Minor in Biology

Light microscope photo of the cyanobacterium Anabaena azollae, with heterocytes

Scanning electron microscope photo of a pollen grain of Clivia

Tip of a stem of Cycas circinalis, with megasporophylls

One of the most common native lichens, Xanthoria parietina, with apothecia

Foliose liverwort Lophocolea heterophylla with sporogones

Branch of the common yew (Taxus baccata) with microsporangiate (= male) cones

Red alga, Delesseria sanguinea, Rhodophyta

Antheridial heads of Polytrichum

Branches of Ephedra distachya with seed between fleshy scales

Ovary of Narcissus pseudonarcissus, longitudinal section, showing numerous ovules

Branches with cones of European larch (Larix decidua); pollen cones yellow, ovulate cone red, mature seed cone brown

Peat moss (Sphagnum spec.) with sporogones

Fruiting body of the fly agaric (Amanita muscaria, Basidiomycetes)

Fruiting bodies (apothecia) of the Black Bulgar (Bulgaria inquinans, Ascomycetes)

Moss with sporogones

Embryo of a pea (Pisum sativum), one cotyledon separated, plumule (shoot bud) and radicle (initiation of primary root) clearly visible

Flower of Amborella trichopoda, sister group of all other angiosperms (often addressed as 'the most primitive living angiosperm')

Bladderwrack, Fucus vesiculosus (brown algae, Phaeophyceae)

Ovulate cone of a cypress (Cupressus), with pollination droplets on tubular micropyles

Green alga Ulva intestinalis

Immature cone of Larix decidua: longitudinal section (left); seed scale with two developing seeds (right)

Light microscope photo of a moss rhizoid

Scanning electron microscope photo of the peristome of Funaria hygrometrica

Light microscope photo of a section of a seed of Petunia axillaris; pericarp visible in the upper right hand corner, placenta in the lower right hand corner

Scanning electron microscope photo of Streptocarpus pollen grains

Root systems: allorhizal = with a primary root and secondary roots (left) and homorhizal = with more or less equal roots (right)

Storage roots (Campanula rapunculoides, left) and root tubers (Ficaria verna, right)

Dichasial vegetative branching in (Syringa vulgaris)

Spine (pointed woody brachyblast) of Prunus spinosa bearing flower buds

Phylloclades (leaf-like stems) of Ruscus aculeatus, in the right photo with a flower

Scandent plants: twining in Humulus lupulus (left); by shoot tendrils in Vitis vinifera (right)

Rhizome = a subterranean stem serving as storage organ, in Anemone nemorosa

Stolons = elongated stems as a means of vegetative reproduction in Potentilla anserina

Stolons forming tubers in Solanum tuberosum

The three basic types of leaf arrangement: 1 leaf per node = alternate (Veronica filiformis, left); 2 leaves per node = opposite (Stellaria graminea, center); > 2 leaves per node = verticillate (Hippuris vulgaris, right)

Photos of special cases of alternate leaf arrangement: distichous in Phalaris arundinacea (left); tristichous in Ceratrum album (center); spiral (3/8) in Hypochaeris radicata (right)

Perfect spirals in Romanesco cabbage (Brassica oleracea var. botrytis), organs following each other with the limit divergence angle of ca. 137.5°

Structures of the leaf base: stipules in Malus spec. (left); leaf sheath in Angelica archangelica (right)

Basic types of leaf venation: parallel in Deschampsia caespitosa (left); pinnate in Carpinus betulus (right)

Leaf margins, from left to right: entire (Syringa vulgaris); serrate (Forsythia intermedia); aculeate-dentate (Mahonia aquifolium); crenate (Glechoma hederacea); sinuate (Quercus petraea)

Palmately dissected leaves in Malva moschata

Pinnate leaf of a vetch (Vicia spec.), with stipules and tendrils

Palmately compound leaves of Lupinus polyphyllus

Simple racemose inflorescences, from left to right: raceme = axis elongate, flowers pedicellate (Brassica napus); spike = axis elongate, flowers sessile (Orobanche hederae); umbel = axis extremly short, flowers pedicellate (Astrantia major); capitulum = head = axis extremely short, flowers sessile (Scabiosa lucida)

