#2.51
understand why simple, unicellular organisms can rely on diffusion for movement of substances in and out of the cell
#2.52
understand the need for a transport system in multicellular organisms
#2.53
describe the role of phloem in transporting sucrose and amino acids between the leaves and other parts of the plant
#2.54
describe the role of xylem in transporting water and mineral ions from the roots to other parts of the plant
#2.55B
understand how water is absorbed by root hair cells
#2.56B
understand that transpiration is the evaporation of water from the surface of a plant
#2.57B
understand how the rate of transpiration is affected by changes in humidity, wind speed, temperature and light intensity
#2.58B
practical: investigate the role of environmental factors in determining the rate of transpiration from a leafy shoot
#2.59
describe the composition of the blood: red blood cells, white blood cells, platelets and plasma
#2.60
understand the role of plasma in the transport of carbon dioxide, digested food, urea, hormones and heat energy
#2.61
understand how adaptations of red blood cells make them suitable for the transport of oxygen, including shape, the absence of a nucleus and the presence of haemoglobin
#2.62
understand how the immune system responds to disease using white blood cells, illustrated by phagocytes ingesting pathogens and lymphocytes releasing antibodies specific to the pathogen
#2.63B
understand how vaccination results in the manufacture of memory cells, which enable future antibody production to the pathogen to occur sooner, faster and in greater quantity
#2.64B
understand how platelets are involved in blood clotting, which prevents blood loss and the entry of micro-organisms
#2.65
describe the structure of the heart and how it functions
#2.66
explain how the heart rate changes during exercise and under the influence of adrenaline
#2.67
understand how factors may increase the risk of developing coronary heart disease
#2.68
understand how the structure of arteries, veins and capillaries relate to their function
#2.69
understand the general structure of the circulation system, including the blood vessels to and from the heart and lungs, liver and kidneys