science

Cards (14)

  • Adaptations
    • Organisms evolve adaptations over time to better survive in their environment
    • Examples include camouflage in animals to avoid predators and drought-resistant traits in plants
    • Adaptations can be structural (physical features), behavioural (actions), or physiological (internal functions)
  • DNA molecule
    • A double helix structure composed of nucleotides
    • Formed from two complementary strands of nucleotides held together by hydrogen bonds between G-C and A-T base pairs
    • Carries genetic information and instructions for an organism's growth, development, and functioning
    • DNA replication is essential for cells to divide and pass on genetic material to offspring
  • DNA
    • Deoxyribonucleic acid
    • Spiral, sugar, phosphate, base (ATCG: Adenine, Thymine, Cytosine, Guanine)
    • The base is held together by hydrogen bonds
  • Genes and chromosomes
    • Genes are units of heredity that determine specific traits in an organism
    • Chromosomes consist of DNA wrapped around protein structures
    • Genes consist of portions of DNA, DNA consists of nucleotides
    • Chromosomes are structures within cells that contain genes and are passed down from parents to offspring
    • Humans have 23 pairs of chromosomes, with a total of 46 chromosomes
  • Cell division mitosis and meiosis
    1. Mitosis is the process of cell division for growth, repair, and asexual reproduction
    2. During mitosis, a cell duplicates all of its contents, including its chromosomes, and splits to form two identical daughter cells
    3. Meiosis is a process where a single cell divides twice to produce four cells containing half the original amount of genetic information
    4. During meiosis one cell divides twice to form four daughter cells. These four daughter cells only have half the number of chromosomes of the parent cell – they are haploid
    5. Meiosis is a specialised type of cell division that produces gametes (sex cells) with half the chromosome number
    6. Both processes ensure genetic stability and diversity in organisms
    7. The sex chromosomes determine biological sex, with females having two X chromosomes (XX) and males having one X and one Y chromosome (XY)
    8. A karyotype is an image of all of an individual's chromosomes, typically taken during metaphase of cell division
  • Reproduction
    • Reproduction is the biological process by which organisms produce offspring
    • It can be sexual, involving the fusion of gametes from two parents, or asexual, where offspring are genetically identical to the parent
    • Reproductive strategies vary among species based on their environment and life cycle
  • Mutations
    • Mutations are changes in the genetic material (DNA) of an organism
    • They can be caused by errors during DNA replication, exposure to mutagens (e.g., radiation), or environmental factors
    • Mutations can lead to genetic variations, some of which may be beneficial, harmful, or neutral
  • Law of Conservation of energy
    • The law of conservation of energy states that energy cannot be created or destroyed, only transformed from one form to another
    • Energy transfers and transformations occur in various systems, such as chemical reactions, mechanical work, and electrical circuits
    • Understanding this law helps explain energy flow and interactions in the natural world
  • Energy transfers and transformation
    • Energy transfers involve the movement of energy from one system to another
    • Energy transformation occurs when energy changes from one form to another, such as potential energy to kinetic energy
    • Studying energy transfers and transformations helps analyse the efficiency and sustainability of systems
  • Circuit diagrams
  • Series and parallel circuits
    • Series circuits have components connected in a single pathway, where the same current flows through each element
    • Parallel circuits have components connected in multiple pathways, allowing different currents to flow through each element
    • Different circuit configurations affect resistance, voltage, and current distribution in the circuit
  • Current, voltage & Resistance
    • Electric current is the flow of electric charge (usually electrons) through a conductor
    • Voltage is the electrical potential difference that drives current flow in a circuit
    • Resistance is the opposition to current flow in a circuit, determined by the material and dimensions of a conductor
  • Renewables and non-renewable energy

    • Renewable energy sources, like solar and wind power, are replenished naturally and have minimal environmental impact
    • Non-renewable energy sources, such as fossil fuels, are finite and contribute to pollution and climate change
    • Understanding the differences between renewable and non-renewable energy sources is crucial for sustainable energy practices
  • Mitosis and Meiosis
    • Mitosis makes body cells, is the same, and is involved in making new cells
    • Meiosis makes gametes, is haploid, and produces sperm and egg cells