasons to study biology:

  • Ecosystem processes are essential for survival

  energy, gases, population balance, pollination

  • Educational and cultural benefits

  species change overtime, recreational purpose for human well being, spiritual life of aboriginal and torres strait islander people, food

  • Contribution to living materials like food, water, air, fiber products, fuels, climate, and pharmaceuticals

  food production, water and air, fiber products, fuels and climate and pharmaceuticals

  • Tourism and economy

  the great barrier reef
• Describing Biodiversity at the 3 levels:

  • Species:
  • Biological species concept: group of organisms that can interbreed and produce fertile offspring
  • Morphological species concept: classifies based on dissimilarities
  • Phylogenetic species concept: uses the smallest group of organisms tracing back to a common ancestor

  
• Ecosystems:

  • Composed of all biotic and abiotic factors in an area
  • Cycling of nutrients is consistent
  • Biotic factors are linked in the transfer of energy (food chains, food webs)

  the ecosystem concept

  relationships between organisms and environment

  Limitations : boundary, cycling on material and movement of some organisms
• Spatial(location) and Temporal(Time) scales of biodiversity:

  • Spatial scales: study extent and distribution of organisms, can range from local to global scales/terrestrial or aquatic ecosystems.
  • Temporal scales: study time frames and scales, monitor population changes, behavioral differences, and extinction rates. It can vary from time frames and scales.
• Australia Biodiversity Conservation Strategy 2010-2030:

  • Context, priorities of action, implementation and action
  • Aims to engage all Australians in biodiversity conservation through mainstreaming, indigenous engagement, and strategic partnerships
  • Seeks to build ecosystem resilience in changing climate to withstand and thrive under changing conditions
• Ecology is the study of interactions between organisms and their physical environment and other organisms
• An ecosystem is an ecological system that includes the organisms in an area (biotic factors) and their physical environment (abiotic factors), and the interactions between these specific factors
• Ecosystems include all the different populations together, such as soil pH value, temperature, light intensity, and the concentration of gases affecting organisms
• Biotic factors affecting an organism include the concentration of gases (H, CO2, N), nutrient availability, competitors, collaborators, predators, parasites, and disease-causing organisms
• Biomes are areas of similar climate, animals, and plants, with examples like aquatic biomes (lakes, oceans, rocky shores, rivers, ponds, coral reefs) characterized by factors like salinity, depth, and nutrient availability
• The distribution of terrestrial environments is due to climate variations, leading to different biomes like tundras, deserts, open forests, and temperate grasslands
• Climate is the atmospheric weather of a specific area averaged over a long period of time, influencing factors like temperature, water, light, and wind, which greatly impact the geographic range of organisms
• Humus - nutrients to the rainforest ecosystem and is a limiting factor for forest growth; more nutritious humus supports more species

  
  

  slow humus producing rate → less nutrient → less species growth
• Substrates are supporting surfaces on which an organism can grow, like rocks, woods, and soil, providing support and nutrients for growth
• Soil analysis includes factors like location, depth, texture, color, porosity, water-carrying capacity, and nutrient status, crucial for understanding the soil's characteristics
• When grown together, P. aurelia out-competes P. caudatum and eventually drives it to extinction

  
• Aquatic environments include marine and freshwater environments, covering 71% of the biosphere, with examples like oceans, lakes, estuaries, creeks, ponds, streams, rivers, and swamps
• Competition:

  • Individuals compete for a resource that limits their survival and reproduction
• Biotic features are tools to classify organisms based on species and interactions, including dominant species like mangroves, further classified by location, and distribution depending on abiotic factors like soil and climate forming particular vegetation patterns.
• Collaboration:

  • Working together to benefit all in a production
• Intraspecific competition examples:

  • Oak trees compete for sunlight
  • Male deers compete for mates and food
• Predation:

  • Balanced population: when the population of prey decreases, there is an increase in predators
• Disease:

  • Disease-causing organisms (bacterial, fungal, viral and the host) affect the balance of an ecosystem and genetic diversity
• Symbiotic Relationships:

  
  

  At least 1 species gets benefited

  • Parasitism: parasite lives on a host, obtaining nutrients and debilitating the host

  -ectoparasites(outside)-lices, ticks

  -endoparasites(inside)-tapeworms, heartworms, hookworms
• Keystone species:

  • A species of relatively low abundance that has a disproportionately large influence over lower trophic levels
  • A species that is used to keep the balance
• Ecological Niches:

  • The way species functions in its environment, including feeding time, shelter, movement, and reproduction times

  (e.g.)

  Humans:

  -People around

  -Food

  -Where you walked
• Fundamental Niches vs. Realised Niches:

  • Fundamental Niche: the potential niche an organism could have without any external limitations

  →no competitors/predators/parasites

  • Realised Niche: narrower in scope and results from an organism's inability to exploit resources from the habitat

  →Species may not be distributed evenly throughout its potential geographic range
• Resource Partitioning:

  • Organisms differentiate in food sources, space, and timing of activities to have better chances of surviving
• Competitive Exclusion Principle:

  • When two similar species compete for the same resources, one will outcompete the other
• Taxonomy is the science of naming, describing, and classifying all living organisms
• Hierarchy of classification:

  1. Domain

  2. Kingdom

  3. Phyla

  4. Class

  5. Order

  6. Family

  7. Genus

  8. Species
• Binomial System:

  • Genetic name + Specific name
  • Genus (capital letter) + species (lower case)
  • Written: underline the name (e.g., Acacia mearnsii)
  • Typed: italicize the name (e.g., Acacia mearnsii)
• Physical characteristics and methods of reproduction are used to classify species
• Molecular sequences are useful when there are fewer morphological differences between species
• Classification of animal phyla:

  • Body plan (symmetry): Radially symmetrical, Bilaterally symmetrical, Asymmetrical
  • Developmental features: DNA sequences, proteins, presence of a gastrovascular cavity, mouth lanes, and developmental layers
• Types of animal phyla:

  1. Porifera (Sponges)

  2. Cnidaria (Jellyfish)

  3. Platyhelminths (Flatworms)

  4. Mollusca (Octopus, squids)

  5. Annelida (Marine worms)

  6. Nematode (Roundworms)

  7. Arthropod (Insects)

  8. Echinodermata (Starfish)

  9. Chordata (class)(Mammals, marsupials, monotremes)