Cymose inflorescences: dichasium (Stellaria holostea, left); scorpioid cyme (Symphytum officinale, right)

Compound inflorescences: panicle (Ligustrum vulgare, left); funnel-shaped corymb (Filipendula ulmaria, center); thyrse (Aesculus hippocastanum, right)

Inflorescences (catkins) of poplars (Populus spp.): pistillate (left) and staminate (right)

Flower of Gagea lutea, with a perigone = perianth parts more or less equal

Flower of Spergula arvensis, with perianth consisting of calyx and corolla

Apochlamydeous flowers (= without any perianth) of the common ash (Fraxinus excelsior)

Flower of Dianthus deltoides: actinomorphic = with more than 2 planes of symmetry

Flowers of the bleeding heart (Lamprocapnos spectabilis): disymmetric = with 2 planes of symmetry perpendicular to one another

Flowers of Euphrasia officinalis: zygomorphic = with a single plane of symmetry

Flowers of Corydalis cava, their spur chewed open by bumblebees

Flowers of Anemone nemorosa (Ranunculaceae), with a perigone = perianth parts more or less equal and a polymerous androecium = stamens numerous

Flowers with diplostemonous androeceum = twice as many stamens as petals (Oxalis corniculata, left) and with haplostemonous androeceum = as many stamens as petals (Sambucus nigra, right)

Different types of anther dehiscence: longicidal = lengthwise, the most common type (Lilium martagon, left), poricidal = with pores or very short slits (Solanum tuberosum, center), and valvate = with flaps (Mahonia aquifolium, right)

Fusion of filaments: with the corolla tube, leading to a joint stamen-corolla tube (Syringa vulgaris, left); with each other, leading to a filament tube separate from the corolla (Malva moschata, right)

Gynoecia: choricarpous = consisting of several free carpels (Helleborus niger, left); coenocarpous = consisting of several (here 3) fused carpels (Tropaeolum majus, right), note single style with 3 stigmatic branches

Ovary positions: superior = flower hypogynous = all other floral parts inserted below the insertion of the gynoecium (Hyacinthoides non-scripta, left); inferior = flower epigynous = all other flower parts inserted on top of the ovary (Galanthus nivalis, right)

Placentation types in choricarpous gynoecia: submarginal = along the ventral suture of the carpel (Aquilegia vulgaris, left) and laminal = scattered on the entire surface (Nymphaea), in cross section (center) and longitudinal section (right)

Placentation types in coenocarpous gynoecia: axile = in the center of a septate ovary (Tulipa gesneriana, left); parietal = on the ovary wall (Menyanthes trifoliata, right)

Free central placentation in Primula vulgaris: longitudinal section of flower (left); cross section of young fruit (right)

Open follicles in Eranthis hyemalis

Legumes of Vicia sativa: mature but still closed (left); dehisced (right)

Monocarpellate berries in Berberis thunbergii

Peach (Prunus persica), longitudinal section

Nutlets in Ranunculus sceleratus

Fleshy fruits with nutlets: strawberry (Fragaria x ananassa, left), with a buldging receptacle as the fleshy part; hip of Japanese rose (Rosa rugosa, right), with hypanthium as the fleshy part

Fruit consisting of drupelets in raspberry (Rubus idaeus); sepals, stamens and styles still preserved

Fruits (loculicidal capsules) of Iris pseudacorus

Septicidal capsule = opening in the plane of the septa in Digitalis purpurea

Capsules with special types of dehiscence: valvate by teeth in Silene dioica (left); poricidal = by pores in Papaver dubium (center); operculate = with a lid in Plantago lanceolata (right)

Fruits (siliques) of Erysimum cheiri

Longitudinal section of a tomato (Lycopersicon esculentum), a berry with fleshy pericarp and sarcotestal seeds

Cross section of an olive (Olea europaea), a bicarpellate drupe; testa, endosperm and embryo visible in the only developed seed, septum and an aborted ovule in the second locule visible; embedded in methacrylate resin

