BL1004 PPTlectures1-3 (2024-2025) Plant & Animal Physiology PDF

Physiology of Plants and Animals BL1004 Prof. Marcel Jansen, Plant & Environmental Sciences, BEES, Enterprise Centre, Distillery Field [email protected] 1  Staff  Prof Marcel Jansen  Module co...

Physiology of Plants and Animals BL1004 Prof. Marcel Jansen, Plant & Environmental Sciences, BEES, Enterprise Centre, Distillery Field [email protected] 1  Staff  Prof Marcel Jansen  Module coordinator  Lecturer plant physiology – 8 lectures  Prof Rob McAllen, Dr Fidelma Butler, Prof Sarah Culloty & Dr Neil Coughlan  Lecturers animal physiology – 9 lectures  Dr Tom Quirke  Coordinator 2 practicals  [email protected] 2  Lectures See timetable on canvas Group 1: Biological and Chemical Sciences Group 2: Food Science and Technology, Nutritional Sciences, Geography and Archaeology, Biological, Earth and Environmental Sciences You can swap between groups but be aware of slightly divergent timetables! For practicals; await communication Dr Tom Quirke 3  How to study for BL1004?  Campbell & Reece (ed. 9, 10, 11, 12 …….) . . . 4  How to study for BL1004?  Campbell & Reece (ed. 9, 10, 11,12 …….)  Lectures . . 5  How to study for BL1004?  Campbell & Reece  Lectures  PPT’s on Canvas  Annotate slides  Make notes vs slide numbers 6  How to study for BL1004?  Campbell & Reece  Lectures  PPT’s on Canvas What works best for you?! 7  How to study for BL1004?  Campbell & Reece  Lectures  PPT’s on Canvas  Practicals obligatory 8  BL1004 marks  Practical Plant Physiology = 15%  Practical Animal Physiology = 15%  Winter MCQ exam = 70% In case of absence from practicals, an “absence form has to be completed” Queries “[email protected]” 9 Plant physiology 10 Plants; what plants …..? Plant blindness! Luke Skywalker on the look-out for plants??? 11  Plants; lots of them …..! Plant biomass dominates total biomass on the Earth (450 Gt out of a total of ≈550 Gt) Gt = Gigatonne Yinon M. Bar-On, Rob Phillips, and Ron Milo PNAS June 19, 2018 = billion tonne = 109 tonne 12 Why are plants relevant? Some of the key challenges of our time: Climate change Sustainability and resources Food supply Biodiversity Pollution 13  Why study plants? e s ng lle ha Some of the key challenges of our c time: s e h e Climate change l t al ng i Sustainability and resources s e s d r Food supplyad in a l r Biodiversity t e n c s t Pollution an Pl 14 A bit of history; why study plants?  Phytochemicals / medicine Ascorbate = vitamin C Scurvy Vitamin C- deficiency 15  A bit of history; why study plants?  Medicine / phytochemicals Orto Botanico di Padova University Padua Founded in 1545, it is the world's oldest academic botanical garden 16 A bit of history; why study plants?  Medicine / phytochemicals Dioscorides 50-70 AD Greek in the Roman army  De Materia Medica  Detailed pharmacological uses of plants  Remained most important reference work till the late 1600’s 17 A bit of history; why study plants?  Medicine / phytochemicals Culpeper 1616-1654  Complete Herbal  Detailed pharmacological uses of plants 18  Modern history; why study plants?  Food (quantity / quality) 19 FAO Statistical Yearbook 2021  Modern history; why study plants? Four global crops—maize, rice, wheat, and soybean—produce nearly two-thirds of global agricultural calories To accommodate population growth, and increased demands for food, production needs to double by 2050 Yields for the top four crops are increasing at 1.6%, 1.0%, 0.9%, and 1.3% per year, respectively, which is far less than the 2.4% per year rate required to double global production by 2050 Furthermore, recent projections indicate that crop yields will actually decrease under future climate conditions Ray, D.K., Mueller, N.D., West, P.C. and Foley, J.A., 2013. Yield trends are insufficient to double global crop production by 2050. PloS one, 8(6), p.e66428. Modern history; why study plants?  Food (quantity / quality)  sustainability? 21 FAO Statistical Yearbook 2021  Bottle; 30% plant polymers Why study plants?  Medicine / phytochemicals  Food (quantity / quality)  Materials (fibers / polymers)  Energy (oil, sugars, wood) 22  Why study plants?  Medicine / phytochemicals  Food (quantity / quality)  Materials (fibers / polymers) Inspiration  Energy (oil, sugars, wood) Inspiration = Biomimicry Galium aparine; cleavers or sticky willy Velcro 23  Why study plants?  Medicine / phytochemicals  Food (quantity / quality)  Materials (fibers / polymers) Inspiration  Energy (oil, sugars, wood) Inspiration = Biomimicry Self-cleansing Lotus with super-hydrophobic, self-cleansing surface paint 24  Why study plants?  