93 Plants Trivia Questions and Answers
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Easy Plants Trivia Questions
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Which part of an aloe plant contains its familiar gel?
Leaves
Aloe stores its clear gel inside its thick, fleshy leaves.
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Bamboo belongs to which broad plant group?
Grass
Although some bamboos become tall and woody, bamboo is classified in the grass family.
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Botanically, the banana fruit belongs to which class of fruit?
A berry
Botanically, a banana is a berry that develops from one ovary.
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Botanically, what kind of plant is a banana?
A herb
A banana plant is a giant herb with a leaf-based pseudostem.
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Which part of a baobab can store large amounts of water?
Trunk
Baobab trunks are adapted to store water in dry climates.
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Which science is the study of plants?
Botany
Botany covers the structure, growth, reproduction and classification of plants, from mosses to forest trees. Zoology is the equivalent science for animals, geology deals with rocks and the Earth, and ecology studies how living things interact with each other and their surroundings.
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What type of root is the main edible part of a carrot?
Taproot
A carrot is a swollen taproot that stores food for the plant.
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Which coffee-fruit structure is the coffee bean?
The seed
The fruit is called a coffee cherry, and most cherries contain two flat seeds pressed face to face. When only one rounded seed forms, it is called a peaberry, and some producers sort and sell these separately.
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Which tree's bark can be stripped every nine years and simply grows back?
Cork oak
Cork stoppers are made from the thick, spongy bark of the cork oak (Quercus suber). The bark can be harvested repeatedly without killing the tree.
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Which plant produces soft fibers used to make much clothing?
Cotton
Cotton plants produce soft fibers around their seeds that are spun into textiles.
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Ferns reproduce and disperse using what instead of seeds?
Spores
Ferns produce spores rather than seeds.
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Linen is made from fibers of which crop?
Flax
Linen is spun from fibers obtained from flax stems.
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Which flower part produces pollen?
Anther
The anther is the pollen-producing part of a flower's stamen.
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What sugary liquid do many flowers produce to attract pollinators?
Nectar
Nectar is a sugar-rich liquid secreted by glands called nectaries, usually set deep inside the flower so a feeding bee, bird or bat has to push past the pollen to reach it.
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In flowering plants, a fruit usually develops from what structure?
Mature ovary
A fruit usually develops from the mature ovary after fertilization, with the ovary wall often becoming the fruit’s protective outer layer. In some fruits, such as apples, additional flower parts also contribute to the fleshy portion.
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Which stimulus guides most roots to grow downward?
Gravity
Gravity guides most roots to grow downward, a response called positive gravitropism. Specialized cells in the root cap help sense the direction of gravity.
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Which nutrient can legumes gain with help from bacteria in root nodules?
Nitrogen
Legumes can gain nitrogen through bacteria living in their root nodules, which convert atmospheric nitrogen into forms the plant can use. In return, the plant supplies the bacteria with energy-rich sugars.
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What is the edible seed of a corn plant commonly called?
Kernel
A corn kernel is the seed of a maize plant, attached to the cob. The husk is the leafy wrapper, and the silk is the bundle of styles, one thread for every kernel it pollinates.
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What liquid is boiled down to make Canada's traditional pancake syrup?
Maple sap
Maple syrup is made by boiling down the watery sap tapped from sugar maples in late winter, when freezing nights and mild days drive it up the trunk. The sap is only about two percent sugar, so around forty litres of it are boiled away to make a single litre of syrup.
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Mosses are commonly classified as what kind of plants?
Nonvascular plants
Mosses lack the specialized vascular tissues found in higher plants.
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Which kind of tree produces acorns?
Oak
Acorns are the fruits of oak trees.
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Lavender and rhubarb die back in winter but regrow from the same roots year after year. What kind of plants are they?
Perennial
The roots stay alive underground through winter dormancy, storing energy that fuels new growth each spring, unlike annuals, which die completely after setting seed in a single season.
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Which organelles carry out photosynthesis in plant cells?
Chloroplasts
Photosynthesis occurs in chloroplasts, which contain chlorophyll.
