Our planet has existed for 4.5 billion years, and it has been a busy few eons. Here are the 25 biggest milestones in Earth’s history. From leaps forward in evolution to devastating asteroid impacts, these were the turning points that shaped our world. Source of information: http://www.bbc.com/earth/bespoke/story/20150123-earths-25-biggest-turning-points/
Some bacteria are resistant to many different antibiotics; they are multidrug-resistant. Multidrug-resistant bacteria can be difficult to treat and facilitates spread of antibiotic resistance. Why multidrug-resistant bacteria are problematic: Infections with multidrug-resistant bacteria are hard to treat since few or even no treatment options remain. In some cases health care providers have to use antibiotics that are more toxic for the patient.Multidrug-resistance facilitates spread of antibiotic resistance. When multidrug-resistance plasmids are transferred to other bacteria, these become resistant to many antibiotics at once. In environments…
As the human population has swelled to 7.5 billion, our species’ massive footprint on planet Earth has had a devastating impact on mammals, birds, reptiles, insects, and marine life. We’ve driven thousands of species to the edge of extinction through habitat loss, overhunting and overfishing, the introduction of invasive species into new ecosystems, toxic pollution, and climate change. In the past 40 years, the number of wild animals has plunged 50 percent, a 2014 study found. And the World Wildlife Fund (WWF) estimates that populations…
Global climate change has already had observable effects on the environment. Glaciers have shrunk, ice on rivers and lakes is breaking up earlier, plant and animal ranges have shifted and trees are flowering sooner. Effects that scientists had predicted in the past would result from global climate change are now occurring: loss of sea ice, accelerated sea level rise and longer, more intense heat waves. Scientists have high confidence that global temperatures will continue to rise for decades to come, largely due to greenhouse gases…
Biologists estimate there are between 5 and 15 million species of plants, animals, and micro-organisms existing on Earth today, of which only about 1.5 million have been described and named. The estimated total includes around 300,000 plant species, between 4 and 8 million insects, and about 50,000 vertebrate species (of which about 10,000 are birds and 4,000 are mammals). Habitat destruction through human activity is mainly for the purpose of harvesting natural resources for industrial production and urbanization. Clearing habitats for agriculture is the principal…
Biodiversity loss, also called loss of biodiversity, a decrease in biodiversity within a species, an ecosystem, a given geographic area, or Earth as a whole. Biodiversity, or biological diversity, is a term that refers to the number of genes, species, individual organisms within a given species, and biological communities within a defined geographic area, ranging from the smallest ecosystem to the global biosphere. Likewise, biodiversity loss describes the decline in the number, genetic variability, and variety of species, and the biological communities in a given…
Planet Earth doesn’t have a birth certificate to record its formation, which means scientists spent hundreds of years struggling to determine the age of the planet. So, just how old is Earth? By dating the rocks in Earth’s ever-changing crust, as well as the rocks in Earth’s neighbors, such as the moon and visiting meteorites, scientists have calculated that Earth is 4.54 billion years old, with an error range of 50 million years. If the entire history of the Earth was compressed into a single…
Secondary 3 Science (Biology) Mini-project on Chinese Medicinal Herbs Information sheet Class 3A Class No. and Name Yeung Hoi Ching (31), Yeung Yan Ki (32), Yim Yu Tin (33), Yip Cheuk hin (34) Year: 2018-2019 Instruction: Type in useful information in the space provided. Chinese name: 北美金縷梅 Family Name (科名): Hamamelidaceae Scientific name (學名): Hamamelis virginiana Common name (俗名): Witch Hazel 習性：落葉大灌木，莖幹由植株基部長出，枝條密生，植株高度可以生長至六米高，極少數個體有時可以長至十米左右 Growth habit: It is a small, deciduous tree growing up to 6 m (rarely to 10 m) tall, often with a dense…
Secondary 3 Science (Biology)Mini-project on Chinese Medicinal Herbs Information sheet Class 3DClass No. and Name: (23) Tso Man Ying (24) Tu Hoi Yan (25) Wong Cho Kei (26) Wong EdisonYear: 2018-2019 Instruction: Type in useful information in the space provided. Chinese name: 毛喉牛奶菜 Family Name(科名) 蘿藦科 Asclepiadaceae Scientific name(學名) Marsdenia lachnostoma Common name(俗名) Hairy-throat Condorvine 習性: 生亞灌木。 Growth habit: Scandent subshrubs 葉： 圓形或近心形，端部銳尖，背面蒼白或白霜。Leaf: Base rounded or subcordate, apex acute or obtuse, abaxially pale or glaucous. 花： 大部分花為黃色，中間為白色，5月開花。 Flower: Pale yellow Flowering in May 果： 5月成熟 Fruit: Matured…
Secondary 3 Science (Biology) Mini-project on Chinese Medicinal Herbs Information sheet Class 3B Class No. and Name Sze Hugo (24) Year: 2018-2019 Instruction: Type in useful information in the space provided. Chinese name: 海島十大功勞 Family Name (科名): BERBERIDACEAE Scientific name (學名): Mahonia oiwakensis Hayata Common name (俗名): Island Mahonia 習性： 灌木 Growth habit: shrub 葉： 葉長圓狀橢圓形，長15-42厘米，寬8-15厘米 Leaf: The leaf is in an oval shape. Its length is 15-42 cm and its width is 8-15 cm 花： 繁華黃花，有孔雀開屏的氣焰 Flower: It is yellow 果： 果初生粉綠，成熟轉成粉紫藍 Fruit: They…