Medicine / phytochemicals  Food (quantity / quality)  Materials (fibers / polymers)  Energy (oil, sugars, wood)  Bio-remediation (fish waste is a resource for growth duckweed (Lemna)) Mt Lucas fish-farm (Offaly) with Lemna- water remediation 25  Plants and bio-remediation In the UK alone, 1,900 deaths are averted each year through absorption of air pollution by vegetation Data RHS 2019 26  Why study plants? Plants and horticulture as a central component of strategies to deal with: Obesity Social Isolation Mental Health Issues 27  Why study plants?  Medicine / phytochemicals  Food  Materials  Energy  Bio-remediation  Carbon sinks  Human health  Social policy  Crucial components ecosystems 28  What is different about plants?  Plant structure  Photosynthesis  Nutrition and internal transport  Phytohormones  (Reproduction) 29  Lectures on plant structure Campbell & Reece (ed. 8) Chapter 35, overview plus concepts 35.1 - 35.4 Campbell & Reece (ed. 9) Chapter 35, overview plus concepts 35.1 - 35.4 Campbell & Reece (ed. 10) Chapter 35, intro plus concepts 35.1 - 35.4 30  Plant structure  Molecular structure DNA, proteins and lipids  Chemical composition  Folding / Conformation 31  Plant structure  Cellular structure (cytology) 32  The plant cell  Chloroplast  Amyloplast  Vacuole  Cell wall  Plasmodesmata 33  Plant structure  Tissue structure (histology)  Group of cells with same function and/or structure Epidermis tissue 34  Plant structure  Organ  Collection of tissues that together carry out a particular function  Root, stem and leaf Leaf 35  Plant structure  Structure of the whole plant (anatomy)  Organisation tissues and organs inside organism  Structure of the whole plant (morphology)  Outward appearance (shape, structure) 36 Aquascaping world  Plant structure  Vegetation structure (ecology) Calcareous semi-natural grassland, Roscommon (BEC-consultants) 37  The function of structure? The importance of controlling the pH within a cell Enzyme activity pH 4 pH 7.5 pH Enzyme 1 Enzyme 2 Can both enzymes work simultaneously? 38  Dogma structure - function At all organisational levels close interactions between structure & function 39 Examples link structure - function  Structure nucleus is to protect DNA  Structure chloroplast enables photosynthesis  Peroxisomes are distinct structures for oxidative metabolism  Glyoxisomes distinct structures for lipid metabolism 40  Examples link structure – function 2 At all organisational levels there are close interactions between structure and function Large specific area, to capture light Thin, elongated structure that can push between soil particles 41  Why study plant structure?  To understand function 42  Why study plant structure?  To understand function  Exception taxonomy (identifying, grouping & naming organisms) Theophrastus 300 BC  Father of botany  Historia de Plantis  4 taxonomic groups; trees, shrubs, under-shrubs, herbs 43  Why study plant structure?  To understand function  Taxonomy (identifying, grouping & naming organisms) Carl von Linné (1707-1778)  Species plantarum  Start of binomial nomenclature “genus and species” 44  Determinants of plant structure 1  Plants that share an ancestor will share morphological features  Homology; when traits in different species exist as a result of an inherited (ancestral) genetic feature Homologous structures 45  Determinants of plant structure 2  Plants that share an ancestor will share morphological features  Evolutionary history 46  Determinants of plant structure 2  Plants that have been exposed to the same selective pressures by the environment will share morphological features  Genetic adaptation (natural selection)  Convergent evolution  Evolution of similar features due to similar environmental pressures  Analogous trait - similarities between organisms not present in a common ancestor 47  Convergent evolution – spikes to protect from herbivores (analogous trait) Holly- spikes from leaf edge Hawthorn – spikes from branch Cactus – spike whole leaf 48  Convergent evolution A cactus, Astrophytum asterias A spurge, Euphorbia obesa No leaf surface area to reduce water loss - Stem for photosynthesis Analogous traits - similarities between organisms not present in the last common ancestor 49  Determinants of plant structure 3  Plasticity; the ability of an individual plant to adjust structure to local environment Effect wind (mechanical stress) (a) Exposed (b) Control 50  Determinants of plant structure 3  Plasticity; the ability of an individual plant to adjust structure to local environment Ranunculus sp. Heterophylly  Within organism, in principle, all cells are genetically identical  Underwater leaves “streamlined”  Surface leaves for flotation 51 Plasticity more common in plants than animals Primula veris; 3 or many flowers/stalk Dog with six legs 52 Plasticity more common in plants than animals  Tree adjusted to growing upside down ↑ Dog adjusted to Tree grazing adjusted to leaves from prevailing trees wind 53 Plasticity more common in plants than animals Kenmare Abbeyleix Lismore The wonderful world of wonky trees; plasticity!!! 