Plant Diversity Lecture 6.1 PDF

Plant Diversity Lecture 6.1 Plant Uses Plants play a central role in human life and society. Food Industry Medicine Advances in science A living bridge, Meghalaya, India A review of Photosynthesis... CQ: What is the correct equation (without the numbe...

Plant Diversity Lecture 6.1 Plant Uses Plants play a central role in human life and society. Food Industry Medicine Advances in science A living bridge, Meghalaya, India A review of Photosynthesis... CQ: What is the correct equation (without the numbers) for PHOTOSYNTHESIS? A. C6H12O6 + O2 + SUN ENERGY → CO2 + H2O B. H2O + CO2 → C6H12O6 C. CO2 + H2O + SUN ENERGY → C6H12O6 + O2 A chloroplast inside a leaf cell. A review of Photosynthesis... CQ: What is the correct equation (without the numbers) for PHOTOSYNTHESIS? A. C6H12O6 + O2 + SUN ENERGY → CO2 + H2O B. H2O + CO2 → C6H12O6 C. CO2 + H2O + SUN ENERGY → C6H12O6 + O2 This is why most autotrophs are green! The chemical, chlorophyll, that absorbs the light energy is also green. A chloroplast inside a leaf cell. Chlorophyll Green pigment that absorbs sunlight. Present in chloroplast organelle of green algae and plants. Remember, green algae are NOT plants, they are protists. … And Cellular Respiration CQ: Which of the following is the correct equation (without numbers) for cellular respiration? A. C6H12O6 + O2 + SUN ENERGY → CO2 + H2O B. C6H12O6 + O2 → CO2 + H2O + ATP (adenosine triphosphate: energy storage molecule) C. C6H12O6 + CO2 → O2 + H2O Cellular respiration in a mitochondria … And Cellular Respiration CQ: Which of the following is the correct equation (without numbers) for cellular respiration? A. C6H12O6 + O2 + SUN ENERGY → CO2 + H2O B. C6H12O6 + O2 → CO2 + H2O + ATP (adenosine triphosphate: energy storage molecule) C. C6H12O6 + CO2 → O2 + H2O Cellular respiration in a mitochondria Which statement best describes the difference between photosynthesis and cellular respiration? A. Photosynthesis only happens in autotrophs, and cellular respiration only happens in heterotrophs. B. Both photosynthesis and cellular respiration happens in autotrophs, whereas only cellular respiration happens in heterotrophs. C. Photosynthesis makes food (carbohydrates) and Cellular Respiration converts the food into usable energy (ATP). D. Cellular Respiration makes food (carbohydrates) and Photosynthesis converts the food into usable energy (ATP). E. Both B and C Which statement best describes the difference between photosynthesis and cellular respiration? A. Photosynthesis only happens in autotrophs, and cellular respiration only happens in heterotrophs. B. Both photosynthesis and cellular respiration happens in autotrophs, whereas only cellular respiration happens in heterotrophs. C. Photosynthesis makes food (carbohydrates) and Cellular Respiration converts the food into usable energy (ATP). D. Cellular Respiration makes food (carbohydrates) and Photosynthesis converts the food into usable energy (ATP). E. Both B and C Origin of land plants from green algae- like ancestor around 500 million years ago.  What differences and similarities do you see (write down)? Green algae Giant Sequoia CQ: What is needed to survive on land rather than in the sea? A. Some way to avoid drying out. B. A way to resist gravity. C. A way to travel through air. D. A way to absorb nutrients from soil rather than water. E. All of the above. CQ: What is needed to survive on land rather than in the sea? A. Some way to avoid drying out. B. A way to resist gravity. C. A way to travel through air. D. A way to absorb nutrients from soil rather than water. E. All of the above. Plant phylogeny Green Algae Moss Ferns Conifers Angiosperms Plant phylogeny What trends do you see? Increasing adaptation to more diverse land environments, especially dry habitats. Plants gain the ability Also roots! - Cuticle/water to get taller. loss prevention; -Chloroplast Spore reproduction. -Multicellularity, tissues Major adaptations of land plants: Vascular tissue Regulate water loss Multicellularity Chloroplast organelle in cells. Roots Seeds Flowers Why is it adaptive for plants to get taller? Which of these plants is getting the most sunlight? Up here? Or down here? Why is it adaptive for plants to get taller? Which of these plants is getting the most sunlight? Up here? Competition for light resource most likely led to the evolution of vascular tissue and lignins, which allowed plants to grow taller and fight gravity. Or down here? Adaptations of plants for land: Water loss prevention Cuticle: waxy covering that is like the “skin” of a plant. Stomata: little mouths on the surfaces of plant leaves that inhale CO2 for photosynthesis. Question: Why not just have a hole that remains open to let in CO2? Why do stomata close? At what time do they open and when do they close? Video of stomata opening and closing: https://www.gettyimages.com/detail/video/microscopic-footage-of-the- stomata-of-a-plant-leaf-stock-video-footage/625489248 