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Agrobacterium tumefaciens

Agrobacterium tumefaciens   Quick reference

A Dictionary of Genetics (8 ed.)

Reference type:
Subject Reference
Current Version:
2014
Subject:
Science and technology, Life Sciences
Length:
243 words

...ORFs tRNAs rRNAs CC 2,841 2,789 40 2 LC 2,076 1,882 13 2 pAt 543 550 0 0 pTi 214 198 0 0 Strains of A. tumefaciens carrying the plasmid may be artificially genetically engineered to introduce foreign genes of choice into plant cells and then, by growing the cells in tissue culture, whole plants can be regenerated, every cell of which contains the foreign gene. See Appendix A , Prokaryotae, Bacteria, Proteobacteria; Appendix C , 1907, Smith and Townsend; 1981, Kemp and Hall; 2001, Wood et al .; Appendix E , Species Web Site; Ti plasmid...

Spiders

Spiders   Reference library

The New Encyclopedia of Insects and their Allies (3 rev. ed.)

Reference type:
Subject Reference
Current Version:
2009
Subject:
Science and technology, Life Sciences
Length:
8,259 words
Illustration(s):
11

...for 2–5 years, and theraphosids (tarantulas) in captivity may live up to 25 years. During a lifetime, they typically grow through 4–12 molts of the exoskeleton before finally becoming adult. Adult males can usually be distinguished from adult females by their smaller size, slimmer body, and relatively longer legs. This sexual dimorphism is most obvious in many tropical web‐builders, such as the golden orb‐weavers ( Nephila species), where the females may be giants – up to 45mm (1.8in) in body length – and the males are frequently a dwarfish 4–8mm (0.20.3in)....

Scorpionflies

Scorpionflies   Reference library

The New Encyclopedia of Insects and their Allies (3 rev. ed.)

Reference type:
Subject Reference
Current Version:
2009
Subject:
Science and technology, Life Sciences
Length:
1,378 words
Illustration(s):
1

...true, or common, scorpionflies are widely distributed. About 15–20mm (0.6–0.8in) long, they are usually yellowish‐brown with brownish bands and spots on the wings. Panorpa communis is a very common species throughout Europe, with a wingspan of 30mm (1.2in). The snow scorpionflies, characterized by their vestigial wings, are found in Europe and North America, where they live and feed on moss. These unusual insects are often found on the surface of the snow in winter, and are 2–5mm (0.08–0.2in) long and dark‐colored. The hanging scorpionflies are so called for...

Platypus

Platypus   Reference library

The Encyclopedia of Mammals (3 ed.)

Reference type:
Subject Reference
Current Version:
2007
Subject:
Science and technology, Life Sciences
Length:
1,277 words
Illustration(s):
2

...female 39–55cm (15.4–21.7in); bill length average male 5.8cm (2.3in) female 5.2cm (2in); tail length male 10.5–15.2cm (4.1–6in) female 8.5–13cm (3.3–5.1in); weight male 1–2.4kg (2.2–5.3lb) female 0.7–1.6kg (1.5–3.5lb). Coat Dark brown back, silver to light brown underside with rust brown midline, especially in young animals, which have the lightest fur. Short, dense fur (about 1cm/0.4in depth). Light patch below eye/ear groove. Breeding Gestation period not known (probably 2–3 weeks). Incubation not known (probably about 10 days). Longevity 10 or...

Rotifers, or Wheel Animalcules

Rotifers, or Wheel Animalcules   Reference library

The Encyclopedia of Underwater Life

Reference type:
Subject Reference
Current Version:
2007
Subject:
Science and technology, Life Sciences
Length:
660 words
Illustration(s):
1

...of water and their populations may rise and fall rapidly. They are crucial members of numerous aquatic food webs. Soil-dwelling rotifers aid soil breakdown. Andrew Campbell Factfie-Rotifers, or Wheel Animalcules Phylum: Rotifera Classes: Monogononta, Digononta, Bdelloidea About 1,800 species in 100 genera and 3 classes. Distribution Worldwide, mainly freshwater, some marine, and damp soils. Fossil record None. Size Microscopic, 0.04–2mm (0.002–0.08in). Features Solitary or colonial; body cavity a pseudocoel (now described as blastocoelomate); head bears...