54 Plasticity more common in plants than animals Tinahely (wicklow) 55 Why is plasticity more common in plants?  Plants are sessile  Animals are mostly mobile  Plants need to adjust to local (unfavourable) conditions 56  Determinants of plant structure  Genetic background  Ancestry  Genetic adaptation / selection  Environmental plasticity Massive structural variation 57 Number crunching…..!  Mosses and related sp 25.000  Ferns and related sp. 14.000  Gymnosperms 900  Angiosperms 250.000 (including all major crop species) 58  Three plant organs Dilemma of living in two distinct environments Solution: root system versus shoot system Three plant organs: Roots, stems and leaves Organ: specialised part of plant body made up of tissues 59  Three plant tissues Four according to leaving cert!  Tissue: group of cells with common structure and function  Dermal tissue  single layer  epidermis  Vascular tissue  Xylem  phloem  Ground tissue  Parenchyma  (Meristematic tissue)  Meristems 60  Dolly the Sheep 1996-2003 Plant tissues  Plant cells are totipotent: all cells can de-differentiate, divide and develop into complete new organism (unlike animal cells)  Part of environmental plasticity plants nucleus from an adult cell transferred into unfertilised oocyte 61  Dolly the Sheep Plant tissues Animals Unipotent cell, can develop in just one type of tissue Pluripotent (stem) cell can develop into different tissues, but not a whole organism But technological advances …….! 62 The three organs Root Stem Leaf 63  Three organs? What about flowers? Sepals and petals look like leaves and are leaves The male stamen & female carpel are in essence rolled up leaves 64 Three organs? What about flowers? Leaves can also colour (developmental disruption) RHS July 2023 65 Leaves  Photosynthesis  Reproduction 66  Modified leaves Storage - onion Spine Tendril 67 Leaf structure 68 Leaf structure  Epidermis  Waxy cuticle  Stomata  Trichomes (hairs) 69 Leaf structure  Epidermis  Waxy cuticle  Stomata  Trichomes  Mesophyll  Palisade mesophyll  Spongy mesophyll 70 Leaf structure  Epidermis  Waxy cuticle  Stomata  Trichomes  Mesophyll  Palisade mesophyll  Spongy mesophyll  Vascular system (vein)  Phloem transport sugars  Xylem transport water  Surrounded by a protective circle of cells, the bundle sheath 71  Stems Carries leaves and “positions” these in the light Control stem length – strategy Connection root - leaf 72  Modified stems Phylloclade, Photosynthetic stem Rhizome, horizontal underground stem Stem tuber (potato) 73  Structure stem  Apex - bud with meristem  Node & internode  Axillary buds 74  Axillary buds Axillary buds mostly dormant Apical dominance 75  Axillary buds Axillary buds mostly dormant Process named “Apical dominance” Apex inhibits growth axillary buds Evolutionary adaptation to reach out for light 76  Axillary buds Sprouting axillary bud yields lateral shoot Lateral shoot carries secondary apex and (dormant) secondary axillary buds 77  What happens if there is no apical dominance? Witch broom 78 Stem structure 79 Stem structure  Epidermis  Ground tissue  Pith in centre  Cortex outside from vascular bundles  Fibres  Vascular tissue  Locatedjust behind epidermis (!)  Phloem outside / xylem inside 80 Stem structure 2 81 Stem structure 2 Fibers Collenchyma – in young tissue – living & flexible Sclerenchyma – in mature tissue – dead & rigid 82 Sclerenchyma cells - linen 83 Sclerenchyma cells - hemp 84  Roots  Anchor, uptake water and minerals, storage, photosynthesis Adventitious root  Taproot versus fibrous root system  Lateral roots from main root  Adventitious roots from stem Tap vs fibrous 85  Roots Biomimicry buttress church Mangrove lateral air roots pneumatophores Mangrove – adventitious prop roots for support Prevent erosion / land builders 86  Roots Ivy adventitious (aerial) roots for climbing support 87 Roots Adventitious aerial roots Ficus sp. 88  Photosynthetic root Roots Photosynthesis can take place in:  Leaves (most common)  Stems (phylloclade)  Roots Plasticity plants!!!!!! American ghost orchids (Dendrophylax lindenii) 89  Roots Haustorial root of parasitic mistletoe 90  Roots as part of ecosystems Mycorrhiza – mutually beneficial networks of plant and fungi Root with nitrogen fixating nodules 91 Root structures Lateral root Root hair zone (maturation) o ne n z o gati elon o ot R (div is io n zone) Meristem Root cap (protection) 92 Root hairs and lateral roots  Root hair = extension of epidermal cell (increased uptake surface)  Lateral root = multicellular root 93 Root structures 1 94 Root structures 1  Epidermis 95 Root structures 1  Epidermis  Vascular tissue  Locatedin centre root (!)  