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Why do large organisms need specialised exchange systems and what are the features of an efficient exchange surface?

Large organisms have-High metabolic activity (used in movement, respiration, reproduction etc)Large distance between cells and the incoming oxygen that they requireA very small surface area to volume ratio m...
AJ
Answered by Abigail J. • Biology tutor
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What is the use of membranes within the cell?

Membranes within the cell are used in compartmentalisation for numerous reasons- one being to allow processes to occur separately in different organelles without interacting and affecting other processes, wh...
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Answered by Abigail J. • Biology tutor
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In humans, cystic fibrosis is caused by a recessive allele, f. A man and a woman are both heterozygous for the cystic fibrosis allele. What is the probability that they will produce a girl who has cystic fibrosis?

The genotype for someone heterozygous for the cystic fibrosis allele would be Ff . Thus the father’s genotype (including sex chromosomes) would be FfXY and the mother’s would be FfXX . In order to work out t...
YM
Answered by Yasmin M. • Biology tutor
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What are the main functions of the liver?

The liver has 4 main functions. In detoxification, toxins (poisonous chemicals produced by living cells or organisms) are broken down, often by enzymes found in the liver, for example catalase which breaks d...
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Answered by Abigail J. • Biology tutor
4391 Views

Describe and explain some of the adaptations xerophytes have against living in extreme dry conditions.

Xerophyte adaptations include: Curled leaves - create a micro-climate of more humid surrounding air, hence less water is lost to the dry surroundings. Small hairs on leaves - slow surrounding air flow, there...
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Answered by Marlon J. • Biology tutor
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