In western Himalayas, the Betula trees usually occur in:? January 7, 2020 BILAL KHATTAK0 A.Tropical zone B.Sub-tropical zone C.Alpine zoneD.Temperate zoneundefined
Submerged hydrophytes have well developed:? January 6, 2020 BILAL KHATTAK0 A.Vascular system B.Aerenchyma C.Root systemD.Stomaundefined
Which one of the following factors is biotic?? January 6, 2020 BILAL KHATTAK0 A.Photoperiod B.CO2 content to the soil C.Texture and porosity of soilD.Rainfallundefined
Which of the following does not have stomata?? January 4, 2020 BILAL KHATTAK0 A.Hydrophytes B.Submerged hydrophytes C.XerophytesD.Mesophytesundefined
The mangrove plants are generally characterised by:? January 2, 2020 BILAL KHATTAK0 A.Mircophylly B.Pneumatophores and vivipary C.Absence of aerenchymaD.Poor water storageundefined
Special character of hydrophyte is:? January 2, 2020 BILAL KHATTAK0 A.Small spiny stem B.Soft and mucilagenous stem C.Thick and large leafD.None of the aboveundefined
The composition of soil air is affected by:? January 1, 2020 BILAL KHATTAK0 A.Pore size B.Soil organisms C.Type of rootsD.All of theseundefined
When a plant of hot climate is transferred to colder regions, it gets an injury called:? December 31, 2019 BILAL KHATTAK0 A.Chilling B.Thermal death C.DesiccationD.Freezingundefined
The percentage of argon in the atmosphere is:? December 29, 2019 BILAL KHATTAK0 A.About 1% B.0.35% C.0.90%D.3%undefined
Relative to shoots, the roots can be very massive in plants of:? December 26, 2019 BILAL KHATTAK0 A.Deserts B.Lakes and ponds C.Mixed temperate forestsD.Mixed tropical forestsundefined