Phloem outside / xylem inside 96 Root structures 1  Epidermis  Ground tissue  Pithin centre (or absent)  Cortex outside from vascular bundles  Vascular tissue  Locatedin centre root (!)  Phloem outside / xylem inside 97 Root structures 1 98 Root structures 2  Endodermis – inner layer cortex  Controls nutrient uptake  Pericycle  Can become meristematic  Forms lateral root 99 Lateral root formation Pericycle 100  Lateral roots and shoots Lateral shoots pre-formed (axillary buds) Dormancy axillary buds controlled by apex Located near surface stem (near vascular system) -------------------------------- Lateral roots not-preformed Located deep inside (near vascular system) 101  Lateral roots and shoots Lateral shoots pre-formed (axillary buds) Dormancy axillary buds controlled by apex Located near surface stem (near vascular system) -------------------------------- Lateral roots not-preformed Located deep inside (near vascular system) 102  The position of the vascular system Stem Strength & connections buds and leaves Root Nutrient absorption The vascular system changes from a single cylinder in the root into a dissected cylinder of vascular bundles in the stem. 103 How do plants grow?  Primary growth  Lateral growth (lateral roots/shoots)  Secondary growth 104 Primary growth Newly formed leaves Meristem Axillary buds 105 Primary growth Two processes are responsible for primary growth 1)Cell division (mitosis) 2)Cell enlargement These are followed by cell differentiation 106  Primary growth Mitosis in meristems in root and stem apex and in axillary buds Meristems contain embryonic cells Cell division in meristems yields : Initials (remain in meristem) Derivatives (will differentiate) 107  Primary growth Indeterminate growth stem and roots Determinate growth leaves (also animals) Determinate growth stops when organ(ism) reaches specific size 108 How long does growth continue? Annual; from germination to seed production within one year (includes major crops) Biennials; from germination to seed production in 2 years Perennials; long lived species. 109 Bristlecone pines – 5000 years 110 Yew (Taxus baccata) ~ 2000 years 111 Secondary growth Thickening of roots and shoots in woody plants Development secondary meristems ? Vascular cambium Cork cambium 112  Secondary growth A new meristem; vascular cambium 113 Secondary growth  Vascular cambium develops between xylem and phloem  Vascular cambium is cylinder of meristematic cells 114 Secondary growth  Vascular cambium located between xylem and phloem  Vascular cambium is cylinder of meristematic cells  Vascular cambium produces new xylem and phloem 115  Secondary growth xylem  Vascular cambium active summer – dormant winter  Spring formation large diameter xylem  Summer and autumn small diameter xylem  Year rings  Unique pattern depending on weather conditions 116  117 Climatological data are reflected in structure year rings Tree ring analysis Morphological data can be matched with radio-isotope data (carbon 12 and 13), resulting in comprehensive climate info 118 Little ice age 1570-1680 Slow growth trees  thin rings = Compact wood Late 1600’s & early 1700’s Stradivarius produced some of best ever violins & other string instruments from wood formed in little ice age Message: integration climate, plants, culture 119  Secondary growth  Old xylem non-functional  heartwood  stuffed with preservatives  absent  Young xylem  sapwood  Old phloem disintegrates 120 Secondary growth What happens when a trunk expands from the inside? The outside ruptures, as shown by this young oak tree 121 Secondary growth Oak Scots pine 122  Secondary growth A second meristem; Cork cambium 123  Secondary growth – cork cambium  Due to secondary growth – epidermis ruptures  Cork cambium produces cork cells  Cork cells covered by waxy suberin 124 Secondary growth – cork cambium 125 Secondary growth – cork cambium Periderm = cork cambium & cork Bark = phloem & periderm Bark = all tissues external from vascular cambium 126 Secondary growth 127 Cork versus bark Consequences …….? 128  Cork versus bark Tree will survive removal cork Removal bark means certain death (lack of phloem transport) 129  Cork versus bark Girdling or bark ringing to kill woody plants 130  Lectures on plant structure Campbell & Reece (ed. 8) Chapter 35, overview plus concepts 35.1 - 35.4 Campbell & Reece (ed. 9) Chapter 35, overview plus concepts 35.1 - 35.4 Campbell & Reece (ed. 10) Chapter 35, intro plus concepts 35.1 - 35.4 131