Immature fruits (acorns) of the common oak (Quercus robur); nuts in a cupule

Fruits (samaras) of Ulmus glabra

Fruit (schizocarp) of Anchusa arvensis

Schizocarps: Alcea rosea (left); Anthriscus sylvestris (center); Acer pseudoplatanus (right)

Inflorescences of Liliaceae: solitary flower in Fritillaria meleagris (left), raceme in Lilium martagon (center), pseudo-umbel in Fritillaria imperialis (right)

Flowers of Liliaceae: Tulipa sylvestris (left) and Lilium bulbiferum (right), showing the typical construction of the family: actinomorphic, with 3+3 (sub)equal tepals, 3+3 stamens and a superior ovary consisting of three fused carpels

Ovary of Tulipa gesneriana: lateral view (left); cross section (right)

Fruits (loculicidal capsules) of Liliaceae: Tulipa gesneriana (left), Lilium regale (right)

Flowers of Asparagaceae: Anthericum liliago (left), with free tepals; Polygonatum multiflorum (right), with fused tepals

Asparagaceae fruits: loculicidal capsules in Muscari botryoides (left), berries in Convallaria majalis (right)

Inflorescences in Amaryllidaceae: many-flowered (pseudo-)umbel in Allium flavum (left); two-flowered umbel in Leucojum vernum (center); single flower in Galanthus nivalis (right)

Inflorescences in Asparagaceae: solitary flower in Asparagus officinalis (left); raceme in Muscari latifolium (right)

Amaryllidaceae flowers: Narcissus poeticus (left), with a paracorolla; Allium ursinum (right), an exception within the family because of its superior ovary

Flower of Galanthus nivalis (Amaryllidaceae), longitudinal section, showing inferior ovary

Amaryllidaceae fruits: Narcissus pseudonarcissus (left), a loculicidal capsule; Galanthus nivalis (right), a transitional form between capsule and berry

Crops plants in Amaryllidaceae: Onion (Allium cepa, left), longitudinal section of the bulb; Chives (Allium schoenoprasum, center), flowering plant; Leek (Allium porrum, right)

Pulsatilla vulgaris (Ranunculaceae)

Leaves of Ranunculaceae: undivided in Caltha palustris (left); bipinnate in Actaea racemosa (right)

Deeply palmately dissected leaf of Ranunculus acris (Ranunculaceae)

Flower of Helleborus niger (Ranunculaceae), seen from back side, with simple perianth and bracts below the flower

Flowers of Helleborus niger (Ranunculaceae), with nectar leaves between perianth and androecium

Petals derived from nectar leaves in Ranunculus acris (Ranunculaceae): entire flower, lateral view (left); single petal = nectar leaf (right), note nectar gland at the base

Flower of Aquilegia vulgaris (Ranunculaceae), with five spurred nectar leaves

Zygomorphic flowers in Ranunculaceae: spurred in Consolida regalis (left); helmet-shaped in Aconitum lycoctonum (right)

Flowers of a garden form of Delphinium elatum (Ranunculaceae): tip of a partial inflorescence (left); longitudinal section of a flower (right), with a nectar leaves reaching deeply into the spur, one of them removed and placed above the flower

The most common fruit types in Ranunculaceae: nutlets in Ranunculus sceleratus (left); follicles in Eranthis hyemalis (right)

Fruit of Clematis vitalba (Ranunculaceae): nutlets with densely pubescent styles

Actaea spicata, with its solitary carpel and berries an exception among the Ranunculaceae: flowers (left) and fruits (right)

Leaf bases of Rosaceae, with stipules: Malus spec. (left); Sorbus aucuparia (right)

Rosaceae flowers with epicalyx, seen from back side: Potentilla neumanniana (left), Fragaria ananassa (right)

Rosaceae flowers: Rosa multiflora (left), with the typical flower construction; Sanguisorba minor (right), with unisexual flowers arranged in a head

Longitudinal sections of Rosaceae flowers: Rosa rugosa (left), carpels enclosed in hypanthium; Geum rivale (right), carpels raised on a gynophore

