8B Plant Reproduction

8B Plant Reproduction

• Plants are classified into kingdoms, divided into genus and species for scientific names
• Flowering plants, conifers, ferns and mosses are plant groups
• Vertebrates (mammals, reptiles, fish, amphibians, birds) are animal groups
• Invertebrates (molluscs, arthropods) are animal groups
• Biodiversity is the range of species in an area and should be preserved due to interdependence of organisms and their recovery from disasters.
• Asexual reproduction in plants uses one parent to create offspring via runners (strawberries) or tubers (potatoes)
• Sexual reproduction needs two parents to produce gametes (sex cells). Zygote (fertilized egg cell) will form embryo as part of life cycle
• Offspring from sexual reproduction inherit characteristics from parents (variation)
• Gametes (male and female) are created in reproductive organs inside flowers (anthers, carpel).
• Pollen (male gametes) must be carried to the stigma from anther on another flower (pollination) to form a zygote
• A pollen tube grows from the pollen grain to the ovule with the egg cell within using pollination mechanisms
• Fertilization occurs when the nuclei of the male and female gametes join (zygote)
• The ovule becomes a seed (embryo + food store)
• Fruits aid seed dispersal (e.g. eaten by animals, carried by wind, fur, explosion)
• Seeds need water, oxygen and warmth (WOW) to germinate, starting chemical reactions, to enable the embryo to swell and grow
• New leaves develop, photosynthesis happens in chloroplasts to make glucose (then starch)
• For growth plants need light, air, water, warmth, and nutrients (LAWWN)
• Respiration releases energy from glucose when cells use oxygen to create carbon dioxide and water, using mitochondria
• Sampling is a way to accurately estimate larger population, and a quadrat can be used to sample plants

8F Periodic Table

• Dalton's atomic theory: Atoms are indestructible particles, elements have identical atoms, compounds have fixed combinations of atoms, and during reactions atoms rearrange
• Chemical formulas show the number of atoms in a substance, or ratio of atoms in a compound
• Chemical reactions have reactants and products, with reactants' mass equaling product's mass
• Changes of state are physical changes, where atom numbers do not change, resulting in mass staying the same
• Metals are generally good conductors of heat/electricity with high melting points, strong, malleable and ductile
• Non-metals are generally poor conductors of heat/electricity with low melting points, brittle
• Properties of a substance include chemical (flammability, reactivity) and physical (melting point)
• Mendeleev ordered periodic table by atomic mass, now ordered by atomic number. Similar properties exist in same vertical groups and trends across periods
• Transition metals differ greatly from alkali (react with water) and halogen metals (highly reactive)
• Elements react with oxygen forming oxides, which, based on their type, can be acidic or alkaline
• Elements react with acids in neutralisation reactions, forming salts and water
• Symbols (e.g. N, Li, S, Cu) are single or double letters, where first is capital.

8J Light and Colour

• Light travels in straight lines, transverse waves (faster than sound), doesn't need substance to travel through
• Light passes through transparent objects, not opaque objects
• Shadows are formed when light is blocked, opaque objects block light, translucent objects partially scatter light
• Light is transmitted through transparent materials and absorbed/reflected by opaque surfaces, depending on color. White reflects most light, dark color absorbs most light.
• Reflection occurs at interfaces (e.g., mirrors), where angle of incidence = angle of reflection
• Refraction happens when light hits transparent objects, where speed/direction changes
• Images appear to come from behind a mirror (same size/distance)
• Lenses (curved glass/plastic) refract light in particular ways. Converging lenses bring light rays together, focal point where light rays meet, focal length is dist. from focal point to lens center
• Lenses are found in cameras, microscopes, telescopes
• White light is a combination of colored light. White objects reflect all colors, colored objects reflect some colors and absorb others.
• Color perception is based on the colors reflected (e.g., objects absorb colors besides those we see them as)
• Colors are perceived using filters, which let some colors pass through and absorb others

This quiz covers the key concepts of plant reproduction, including the classification of plants into kingdoms and groups, the processes of asexual and sexual reproduction, and the importance of biodiversity. Test your knowledge on plants' reproductive structures and the life cycle of offspring.