美国医学预科留学有哪些大学可以选？
自从新冠疫情爆发后，医学变成了大热专业之一，申请医学院的学生人数大幅增长。根据美国医学院协会（AAMC）的数据，就在2021-2022这个申请季，全美申请医学院的学生人数较前一年增长了18%，达到62,443人。入学的...
CIE A Level Biology复习笔记8.1.1 Circulatory Systems
Closed Double Circulatory System The need for a circulatory system The cells of all living organisms need a constant supply of reactants for metabolism, e.g. oxygen and glucose Single celled organi...
CIE A Level Biology复习笔记7.2.7 Phloem: Mass Flow
Phloem: Mass Flow The Mass Flow Hypothesis was the model initially used to explain the movement of assimilates in the phloem tissue The mass flow hypothesis was modelled by Ernst Münch in 1930. His...
CIE A Level Biology复习笔记7.2.6 The Sucrose Loading Mechanism
The Sucrose Loading Mechanism Assimilates such as sucrose are transported from source to sink through the phloem sieve tubes Carbohydrates are generally transported in plants in the form of sucrose...
CIE A Level Biology复习笔记7.2.5 Movement in the Phloem
Movement in the Phloem Although translocation could refer to the transport of substances in the xylem and phloem, as it means ‘moving from one place to another,’ it is more commonly connected with ...
CIE A Level Biology复习笔记7.2.4 Xerophytic Plant Leaf Adaptations
Xerophytic Plant Leaf Adaptations Xerophytes (from the Greek xero for ‘dry’) are plants that are adapted to dry and arid conditions Xerophytes have physiological and structural (xeromorphic) adapta...
CIE A Level Biology复习笔记7.2.3 Water & the Transpiration Pull
Water & the Transpiration Pull The movement of water Water has unique properties it is polar hydrogen bonds form between the water molecules Water moves from the roots to the leaves because of ...
CIE A Level Biology复习笔记7.2.2 Transpiration in Plants
Transpiration Explained The movement of water through a plants xylem is largely due to the evaporation of water vapour from the leaves and the cohesive and adhesive properties exhibited by water mo...
CIE A Level Biology复习笔记7.2.1 Water & Mineral Ion Transport in Plants
Water & Mineral Ion Transport: Pathways & Mechanisms Within a plant mineral ions and organic compounds (eg. sucrose) are transported by being dissolved in water. The dissolved mineral ions ...
CIE A Level Biology复习笔记7.1.4 Phloem Sieve Tube Elements
Phloem Sieve Tube Elements & Companion Cells: Structure & Function The function of phloem tissue in a plant is to: Transport organic compounds (assimilates), particularly sucrose, from the ...
CIE A Level Biology复习笔记7.1.3 Xylem Vessels Elements
Xylem Vessel Elements: Structure & Function The functions of xylem tissue in a plant are: Vascular tissue that transports dissolved minerals and water around the plant Structural support Food s...
CIE A Level Biology复习笔记7.1.2 Xylem & Phloem Distribution
Xylem & Phloem Distribution Xylem The functions of xylem tissue in a plant are: Vascular tissue that carries dissolved minerals and water up the plant Structural support Food storage Xylem tiss...
