I'm studying a foundational herbal course with Heartwood Education.
Here, i am documenting my study.
Basic Plant Anatomy
A Simple Plant Cell
Learning plant families
Apiaceae (carrot family)
(Umbellifereae) Umbrella shaped flowers (umbels) flat heads make it easy for insects to land, rigid stems, divided leaves, alternate leaves, riged oval seeds, aromatic seeds, often have hollow stems
examples: Lovage, parsley, caraway, wild carrot,
Rosaceae (rose family)
Tend to have 5 petals and many stamens clustered in the centre of the flower, has divided leaves and lots of leaflets
examples: cherries, apples, mountain ash, bramble, agrimony
Lamiaceae (mint family)
Generally Square stems, opposite leaves usually simple, strong or pleasant smell from glandular leaf secretions, trumpet shape flowers that rung around the stem
examples: lavender, thyme, mint, rosemary, sage
Asteraceae (daisy family)
Flowers made up of many little tiny flowers within a ray florette structure, each small flower forms a seed,
examples: calendula, sunflower, artichoke, elecampane, dandelion, chicory
ACTIVITY: Botanical definitions
Find a definition of the following botanical terms and post them in this task forum:
Medicinal plants have chemical constituents that have medicinal actions.
I will be exploring 4 constituents: mucilages, tannins, saponins and essential oils.
Theses constituents are among many compounds that are synthesised as secondary to the primary needs of the plant (like the sugars made in the photosynthesis process).
Mucilages moisten and sooth, they support the digestion of minerals in the digestive system and help with something like a cough where we want to moisten and soothe.
Linseed/flax (Linum usitatissimum), is a great example of a mucilage producing plant, If you soak them in water for 10+ minutes (maceration) you can see that the liquid turns gloopy. Psyllium has a similar action (Plantago psyllium) and marshmallow root too (Althea officinalis).
Tannins were used for working animal hide into leather, this would prevent the skins from going off as they work to combine proteins, this can also help to seal wounds, They are astringent meaning they dry and constrict things, inclusing bodily tissues, and can be toning. In excess they can prevent the body from absorbing nutrients. You can see tannins forming on the sides of a mug when you brew a cup of black tea. Examples of plants that contain tannins are: black tea (Camelllia sinensis), Oak bark (Quercus robur), Vervain (Verbena officinalis), Eyebright (Euphrasia officinalis).
ACTIVITY: TANNINS TASK
Black tea steeped for 5 and 20 mins how does it taste and feel in your mouth? Use as many words as you can to describe this experience:
Saponins are glycosides (a kind of sugar) that make froth in water, they have a detergent effect. They are soft and demulscent (soothing, viscose and slimey), they strengthen blood vessel walls and can be divided into two main groups: Steroidal saponins and Triterpenoid saponins.
Examples of plants that contain saponins are: soapwort (Saponaria officinalis), and horse chestnut (Aesculus hippocastanum). Saponins are found in many foods for example: spinach, oats and tomatoes.
Essential oils are volatile oils, which mean they can easily vaporise into the air (where we can smell them). Peppermint (Mentha x piperita) is a great example. When we make infusions we want use a lid on the teapot or mug as the tea is brewing to stop these oils from evaporating,
Vascular tissue in more depth
Xylem + Phloem: are vascular tissues, they are a bit like pipes that move and distribute water, minerals and sugars etc around the plant. Plants create sugars via photosynthesis in the leaves, and receive water and minerals through the roots so they need a system to move these to other parts of the plant where they are needed. Xylem is the tissue that transports water, it flows in one direction - upwards. Phloem transports sugars around the plant, and can transport them in either direction. Xylem and Phloem tubes sit right next to each other. All of the veins in leaves, stems, roots, tree trunks etc are filled with these vascular tissues.
Xylem: transports water upwards, xylem cells are dead, rigid and strong. They are what forms wood or the tougher matter that forms plant stems. Water flows up the plant to the leaves, where it evaporates through tiny pores in the leaf called stomata. As a water molecule evaporates through the stomata, it effectively pulls other water molecules towards it, creating a strong upward pulling motion, this is what enables the water to move up the plant instead of falling down with the force of gravity. This process is called transpiration. At night when evaporation isn't possible, a process happens in the root: the plant actively uses energy to pull minerals into the roots, which in turn pulls water into the root through osmosis, again creating an upward flow of water.
Phloem: cells are living cells. Sugars are created in the leaves then are moved up and down the plant in a sugary sap to where they are needed. If one cell has too many sugar molecules and another doesn't have enough, the cell will use energy to 'load' the sugar molecules into the phloem, the phloem cell which will then be dense with sugar molecules will attract water from the xylem cells through osmosis, this region of the phloem starts to fill up with water increasing the pressure and the molecules will then flow through the phloem to the area that have less sugar pressure and less sugar molecule. They will then be 'unloaded' into the cells that needs them. The water will then move back into the xylem where the pressure is lower. This process is called translocation. Phloem cells have a companion cell, which holds necessary organelles like the nucleus that the phloem cells cannot hold due to their transportation purpose.
Herbal study 2: Plant Science (part 2)