Stoneflies

Stoneflies   Reference library

The New Encyclopedia of Insects and their Allies (3 rev. ed.)

Reference type:
Subject Reference
Current Version:
2009
Subject:
Science and technology, Life Sciences
Length:
963 words
Illustration(s):
1

...important part of the freshwater food web, providing food for many other insects and fish. Since stoneflies are very sensitive to pollution, they are used by scientists as indicators of water quality. Factfile‐Stoneflies Class: Insecta Subclass: Neoptera Order: Plecoptera 2,000 species in 15 families, divided between 2 suborders: Arctoperlaria (11 families) and Antarctoperlaria (4 families). DISTRIBUTION Worldwide except Antarctica, especially in temperate climes. SIZE Delicate, medium‐sized; body length 3–50mm (0.1–2in). FEATURES Cylindrical body,...

Limpkin

Limpkin   Reference library

The New Encyclopedia of Birds

Reference type:
Subject Reference
Subject:
Science and technology, Life Sciences
Length:
635 words
Illustration(s):
3

...arid brush (as in W Indies). Size Length 56–71cm (22–28in); weight 0.9–1.3kg (22.9lb). Plumage Dark olive-brown with bronze to greenish iridescence on upperparts, foreparts broadly streaked with white; sexes alike. Voice Noisy; loud wails, screams, and assorted clucks, heard mostly at night. Nest Shallow, made of rushes or sticks just above the waterline in marshes, or else in bushes or trees. Eggs Usually 5–7, pale buff, blotched and speckled with light brown; average size 60 x 44mm (2.4 x 1.7in). Incubation about 27 days. Diet Mainly large snails and...

Booklice and Webspinners

Booklice and Webspinners   Reference library

The New Encyclopedia of Insects and their Allies (3 rev. ed.)

Reference type:
Subject Reference
Current Version:
2009
Subject:
Science and technology, Life Sciences
Length:
1,200 words
Illustration(s):
2

...species in 8 families. Size: Small to medium‐sized; 5–12mm (0.20.5in) long. Features: Elongated, cylindrical body adapted for living in tubular silk tunnels; antennae with 12–32 segments; eyes kidney‐shaped; no simple eyes (ocelli); biting mouthparts; males have 2 pairs of long, narrow wings; all females (and males of some species) wingless; legs short, thick, with 3‐segmented tarsi; swollen basal tarsal segment of forelegs bears silk gland; hind femora enlarged; abdomen 10‐segmented, with 2‐segmented cerci at tip. Life cycle: Nymphs adultlike, without...

Whistlers

Whistlers   Reference library

The New Encyclopedia of Birds

Reference type:
Subject Reference
Subject:
Science and technology, Life Sciences
Length:
639 words
Illustration(s):
3

...Australasia and SE Asia Habitat All habitats from rainforest to arid scrub. Size Length 11–26cm (4–10in); weight: 12–80g (0.5–3oz). Plumage Gray or brown, but adult males of many species brightly colored. Voice Distinctive, melodious, whistling or bell-like songs; harsher contact calls. Nest Carefully woven cups of grasses, lichen, twigs, and bark chips, held together by spider's webs, usually placed in fork of a tree or shrub. Eggs 2–4, white to buff, usually with a ring of brown to gray blotches at the larger end. Incubation period 14–18 days; nestling...

Long-tailed Tits

Long-tailed Tits   Reference library

The New Encyclopedia of Birds

Reference type:
Subject Reference
Subject:
Science and technology, Life Sciences
Length:
1,001 words
Illustration(s):
3

...Tits Order: Passeriformes Family: Aegithalidae 7 species in 2 genera: bushtit ( Psaltriparus minimus ), Long-tailed tit ( Aegithalos caudatus ), Black-browed tit ( A. iouschistos ), Black-throated tit ( A. concinnus ), White-cheeked tit ( A. leucogenys ), White-necklaced tit ( A. fuliginosus ), White-throated tit ( A. niveogularis ). Distribution Europe to Asia; N and C America Habitat Mainly forest and woodland Size Length 9–14cm (3.5–5.5in); weight 5–9g (0.20.3oz). Plumage Chiefly black, gray, white, and brown, with pink in the...

