Bioe 20B W5D2 Plant Structure and Function (Oct 31) PDF

REMINDERS ANNOUNCEMENTS 1. Today: Development; Thursday: Start Plants Tuesday, 10/31/24 2. Due Sunday: HW 5, Quiz 5, Figure Summary, Mid-Course Check In Week 5, Day 2 Plant Structure and Function Happy Halloween! TODAY’S AGENDA (8-9:35AM)...

REMINDERS ANNOUNCEMENTS 1. Today: Development; Thursday: Start Plants Tuesday, 10/31/24 2. Due Sunday: HW 5, Quiz 5, Figure Summary, Mid-Course Check In Week 5, Day 2 Plant Structure and Function Happy Halloween! TODAY’S AGENDA (8-9:35AM) Plant Structure and Transport 5 min-break Kahoot!  STUDENT INFO SESSION Thursday, October 31 at 4 PM UC SANTA CRUZ ISB 413 Or every Wednesday at 5 pm PT on Zoom FALL, WINTER, SPRING, AND SUMMER PROGRAMS | EARN 5-15 QUARTER CREDITS Not all classrooms have four walls. INTERNATIONAL ENVIRONMENTAL FIELD PROGRAMS Alaska Big Sur Ecuador Iceland Thailand Australia Chile French Polynesia Nepal Yellowstone Belize Costa Rica Hawaii New Zealand wildlandsstudies.com Academic Partner of Western Washington University Plant Form & Function MORPHOLOGICAL EXTREMES IN NATURE Plant Fun Fact of the Day Monkey face orchids (Dracula simia) found in Ecuador have evolved to attract gnat flies by resembling mushrooms since other pollinators are limited. MORPHOLOGICAL EXTREMES IN NATURE Found in South America Flying duck orchid (Caleana major) native to Australia attracts sawflies  Learning Goals for Today 1 How is plant diversity organized? 2 Plant cells, tissues, organs 3 How tissues are organized in plants 4 Plant meristems, how plants grow, what is wood? REVIEW: How is plant diversity organized? DISCUSS: Why did vascularization evolve in plants? REVIEW: How is plant diversity organized? What’s the difference between monocots and eudicots? Examples: corn, palms, grasses, Cotyledon = onion, wheat, seed embryo ginger, coconut, garlic, orchids, asparagus, pineapple Examples: potato, tomato, rose, eggplant, sunflower, hydrangeas Eudicots have this arrangement to facilitate secondary growth  Learning Goals for Today 1 How is plant diversity organized? 2 Plant cells, tissues, organs 3 How tissues are organized in plants 4 Plant meristems, how plants grow, what is wood? REVIEW: Plant structure and function DISCUSS: What are some KEY DIFFERENCES between animal and plant cells? REVIEW: Plant structure and function DISCUSS: What are the two main parts of a plant and what are their functions? REVIEW: Plant structure and function DISCUSS: What are the two main parts of a plant and what are their functions?  Learning Goals for Today 1 How is plant diversity organized? 2 Plant cells, tissues, organs 3 How tissues are organized in plants 4 Plant meristems, how plants grow, what is wood? 3 Tissues Systems Dermal Tissue Plant Tissues Epidermal cells Guard cells Trichomes (leaf hairs) Root hairs Others Vascular Tracheary elements Tracheids Xylem Vessel elements Sieve tube elements Phloem Companion cells Ground Parenchyma Collenchyma Sclerenchyma fibers sclereids  1. Compare and contrast the 3 plant tissue systems! 2. Make up one quiz question for each tissue type. Dermal Vascular Ground Forms most of plant body Outer covering of Transports water and plant (epidermis) nutrients (plumbing) Function in storage, support and photosynthesis Guard cells open for Xylem transports water gas exchange (dead at maturity) Parenchyma is site of photosynthesis Trichomes (root hairs) Phloem transports sugar (alive at maturity) prevent water loss + (alive at maturity) Support structures: defense against Sclerenchyma herbivores (sclereids + fibers; lignin; dead at maturity) Collenchyma (alive at maturity) Based on the vascular bundle, is this a eudicot or monocot? Eudicot because of the ring-like vascular bundle! A REVIEW: Plant structure and function How do tracheids and vessel elements in xylem differ? Vessel elements transport water more effectively but