Adaptations of plants for land: Fighting gravity Vascular Tissue: Xylem and Phloem move nutrients and water through the plant, against gravity. Major plant traits: Fighting gravity Cell Walls containing Lignin: Cell walls provide support and structure to plant cells. Lignin is the sturdy molecule that makes this possible. Dehydrated plant cell B If a plant cell is placed in a hypertonic solution, water exits the cell, causing the membrane inside the cell wall to shrink away from the cell A wall. Which cell in the photo to the right is dehydrated? (A or B) Dehydrated plant cell B If a plant cell is placed in a hypertonic solution, water exits the cell, causing the membrane inside the cell wall to shrink away from the cell A wall. Which cell in the photo to the right is dehydrated? (A or B)... it is A. Adaptations of plants for land: Finding nutrients on land Roots Roots. Roots allow plants to absorb nutrients (Nitrogen, Phosphorus, others) from the soil. Mutualisms. Roots make mutualisms with mycorrhizal fungi and Fungi Nitrogen fixing bacteria Roots Which of these plant groups can reproduce sexually? Definition of sexual reproduction: Complex form of reproduction in which two individuals produce gametes through meiosis with half the normal chromosome number, and then those gametes fuse (sperm and egg) to form a zygote embryo with the same number of chromosomes as an adult of that species. Which diagram shows sexual reproduction and which shows asexual reproduction? These are dividing cells. Key words: Meiosis Mitosis Gamete Haploid (n) Diploid (2n) Some terminology... Haploid: Cells have only one copy of each chromosome (chromosome number = n). Usually a gamete of the adult organism. Diploid: Cells have two copies of each chromosome. (chromosome number = 2n). Usually the adult, sexually reproducing. CQ: Humans have 23 chromosomes, and 2 copies of each in their cells, for a total of 46 chromosomes per cell. How many chromosomes are there in a human gamete (sperm or egg)? A. 23 chromosomes, 2 of each, total 46. B. 46 chromosomes, 2 of each, total 92. C. 23 chromosomes, 1 of each, total 23. A picture of human chromosomes (a karyotype) CQ: Humans have 23 chromosomes, and 2 copies of each in their cells, for a total of 46 chromosomes per cell. How many chromosomes are there in a human gamete (sperm or egg)? A. 23 chromosomes, 2 of each, total 46. B. 46 chromosomes, 2 of each, total 92. C. 23 chromosomes, 1 of each, total 23. Sperm (23) + Egg (23) = Embryo (46) Sperm (n) + Egg (n) = Embryo (2n) How do plants protect and spread their gametes? Protect the gametes and embryos from drying out! ○ Spores are haploid gametes (n) with a hard coat ○ Seeds are diploid embryos (2n) with a hard coat: Alternation of Generations: Plants have 2 major parts to their reproductive cycle.  Plant groups that evolved later have a more dominant sporophyte generation. In algae and mosses, most of the life cycle is spent as a haploid gametophyte (n). In ferns, about half the time is spent as a haploid gametophyte and half as a diploid sporophyte (2n). In gymnosperms (conifers) and angiosperms (plants with flowers), most of the time is spent as a diploid sporophyte. Which Stage? The gametophyte is always haploid (think of the gametes in meiosis - the plant version of sperm and egg). The sporophyte is always diploid. An example from moss (Phylum Bryophyta): Mosses need moisture to reproduce so their sperm can swim over to an egg!  Key Traits: Moss Reproduces through spores Kingdom Plantae Phylum Bryophyta No vascular tissue or roots Very small I am very Only grows in wet places smol. Dominant gametophyte  Key Traits: Fern Reproduces through spores Kingdom Plantae Has vascular tissue AND roots Phylum Pteridophyta Can get big, but not as big as trees Used to be the dominant land plant on the planet, around 145 mya (Carboniferous).  Key Traits: Reproduces through seeds Has vascular tissue AND roots Conifer Tree Can get very big. The biggest, in fact! Kingdom Plantae Needle-like leaves and cones. Gymnosperms (4 Phyla) Dominant sporophyte (2n) Female Male cone produces Male pollen Female cone is home to egg, is where embryo (seed) forms and is released from. How do giant conifers recover from forest fire? California conifers are fire-adapted. Indigenous peoples of California managed forests with controlled burns to reduce fuel load. Climate change has caused the fires to increase in intensity to the point where the tree’s adaptations may not be enough Fire ecology and tree adaptations to fire Thick bark. Fire-induced sprouting and extensive underground root systems. Serotinous cones. Fire-activated seeds.  Key Traits: Reproduces through flowers and seeds Has vascular tissue AND roots Angiosperms Most of the world’s crops are Kingdom Plantae Angiosperms. Phylum Anthophyta Assignments Textbook readings: Ch. 29 (all), and 30.1-30.2