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What structure holds the seeds of a pine tree?
A cone
Pines are conifers, meaning cone-bearers. Their seeds sit exposed on the scales of a woody female cone rather than inside a fruit, and the scales flex open in dry weather to let the winged seeds spin away on the wind.
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What pigment gives most leaves their green color?
Chlorophyll
Chlorophyll is the pigment that gives most leaves their green color by absorbing mainly red and blue light while reflecting green light. It also captures light energy for photosynthesis.
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Which structure carries the male reproductive cells of seed plants?
Pollen
Pollen carries male gametophytes in seed plants.
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Which plant structures greatly increase surface area for water uptake?
Root hairs
Root hairs are tiny extensions of root cells that greatly increase surface area, helping the plant absorb water and dissolved minerals from the soil.
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What must a dormant seed take in before germination can begin?
Water
A dormant seed is extremely dry. Taking up water swells it, splits the seed coat and restarts the metabolism that drives germination. Botanists call that first soaking-up stage imbibition.
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What is the tiny plant within a seed called?
Embryo
The embryo is the tiny developing plant inside a seed, containing the beginnings of its root, shoot, and leaves. It remains dormant until the seed gets suitable conditions to germinate.
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What is the start of growth from a seed called?
Germination
Germination is the process in which a seed begins to grow into a seedling.
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What stems do strawberry plants use to make new plantlets?
Runners
Strawberry runners are horizontal stems that form new plantlets.
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What does an arborist look after?
Trees
An arborist plants, prunes, inspects and fells trees, and is often called a tree surgeon. The name comes from the Latin arbor, meaning tree.
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Which tissue carries water upward from plant roots?
Xylem
Xylem conducts water and dissolved minerals from roots through the plant.
Medium Plants Trivia Questions
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Flowering plants, or angiosperms, enclose their seeds inside which structure?
Fruits
An angiosperm seed develops inside a fruit, which grows from the flower's ovary after fertilisation. The fruit shields the seed and helps move it away from the parent plant by wind, water or animal. Conifers and other gymnosperms leave their seeds naked on a cone scale instead.
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Which field is the care and cultivation of individual trees and shrubs?
Arboriculture
Arboriculture is the practice behind the arborist or tree surgeon: planting, pruning, diagnosing disease and making trees safe, usually one tree at a time. Silviculture manages whole forests as a crop, horticulture covers garden and greenhouse plants, and agronomy covers field crops and soils.
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Which plant hormone helps a shoot grow toward light?
Auxin
Uneven auxin distribution promotes differential shoot growth in phototropism.
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Which tree species includes Methuselah, the oldest known individual tree at over 4,800 years?
Bristlecone pine
They grow high in California's White Mountains, where cold, dry conditions slow growth to a crawl and produce dense wood that resists rot, fungi and insects for thousands of years.
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Cactus spines are modified versions of which plant organ?
Leaves
A cactus spine is a leaf that evolved into a hard, narrow point. Losing the broad leaf blade leaves the plant with almost no surface from which water can evaporate.
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In many cacti, which organ carries out most photosynthesis?
Stem
The thick green stem does nearly all of a cactus's photosynthesis, and it stores the plant's water at the same time. That is why a cactus stays green with no foliage on it.
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Which spice is made from the dried inner bark of a tree?
Cinnamon
Cinnamon is the inner bark of Cinnamomum trees, peeled away and left to curl into quills as it dries. Nutmeg is a seed, cloves are flower buds and allspice is a dried berry.
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Cotton fiber develops from what part of the plant?
Seed hairs
Cotton fibers are hairs that grow from the surface cells of developing seeds and are spun into textile fiber.
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Which surface property of lotus leaves has inspired self-cleaning materials?
Water-repellent
A lotus leaf is covered in microscopic bumps coated in wax, so a water droplet rests on the tips of those bumps and touches almost none of the surface. The drop pulls itself into a near-sphere and rolls off at the slightest tilt, sweeping up dust as it goes. Copying that texture is how self-cleaning paints, glass and fabrics work.
