🎯 What You'll Learn🎯 Objektif Pembelajaran
Describe plant tissue types - meristematic and permanent tissuesMenerangkan jenis tisu tumbuhan — tisu meristem dan tisu kekal (permanen)
Compare primary and secondary growth in plantsMembandingkan pertumbuhan primer dan sekunder pada tumbuhan
Explain the role of apical and lateral meristemsMenerangkan peranan meristem apikal dan meristem lateral
Sketch and interpret growth curves (sigmoid curve)Melakar dan mentafsir lengkung pertumbuhan (lengkung sigmoid)
Identify internal and external factors affecting plant growthMengenal pasti faktor dalaman dan luaran yang mempengaruhi pertumbuhan tumbuhan
🔥 Plant Tissues | Tisu Tumbuhan🔥 Tisu Tumbuhan
Meristematic Tissue (Tisu Meristem)Tisu Meristem
Actively dividing cells found at growth points in the plant.Sel yang aktif membahagi di kawasan pertumbuhan tumbuhan.
| TypeJenis | LocationLokasi | FunctionFungsi |
|---|---|---|
| Apical MeristemMeristem Apikal | Tips of roots and shootsHujung akar dan pucuk | Primary growthPertumbuhan primer – increases length/heightmenambah tinggi tumbuhan |
| Lateral MeristemMeristem Lateral | Sides of roots and stemsSisi akar dan batang | Secondary growthPertumbuhan sekunder – increases diameter/girthmenambah diameter batang |
| Vascular CambiumKambium Vaskular | Between xylem and phloemAntara xilem dan floem | Produces secondary xylem and phloemMenghasilkan xilem sekunder dan floem sekunder |
| Cork CambiumKambium Gabus | Outer cortex regionKawasan korteks luar | Produces cork (bark) for protectionMenghasilkan gabus (kulit kayu) untuk perlindungan |
Permanent Tissue (Tisu Permanen)Tisu Kekal (Tisu Permanen)
Non-dividing cells that have differentiated to perform specific functions.Sel yang tidak membahagi dan telah terbeza untuk menjalankan fungsi khusus.
| TypeJenis | SubtypesSubjenis | FunctionFungsi |
|---|---|---|
| Ground TissueTisu Asas | Parenchyma, Collenchyma, SclerenchymaParenkima, Kolenkima, Sklerenkima | Storage, support, photosynthesisSimpanan, sokongan, fotosintesis |
| Dermal TissueTisu Derma | Epidermis, PeridermEpidermis, Periderm | Protection of the plant bodyMelindungi badan tumbuhan |
| Vascular TissueTisu Vaskular | Xylem, PhloemXilem, Floem | Transport of water and nutrientsMengangkut air dan nutrien |
• "Xylem = X = Up" – Water goes UP from rootsAir naik dari akar ke daun
• "Phloem = Flow = Down" – Photosynthates flow DOWNHasil fotosintesis mengalir turun
• "Primary = Apical = Height" – Apical meristem grows tallerMeristem apikal menambah tinggi
• "Secondary = Lateral = Width" – Lateral meristem grows widerMeristem lateral menambah lebar
🌱 Primary vs Secondary Growth🌱 Pertumbuhan Primer vs Pertumbuhan Sekunder
| FeatureCiri | Primary GrowthPertumbuhan Primer | Secondary GrowthPertumbuhan Sekunder |
|---|---|---|
| MeristemMeristem | ApicalApikal | Lateral (vascular cambium, cork cambium)Lateral (kambium vaskular, kambium gabus) |
| ResultHasil | Increase in length/heightPenambahan tinggi | Increase in diameter/girthPenambahan diameter |
| Occurs inBerlaku pada | All plantsSemua tumbuhan | Woody plants onlyTumbuhan berkayu sahaja |
| SpeedKelajuan | FasterLebih cepat | SlowerLebih perlahan |
| StructuresStruktur | Primary xylem, primary phloemXilem primer, floem primer | Secondary xylem (wood), secondary phloem (bark)Xilem sekunder (kayu), floem sekunder (kulit kayu) |
📈 Growth Curves | Lengkung Pertumbuhan📈 Lengkung Pertumbuhan
Organisms typically follow an S-shaped (sigmoid) growth curve.Organisma biasanya mengikuti lengkung pertumbuhan berbentuk S (sigmoid).
| PhaseFasa | DescriptionKeterangan |
|---|---|
| Lag PhaseFasa Lag | Slow growth; cells are adapting and preparing for divisionPertumbuhan perlahan; sel menyesuaikan diri dan bersedia untuk pembahagian |
| Log (Exponential) PhaseFasa Log (Eksponen) | Rapid growth; cells dividing quickly, rate of growth increasesPertumbuhan pesat; sel membahagi dengan cepat, kadar pertumbuhan meningkat |
| Stationary PhaseFasa Matang | Growth slows; resources becoming limitingPertumbuhan perlahan; sumber menjadi terhad |
| Death / Senescence PhaseFasa Kematian | Organism dies; no further growth occursOrganisma mati; tiada pertumbuhan berlaku |
⚡ Factors Affecting Plant Growth⚡ Faktor Mempengaruhi Pertumbuhan Tumbuhan
| Internal FactorsFaktor Dalaman | External FactorsFaktor Luaran |
|---|---|
| GeneticsGenetik | Light intensityKeamatan cahaya |
| Hormones – auxin, gibberellin, cytokininHormon — auksin, giberelin, sitokinin | TemperatureSuhu |
| Water availabilityKetersediaan air | |
| Nutrients in soilNutrien dalam tanah | |
| Carbon dioxide concentrationKepekatan karbon dioksida |
💯 Quick Check💯 Semakan Cepat
Why is dry mass the most accurate method to measure plant growth?Mengapakah jisim kering kaedah paling tepat untuk mengukur pertumbuhan tumbuhan?
🇲🇾 Malaysian InnovationInovasi Malaysia
🌴 Oil palmKelapa sawit – Secondary growth produces the thick, strong trunk needed to support heavy fruit bunches.Pertumbuhan sekunder menghasilkan batang tebal dan kuat untuk menyokong tandan buah yang berat.
🌸 Rubber tree (Hevea brasiliensis)Pokok getah (Hevea brasiliensis) – Tapping harvests latex from the phloem, a product of secondary growth.Menyadap getah dari floem, hasil pertumbuhan sekunder.
🌾 BambooBuluh – A grass that shows rapid primary growth but NO secondary growth, proving that not all plants grow wider.Rumput yang menunjukkan pertumbuhan primer pesat tetapi TIADA pertumbuhan sekunder, membuktikan bukan semua tumbuhan bertambah lebar.
SPM 2020 Paper 2SPM 2020 Kertas 2
The diagram below shows a cross-section of a dicotyledonous stem undergoing secondary growth.Rajah di bawah menunjukkan rentas batang dikotiledon yang mengalami pertumbuhan sekunder.
(a) State TWO structures formed by the vascular cambium. [2 marks]Nyatakan DUA struktur yang dibentuk oleh kambium vaskular. [2 markah]
(b) Explain why monocotyledonous plants do not undergo secondary growth. [2 marks]Terangkan mengapa tumbuhan monokotiledon tidak mengalami pertumbuhan sekunder. [2 markah]
(c) Give ONE reason why measuring dry mass is more accurate than measuring length for plant growth. [1 mark]Berikan SATU sebab mengapa pengukuran jisim kering lebih tepat berbanding pengukuran panjang untuk pertumbuhan tumbuhan. [1 markah]