tracheids also provide rigidity to the plant. REVIEW: Plant structure and function Describe the relationship between sieve tube elements and companion cells in phloem. How do nutrients pass from companion cells to sieve tube elements? Plasmodesmata! Companion cells utilize mitochondria to actively transport sugar in sieve tube elements that are largely free of organelles. REVIEW: Plant structure and function What does it mean for plant cells to be “dead” at maturity? Cells grow to full size and then undergoes apoptosis leaving behind cell wall What are companion cells? What is their role? Phloem cells are composed of sieve tube cells and companion cells; outsource function to companion cells Sieve tube Companion cell What is a meristem? Where are they found? Where cell division occurs; tips of roots/shoots and lateral meristems Leaves 1. What is the function of the cuticle? Prevents desiccation 2. What is the function of the air spaces between spongy mesophyll cells? Allows for gas exchange  What cells are at A? Palisade mesophyll cells A What cells are at B? Spongy mesophyll cells Where does photosynthesis occur? Palisade mesophyll cells (A) B A scanning electron micrograph of a cryo-fractured surface through a leaf lamina of poplar (Populus sp.) showing palisade and spongy mesophyll cells.  5-min Break! Attendance Time Scan the QR code or go to https://tinyurl.com/W5D2plantgrowth to answer the following question: 1) What are the two ways that plants grow? (This will be used for taking attendance today.)  Learning Goals for Today 1 How is plant diversity organized? 2 Plant cells, tissues, organs 3 How tissues are organized in plants 4 Plant meristems, how plants grow, what is wood? Montezuma cypress, "el Árbol del Tule", The Widest Tree in the World, Oaxaca, Mexico Circumference is 42 meters! ~1500 years old REVIEW: How do plants grow? What are the 2 ways that plants grow? Plants make more cells thru cell division Cells expand: Cell elongation/expansion REVIEW: How do plants grow? What are the 2 ways that plants grow? Once meristem makes new cells through cell division All subsequent growth = elongation/expansion Can expand 1000-1,000,000x REVIEW: How do plants grow? What are the 2 ways that plants undergo cell division? Apical meristems Taller/ longer = 1O growth Lateral meristems = 2O growth thickening Vascular Cambium Cork Cambium Root meristems Taller/ = 1O growth longer In your notes… Thought Question R+R A Where will initials B R+R R+R be in 20 years? How do plants grow? Woody Plants develop a secondary plant body Vascular cambium = 1 What is the other of 2 lateral meristems meristem? Makes new xylem and new phloem Xylem on inside, phloem on outside  How do plants grow? Larger xylem = more precipitation What do these Smaller xylem = less precipitation Inner bark Outer bark circles represent? mer sum ring sp oldest Wetter year drier year Growth stops when tree loses leaves in fall (temperate environments) REVIEW: How do plants grow? By yourself: 2 min: draw a picture with bullet points that explains how wood grows How does wood grow? When growth starts in the spring, the Outer Bark vascular cambium undergoes cell division. Cork Cambium (a meristem) Phloem New xylem cells develop inside and new phloem cells develop outside the Vascular Cambium (a meristem) vascular cambium. Xylem  When growth starts in the spring, the Outer Bark vascular cambium undergoes cell division. * Cork Cambium (a meristem) *meristems Phloem New xylem cells develop inside and undergo cell new phloem cells develop outside the division vascular cambium. * Vascular Cambium (a meristem) Xylem Time * * * * * * Vascular cambium makes Cork cambium makes more more xylem on the inside outer cork on the outside and more phloem on the outside Without a dry season, there would be no growth rings! REVIEW: Development Time to review plant structure and function!