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Which maize structure produces pollen?
Tassel
The tassel at the top of a maize plant bears the male flowers and pollen.
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Which plant is the main food source of monarch caterpillars?
Milkweed
Monarch caterpillars feed almost exclusively on milkweed plants, where monarchs also lay their eggs. Adult monarchs drink nectar from many flowers, including goldenrod and thistle, but their caterpillars cannot use them.
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What makes a sensitive plant's leaves fold shut within seconds of being touched?
Water pressure collapsing in cells at the base of each leaflet
At the base of every leaflet sits a swollen hinge of cells called a pulvinus. Touch makes those cells dump potassium ions, water follows the ions out, the hinge goes limp and the leaf drops shut, then slowly reinflates over several minutes.
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How many embryonic seed leaves does a grass embryo have?
One cotyledon
A grass is a monocot, whose embryo develops one cotyledon.
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A mycorrhiza is a partnership between plant roots and what?
Fungi
A mycorrhiza is a mutual arrangement between a plant's roots and a fungus. The fungal threads reach far out into the soil for water and phosphorus the roots could never touch, and the plant pays in sugars made by photosynthesis. Something like four out of five land plants have them.
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Which plant's latex contains morphine?
Opium poppy
The milky latex that seeps from a scored opium poppy seed capsule contains several alkaloids, including morphine and codeine.
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What fruit type is a peach?
Drupe
A peach is a drupe, a fleshy fruit that develops around a single hard stone containing its seed. Other familiar drupes include cherries, plums, and mangoes.
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Which tissue transports sugars around a plant?
Phloem
Phloem transports sugars and other organic nutrients from sources to sinks.
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What does the liquid pooled at the bottom of a pitcher plant contain?
Digestive enzymes
Pitcher plants typically grow in nitrogen-poor bogs, so trapped insects supply nutrients the soil cannot provide. Downward-pointing hairs and slick, waxy walls stop prey from climbing back out once it slips into the fluid below.
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In pitcher plants, the trap is a modified version of which plant part?
A leaf
Each trap is a single leaf rolled into a tube and part-filled with fluid. Nectar on a slippery rim draws insects in, downward-pointing hairs stop them climbing back out, and the plant digests them for the nitrogen its boggy soil cannot supply. Its flowers grow separately, on tall stalks held well clear of the traps.
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Which polysaccharide forms the main structural framework of plant cell walls?
Cellulose
Cellulose is a long chain of glucose units, and the chains line up into cable-like bundles that give the cell wall its tensile strength - the reason a stem can hold a plant upright. Pectin and hemicellulose form the softer matrix around those cables, while chitin does the equivalent structural job in fungi and insect shells.
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What oily substance in poison ivy causes its familiar rash?
Urushiol
Poison ivy contains urushiol, an oil that can trigger an itchy skin reaction.
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What kind of organ is a ginger rhizome?
An underground stem
Ginger's rhizome is a horizontal underground stem that stores food and forms shoots.
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Rice belongs to which plant family?
Grass family
Rice is a cereal grass in the family Poaceae.
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Plantations of the tree Hevea brasiliensis are tapped to produce what?
Natural rubber
Hevea brasiliensis, the Para rubber tree, is native to the Amazon and supplies almost all the world's natural rubber. Tappers cut a shallow spiral groove in the bark and the milky latex runs down into a cup; seeds taken out of Brazil in 1876 founded the huge plantations of Southeast Asia.
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What structure carries male genetic material to an ovule in a flowering plant?
Pollen tube
After a pollen grain lands on the stigma, it grows a pollen tube down through the style and delivers two sperm cells into the ovule, where fertilisation takes place.
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What tiny leaf openings regulate gas exchange?
Stomata
Stomata are pores, usually in leaves, that regulate gas exchange and water loss.
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What is a sunflower's large head botanically made of?
Many small flowers
A sunflower head is an inflorescence containing many individual flowers.
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Botanically, what type of fruit is a tomato?
A berry
A tomato develops from an ovary and has seeds within a fleshy pericarp, which makes it a berry botanically.