Photos of the gynoecium position in Rosaceae: superior = flower hypogynous in Fragaria moschata (left); in hypanthium = flower perigynous in Prunus serotina (center); inferior = flower epigynous in Malus domestica (right)

Follicles of Physocarpus opulifolius (Rosaceae)

Photos of special nutlets in Rosaceae: Geum urbanum (left), with styles acting as barbs; Filipendula ulmaria (right), with twisted nutlets

Fruits consisting of druplets in Rosaceae: Rubus saxatilis (left); R. caesius (right)

Rosaceae, fleshy fruits with nutlets: strawberry (Fragaria x ananassa, left), with enlarged fleshy receptacle; hip of Japanese Rose (Rosa rugosa, right), hypanthium fleshy

Longitudinal sections of fleshy fruits of Rosaceae: Apple (Malus domestica, left), an inferior berry; Apricot (Prunus armeniaca, right), a drupe

Species showing the typical rough indument of Boraginaceae: Achusa azurea (left); Symphytum officinale (right)

Tip of the scorpioid cyme of Myosotis arvensis (Boraginaceae)

Flowers of Pentaglottis sempervirens (Boraginaceae), with protruding faucal scales

Zygomorphic flowers, a rare character in Boraginaceae: Echium vulgare (left), Anchusa arvensis (right)

Photo of a longitudinally opened corolla of Symphytum officinale (Boraginaceae), with faucal scales alternating with stamens

Immature fruit (schizocarp) of Pentaglottis sempervirens (Boraginaceae)

Photos of the characteristic vegetative characters of Lamiaceae: quadrangular stems and opposite leaves, in Lamium purpureum (left) und Lycopus europaeus (right)

Typical zygomorphic Lamiaceae flowers in Galeopsis bifida

Longitudinal section of a flower of Lamium maculatum (Lamiaceae)

Flower of Teucrium chamaedrys (Lamiaceae)

Calyces of Leonurus cardiaca (Lamiaceae), with almost mature fruits

Halophytic Brassicaceae on the shore of the Baltic sea: Crambe maritima (left); Cakile maritima (right)

Leaves in Brassicaceae: Capsella bursa-pastoris (left), undivided, sessile, amplexicaul; Barbarea vulgaris (center), pinnatifid, sessile, auriculate; Lunaria annua (right), cordate, petiolate

The typical inflorescence in Brassicaceae: ebracteate racemes, in Arabidopsis thaliana (left) and Brassica napus (right)

The typical flower construction in Brassicaceae, K4 C4 A2+4 G(2): Rorippa sylvestris (left); Cardamine amara (right)

Fruits in Brassicaceae: beaked silique in Eruca sativa (left); silicle in Thlaspi arvense (right)

Roots of Trifolium dubium (Fabaceae), with nodules

Fabaceae leaves: Trifolium dubium (left), with stipules at the base of the petiole; Phaseolus vulgaris (right), with stipellules at the bases of the petiolules

Pinnate leaf of Vicia sativa (Fabaceae), with tendrils derived from leaflets

Inflorescences of Fabaceae: almost capitulate in Trifolium badium (left); raceme in Melilotus albus (right)

Flowers of Fabaceae: Ornithopus perpusillus (left), with red-veined banner, paler wings and yellow keel; Lupinus polyphyllus (right), wings and half of the keel removed, showing the filament tube

Legumes of Vicia sativa (Fabaceae): still closed (left); dehisced (right)

Leaves in Caryophyllaceae: Cerastium fontanum (left), opposite, sessile, without stipules and apparently 1-nerved, the most common pattern in Caryophyllaceae; Spergula arvensis (center), pseudo-verticillate; Spergularia rubra (right), with membraneous interpetiolar stipules

Dichasial inflorescence of Stellaria aquatica (Caryophyllaceae)

Caryophyllaceae flowers: Spergularia rubra (left), with free sepals; Silene vulgaris (right), with fused sepals

Flowers of Silene dioica (Caryophyllaceae), opened longitudinally: female (left) and male (right)

Photo of a capsule of Cerastium fontanum (Caryophyllaceae), opening by teeth

Alopecurus pratensis (Poaceae): upper end of leaf sheath, with ligule (left); longitudinal section of culm, with solid node (right)