Gnatcatchers

Gnatcatchers   Reference library

The New Encyclopedia of Birds

Reference type:
Subject Reference
Subject:
Science and technology, Life Sciences
Length:
921 words
Illustration(s):
2

...the Caribbean. Habitat In forest, woodland, and scrub, including quite dry areas. Size Length 9–12cm (3.7–4.8in); weight about 6–10g (0.25–0.4oz); slight difference between sexes in some species. Plumage Gray and black (gnatcatchers); brown with pale underparts (gnatwren). Voice Simple whistles and calls, chips, and rather nasal soft notes. Nest Substantial pile of dead leaves with deep cup, or neat saucer on branch. Eggs 2–6; pale ground (blue. olive, or stone) with a few darker dots and speckles. Diet Insects and other arthropods. Conservation status The...

Millipedes and Centipedes

Millipedes and Centipedes   Reference library

The New Encyclopedia of Insects and their Allies (3 rev. ed.)

Reference type:
Subject Reference
Current Version:
2009
Subject:
Science and technology, Life Sciences
Length:
3,227 words
Illustration(s):
8

...15 pairs of legs; in varied habitats. Symphylans Class Symphyla 200 species of small, pale herbivores, 2–10mm (0.08–0.4in) long, with 12 leg‐bearing segments (but extra tergites or back plates) and 3 pairs of mouthparts resembling those of insects; eyeless. In soil and leaf mould, under stones, in rotting wood. Pauropods Class Pauropoda 700 species of tiny, soft‐bodied scavengers, 0.5–2mm (0.02–0.08in) long, with 9 leg‐bearing segments (but fewer tergites), 2 pairs of mouthparts, branched antennae; eyeless. In soil and leaf mold. Helen J. Read / John Lewis HJR...

Vangas, Wattle-eyes, and Batises

Vangas, Wattle-eyes, and Batises   Reference library

The New Encyclopedia of Birds

Reference type:
Subject Reference
Subject:
Science and technology, Life Sciences
Length:
694 words
Illustration(s):
2

...of the majority are neat cups made from small leaves, roots, fibers, and bark, all bound to the supporting branches with spiders' web and often covered in lichen. In marked contrast, the Sickle-billed vanga builds a crowlike nest of sticks. Alan Kemp / Llewellyn G. Grimes Factfile-Vangas, Wattle-eyes, & Batises Order: Passeriformes Family: Vangidae 41 species in 14 genera (vangas 15 species in 11 genera; wattle-eyes 10 species in 2 genera; batises 16 species in 1 genus). Species include: Chabert vanga ( Leptopterus chabert ), Helmet vanga ( Euryceros...

Roundworms

Roundworms   Reference library

The Encyclopedia of Underwater Life

Reference type:
Subject Reference
Current Version:
2007
Subject:
Science and technology, Life Sciences
Length:
1,876 words
Illustration(s):
2

... Phyla: Nematoda About 25,000 species in 2 classes. Roundworms, eelworms, threadworms, or nematodes Phylum Nematoda About 25,000 named species in 2 classes, but many may remain to be discovered. Distribution: worldwide; mostly free living in damp soil, freshwater, marine: some parasites of plants and animals. Fossil record: sparse; around 10 species recognized in insect hosts from Eocene and Oligocene (54–26 million years ago). Size: from below 0.05mm to about 1m (0.02in–3.3ft) but mostly between 0.1 and 0.2mm (0.04–0.008in). Features: round unsegmented worms...

Cormorants

Cormorants   Reference library

The New Encyclopedia of Birds

Reference type:
Subject Reference
Subject:
Science and technology, Life Sciences
Length:
2,056 words
Illustration(s):
3

...suffer from the heat and regulate their temperature by fluttering throat skin, panting, and exposing their webs so as to radiate heat. Many species leave the nest before they can fly, forming crèches in the manner of pelicans. The shortest period before flight is about 5 weeks, in the Crowned cormorant. Breeding success, as judged by the ratio of chicks fledged to eggs laid, varies from 20–60 percent, and cormorants rear on average between 0.3 and 2.5 young per successful breeding attempt. Few cormorants live for more than 10–15 years. Natural mortality...