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The Venus flytrap is native to which US region?
The Carolinas
The Venus flytrap is native to the coastal regions of North and South Carolina. It grows naturally in wet, acidic soils such as bogs and savannas.
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What do Venus flytraps use to detect prey inside their traps?
Trigger hairs
The trap's tiny trigger hairs must be touched twice within about twenty seconds before it snaps shut. That double check keeps the plant from wasting a closure on a raindrop or a falling leaf.
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Aspirin was developed from a painkilling compound found in the bark of which tree?
Willow
Willow bark was a folk remedy for pain and fever for centuries. The compound salicin was isolated from it in the 1820s, leading to salicylic acid and then to aspirin.
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Hyperion, a coast redwood in California, is the tallest living tree ever measured. About how tall is it?
About 116 m (380 ft)
Hyperion was found in Redwood National Park in 2006 by naturalists Chris Atkins and Michael Taylor. Its exact location stayed secret for years, but off-trail visitors trampling the surrounding ferns led officials to close the area to the public in 2022.
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Pando, a single quaking aspen clone in Utah, is considered the most massive known living organism on Earth. About how much does it weigh?
About 6,000 tonnes
Pando looks like a forest of about 47,000 separate trees, but every trunk shares one root system and identical DNA, making the whole grove a single organism covering 43 hectares (106 acres) in Fishlake National Forest. Despite its size, Pando is in decline, as grazing deer and cattle eat new shoots before they can mature into trunks.
Hard Plants Trivia Questions
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Yucca flowers depend on one specialized pollinator, which also lays its eggs inside them. What kind of animal is it?
A moth
A female yucca moth deliberately gathers pollen, packs it onto a yucca flower's stigma, then lays eggs in the same flower. Her larvae eat some of the resulting seeds and leave the rest to mature.
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Sisal rope is made from fiber taken from which plant?
Agave
Sisal is stripped from the long, stiff leaves of Agave sisalana. Flax, hemp and jute all give up their fiber from the stem instead.
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What is a plant called when it grows on another plant for support without feeding from it?
An epiphyte
An epiphyte grows on another plant purely for a perch, taking its water and nutrients from rain and air. Many orchids, bromeliads and ferns live this way.
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Natural vanilla comes from the cured seed pods of which kind of plant?
An orchid
Vanilla is the cured fruit of climbing orchids in the genus Vanilla, chiefly Vanilla planifolia, which is the only orchid grown as a major food crop.
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What botanical fruit type is an apple?
Pome
An apple is a pome, a fruit with much flesh derived from floral tissues around the ovary.
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Which plant family includes daisies, sunflowers, and chrysanthemums?
Aster family
Daisies, sunflowers and chrysanthemums belong to Asteraceae, also called the aster or daisy family, one of the largest families of flowering plants.
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Which pigments can produce red autumn leaf colors?
Anthocyanins
Anthocyanin pigments contribute red and purple colors in many autumn leaves.
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Which tree genus was the original source of quinine?
Cinchona
Quinine was obtained from the bark of Cinchona trees, which are native to the Andes, and was the first effective treatment for malaria.
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The fluffy parachute that lets a dandelion seed ride the wind is known by what botanical name?
Pappus
Each dandelion seed hangs beneath a pappus, a crown of fine hairs that behaves like a parachute and can hold the seed aloft for a kilometre or more.
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What is the study of tree rings called?
Dendrochronology
Dendrochronology uses tree ring patterns to date wood and reconstruct past climate. Dendrology is the study of trees generally, phenology the timing of seasonal events and palynology the study of pollen.
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A fig is a hollow ball of flowers, pollinated by an insect that crawls in through a tiny hole at its tip. Which insect?
A wasp
The opening is so narrow that the female often loses her wings and antennae squeezing through; once inside she pollinates the flowers and lays her eggs, and each fig species typically depends on just one matched wasp species.
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What natural event can open serotinous pine cones?
Fire
Heat from wildfire can open serotinous cones and release their seeds.
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The heart drug digoxin is extracted from the leaves of which garden flower?