Panicle branch of Poa pratensis (Poaceae), with flowering spikelets

Poaceae spikelets: Bromus secalinus (left), lemmae with awns; Briza media (right), without awns

Spikelet and flower parts of Festuca rubra (Poaceae): on the left three closed flowers, a lemma (with awn) and a palea (without awn) removed; in the center and on the right two flowers without their floral bracts

Fruiting spikelets of Arrhenatherum elatius (Poaceae), with bent awns

Stems and leaves of Juncaceae: Luzula campestris (left), with pubescent leaf sheath; Juncus effusus (center), longitudinal section of leaf; Juncus articulatus (right)

Inflorescence of Luzula campestris (Juncaceae)

Flowers of Juncus tenuis (Juncaceae)

Infructescence of Juncus inflexus (Juncaceae)

Details of Carex hirta (Cyperaceae): stem with leaf sheaths (left); pistillate flowering spike (center); staminate flowering spike (right)

Photos of Schoenoplectus lacustris (Cyperaceae): base of shoot (left); longitudinally cut shoot (center); tip of shoot with flowering spikelets (right)

Scirpus silvaticus (Cyperaceae): entire inflorescence (left) and detail (right)

Fruiting spikes of Carex (Cyperaceae): C. pseudocyperus (left); C. riparia (right)

Infructescences of Eriophorum (Cyperaceae): E. angustifolium (left); E. vaginatum (right)

Flowering Plantaginaceae: Misopates orontium (left); Digitalis grandiflora (center); Globularia cordifolia (right)

Flower of Cymbalaria muralis: frontal view (left) and longitudinal section (right)

Fruits of Plantaginaceae: septicidal capsules in Digitalis purpurea (left), poricidal capsules in Antirrhinum majus (center), operculate capsules in Plantago lanceolata (right)

Aquatic plants in the Plantaginaceae: Hippuris vulgaris (left), Callitriche spec. (right)

Leaves of Apiaceae: Helosciadium nodiflorum (left), simply pinnate; Chaerophyllum bulbosum (right), multiply pinnate

Upper stem leaf of Angelica sylvestris (Apiaceae), with big leaf sheath

The typical compound umbel of Apiaceae (Laserpitium siler)

Details of Apiaceae inflorescences: first-order branching of the umbel in Conium maculatum (left), with involucral bracts; second-order branching = umbellule of Anthriscus sylvestris (right), with involucels

Flowers of Apiaceae: Caraway (Carum carvi, left); Dill (Anethum graveolens, right)

Fruits of Apiaceae, from left to right: Anthriscus sylvestris, Carum carvi, Angelica sylvestris, Scandix pecten-veneris

Leaves in Campanulaceae: almost linear in Campanula rotundifolia (left – the epithet rotundifolia refers to the basal rosett leaves only); cordate in Phyteuma spicatum (right)

Inflorescences in Campanulaceae: raceme in Campanula rapunculoides (left); spike in Phyteuma spicatum (center); head-like umbel in Jasione montana (right)

Flowers of Campanula persicifolia; lateral view (left) and frontal view (right); stamens already wilted before opening of the flower

Flower of Lobelia erinus, frontal and lateral view

Capsules in Campanulaceae: Campanula persicifolia (left), with distal pores in upright capsules; C. rapunculoides (right), with proximal pores in pendent capsules

Leaves of Asteraceae: Scorzonera hispanica (left); Achillea millefolium (center); Cirsium dissectum (right)

Capitula of Asteraceae: Cichorium intybus (left), with ray florets only; Tripleurospermum maritimum (center), with ray florets and disk florets; Cirsium oleraceum (right), with disk florets only

Closeup of the rim of a capitulum of Helianthus annuus (Asteraceae); spreading stigma branches visible in some florets in the foreground

Longitudinal section of a capitulum of Leucanthemum vulgare (Asteraceae)

Florets of Leucanthemum vulgare: ray floret(left) and two disk florets, in male phase (center) and in female phase (right)

Fruiting capitulum of Senecio inaequidens (Asteraceae)

additional images in preparation ...

additional images in preparation ...