Biology

• Endocrine System


  • Regulates long term changes in the body such as growth and development
  • Controls many of the body's daily activities
• Endocrine Glands


  • Group of organs that produce and release chemical substances that signal changes in other parts of the body
  • Directly releases substances into the bloodstream
• Hormones


  Chemical substances produced by an endocrine gland
• Hormones


  • Adrenaline: directs response to sudden stress or fear
  • Testosterone: controls beard growth in males
  • Growth hormone: makes you grow to adult height
• Endocrine Glands


  • Thyroid Gland
  • Parathyroid Gland
  • Pancreas
  • Hypothalamus
  • Pituitary Gland
  • Thymus gland
  • Adrenal gland
  • Ovaries
  • Testes
• Function of Endocrine Glands

  • Thyroid Gland: control overall metabolic rate and calcium levels
  • Parathyroid Gland: regulates calcium and phosphorus levels
  • Pancreas: controls sugar level in the blood
  • Hypothalamus: links endocrine and nervous system, controls pituitary functions
  • Pituitary Gland: controls other endocrine glands, regulates growth, reproduction, metabolism
  • Thymus gland: helps immune system develop
  • Adrenal gland: release hormones, respond to sudden stress
  • Ovaries: release sex hormones, control female body changes at puberty
  • Testes: release sex hormones, control male body changes at puberty
• Reproduction


  Process that continues life on Earth
• Reproductive System


  Collection of organs involved in sexual reproduction
• Male Reproductive System


  • Penis: delivers sperm and urine
  • Scrotum: holds and protects testes
  • Sperm Duct: tube for mature sperm
  • Seminal Vesicle: provides sperm with fluid
  • Prostate Gland: provides alkaline fluid to activate sperm
  • Cowper/Bulbourethral Gland: produces fluid for urethra
• Menstrual Cycle


  • Maturing of an egg
  • Production of female sex hormones
  • Preparation of uterus to receive fertilized egg
• Phases of Menstrual Cycle

  • Phase 1: Menstrual flow begins
  • Phase 2: Uterine lining thickens, ovulation occurs
  • Phase 3: Uterine lining continues to thicken
• Menopause


  Time when ovulation and menstruation ends
• Biosphere


  Region on Earth that contains all living organisms
• Earth Spheres


  • Biosphere
  • Atmosphere
  • Hydrosphere
  • Lithosphere
• Abiotic Factors


  Nonliving, physical features of the environment
• Water


  • Makes up 50-95% of most organisms' bodies
  • Important for respiration, photosynthesis, digestion, and other life processes
• Soil


  • Combination of sand, clay, and humus
  • Humus is decayed remains of dead organisms
• Light and Temperature


  • Impact the environment
  • Sunlight energy is converted to chemical energy in food molecules through photosynthesis, driving life's processes
• Biotic Factors


  Living or once living organisms in the environment
• Levels of Biological Organisation

  • Chemical Level: atoms form molecules, macromolecules
  • Cellular Level: molecules form organelles that perform cell functions
  • Tissues: group of cells doing the same work
  • Organs: different tissues working together
  • Organ Systems: groups of organs working together
  • Organisms: any living thing that can live on its own
  • Populations: group of same species living and reproducing together
  • Communities: populations of different species interacting
  • Ecosystems: biotic communities and abiotic factors
  • Biosphere: all communities on Earth
• Population Characteristics


  • Population Sizing: number of individuals
  • Population Spacing: clumped, random, uniform
  • Population Density: individuals per unit area
• Limiting Factors


  Living or non-living features of the environment that restrict population size
• Carrying Capacity


  Maximum population size the environment can support long-term
• Types of Symbiosis


  • Mutualism: benefits both species
  • Commensalism: benefits one, doesn't harm other
  • Parasitism: benefits parasite, harms host
• Niche


  Role of an organism in the ecosystem
• Producer


  Organism that makes its own food by photosynthesis, first feeding link
• Autotroph


  Organism that collects energy from sunlight or inorganic substances to produce food
• Heterotroph


  Organism that gets energy by consuming other organisms
• Food Chain


  Simple model showing how energy flows through an ecosystem
• Food Web


  Interconnected food chains at multiple trophic levels
• Ecological Pyramids


  Models showing energy, biomass, and number of organisms at each trophic level
• Detritivore


  Organism that eats fragments of dead matter in an ecosystem
• Law of Conservation of Mass and Energy

  Matter is never lost or gained, it is recycled
• Water Cycle


  1. Evaporation

  2. Condensation

  3. Precipitation
• Water cycle happens because the energy from the sun causes water to evaporate and rise into the atmosphere
• Carbon Cycle


  1. Plants remove carbon from air and use it to make carbohydrates

  2. Carbohydrates are used by other organisms

  3. Carbon is returned to atmosphere through respiration, combustion, erosion, and decomposition
• Nitrogen Cycle


  Transfer of nitrogen from atmosphere to plants and back again
• Water cycle


  Water on the surface of the Earth evaporates and rises into the atmosphere as water vapor
• Water cycle is an important process because it enables the availability of water for all living organisms and regulates the weather patterns on Earth
• If water didn't naturally recycle itself we would run out of clean water