Foxglove
Digoxin comes from foxgloves, chiefly the woolly foxglove Digitalis lanata. William Withering described the use of foxglove leaves for heart conditions in 1785.
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Dodder is a leafless orange vine with almost no chlorophyll. How does it feed?
It taps into the stems of other plants
Dodder twines around a host and pushes root-like structures called haustoria into its stems to draw off water and sugars. Once attached, its own link to the soil withers away.
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What bacteria inhabit legume root nodules and fix nitrogen?
Rhizobia
Rhizobia live in legume root nodules, where they convert atmospheric nitrogen into forms the plant can use. In return, the plant supplies the bacteria with energy-rich compounds made through photosynthesis.
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Which arching aerial roots drop from the trunk and branches of a red mangrove to brace it in soft mud?
Prop roots
Red mangroves stand on prop roots, also called stilt roots: arching roots that grow down from the trunk and lower branches into the mud, spreading the tree's weight across soft sediment and taking in air through pores called lenticels above the waterline.
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Which plant family includes tomatoes, potatoes, and tobacco?
Nightshade family
Tomatoes, potatoes, peppers, aubergines and tobacco all belong to Solanaceae, commonly called the nightshade family.
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The three numbers on a bag of fertiliser are its NPK ratio. Which nutrients do those letters stand for?
Nitrogen, phosphorus and potassium
They are the three nutrients plants need in the largest amounts, and K is potassium from its Latin name kalium.
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An onion bulb is mainly made of swollen bases of what?
Leaves
The fleshy scales of an onion bulb are swollen leaf bases.
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Orchids do not shed loose pollen grains; they hand over their pollen in compact sticky masses. What are those masses called?
Pollinia
An orchid packages almost all of its pollen into one or two waxy lumps called pollinia. They are glued to a visiting insect, usually on the head or back, and carried whole to the next flower, so a single visit can pollinate an entire bloom. It is an all-or-nothing strategy, which is why many orchids go to such lengths to lure one specific pollinator.
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A pineapple's skin is a grid of hexagons, each one a separate flower. Which class of fruit does that make it?
A multiple fruit
A pineapple forms when the fruits of an entire inflorescence fuse together.
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Which plant produces the largest single flower by diameter?
Rafflesia arnoldii
It grows as a parasite inside vines in the rainforests of Sumatra and Borneo, with no leaves, stem or roots of its own, and its blooms reek of rotting meat to attract the carrion flies that pollinate it.
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Saffron consists of dried parts of which flower structure?
Stigmas
Saffron is made from the dried red stigmas of the saffron crocus, three to a flower, which is why it is picked by hand and priced accordingly.
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How is a strawberry classified botanically?
Accessory fruit
The red flesh of a strawberry is not fruit at all in the botanical sense, but the swollen receptacle at the top of the flower stalk. The true fruits are the tiny pips dotted across the surface, each one a separate dry achene with a seed inside. A fruit built mainly from tissue other than the ovary is called an accessory fruit.
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Shown a Madagascan orchid with a nectar spur about 30 centimetres long, Charles Darwin predicted what?
That a moth with a tongue that long must exist
In 1862 Darwin argued that Angraecum sesquipedale had to be pollinated by an insect able to reach the nectar at the bottom of its spur. A matching hawkmoth was described in 1903 and finally filmed feeding at the flower in the 1990s.
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A tree grows thicker by adding new wood from a thin living layer just under the bark. What is that layer called?
The cambium
The cambium is a sleeve of dividing cells between the wood and the inner bark, laying down new wood on its inner face and new inner bark on its outer face. Stripping a ring of bark kills a tree because it severs this layer.
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Which plant sends up a flowering spike nearly three metres tall, made of thousands of tiny flowers, that reeks of rotting meat?
Titan arum
The titan arum of Sumatra produces the largest unbranched inflorescence of any plant, a spike up to about three metres tall carrying thousands of tiny flowers inside a frilled sheath. Its stench of rotting flesh draws carrion beetles and flesh flies, and a single plant may go years between blooms.
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