Bugs

Bugs   Reference library

The New Encyclopedia of Insects and their Allies (3 rev. ed.)

Reference type:
Subject Reference
Current Version:
2009
Subject:
Science and technology, Life Sciences
Length:
8,981 words
Illustration(s):
5

...mirids is Hadronema uhleri , which lives and scavenges exclusively in spiders' webs. The genus Helopeltis (Bryocorinae) is a pest of cultivated plants in tropical Africa and the Indo‐Malayan region. The Australian Tytthus mundulus (Phylinae) preys on insect eggs and is used to control the Sugar‐cane hopper ( Perkinsiella saccharicida ) in Hawaii. The Tingidae, or lace bugs, contain 1,900 species worldwide in 3 subfamilies. They range in length from 2 to 8mm (0.08–0.3in), and most species are characterized by the dense reticulate or lacelike network...

Monarch Flycatchers

Monarch Flycatchers   Reference library

The New Encyclopedia of Birds

Reference type:
Subject Reference
Subject:
Science and technology, Life Sciences
Length:
1,037 words
Illustration(s):
2

...and woodland Size Length 12–30cm (5–12in), including tail; weight 5–40g (0.2–1.4oz). Plumage Often metallic black or gray, or chestnut with white underparts; sexes differ in appearance in some species. Voice Harsh or whistling calls Nest Cup-shaped, often decorated with lichen, moss, bark, or spiders' webs. Eggs 1–5; white, with red-brown spots or blotches. Diet Most species eat insects; a few also take fruit. Conservation status In total, 36 species are listed by the IUCN. 2 species – the Maupiti monarch ( Pomarea pomarea ) and the Guam flycatcher (...

Sunbirds, Spiderhunters, and Sugarbirds

Sunbirds, Spiderhunters, and Sugarbirds   Reference library

The New Encyclopedia of Birds

Reference type:
Subject Reference
Subject:
Science and technology, Life Sciences
Length:
2,150 words
Illustration(s):
2

...embedded or suspended; side entrance is often covered with a porchlike projection; often decorated or held together by spider webs. Nests of spiderhunters and sugarbirds are cup-shaped. Eggs 2, sometimes 3, whitish or bluish white with dark spots, blotches, or streaks. Incubation period 13–15 days (17 days in sugarbirds); nestling period 14–19 days. Diet Flower nectar and arthropods, especially spiders; rarely fruit. Conservation status 2 sunbirds – the Amani sunbird ( Anthreptes pallidigaster ) of East Africa and the Elegant sunbird ( Aethopyga duyvenbodi ) of...

Gannets and Boobies

Gannets and Boobies   Reference library

The New Encyclopedia of Birds

Reference type:
Subject Reference
Subject:
Science and technology, Life Sciences
Length:
2,299 words
Illustration(s):
5

...species, divisible into three allospecies. Distribution N Atlantic, South Africa, Australasia (gannets); pantropical oceans (boobies). Habitat Breed mainly on islands and isolated rocks. Size Length 60–85 cm (23.6–33.5 in); wingspan 1.41–1.74 m (4.6–5.7 ft); weight 0.8–3.6 kg (2–8 lb). Females larger than males, or sexes similar. Plumage Adults of all species have white underparts (except for some races of the Red‐footed booby), with variable amount of black or brown above; most have brightly colored bills, faces, and feet. Voice Raucous or sonorous...

Pheasants and Quails

Pheasants and Quails   Reference library

The New Encyclopedia of Birds

Reference type:
Subject Reference
Subject:
Science and technology, Life Sciences
Length:
3,915 words
Illustration(s):
6

...the breeding season, however, the cocks become solitary and pugnacious. Each adult male returns to a place he occupied in previous years and establishes his territorial rights, threatening intruders and calling loudly to advertise his presence. Territories are small, from 0.05 to 0.5ha (0.1–1.2 acres), and center on clearings in forest or scrub. These territories tend to be clumped together, so that males are aware of each other's close proximity. Occasionally a junior male will challenge a senior neighbor, and a long and violent battle ensues. The combatants...

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