Btec Applied Science Unit One Biology – Complete Questions and Answers 2023

Btec Applied Science Unit One Biology – Complete Questions and Answers 2023. What is the function of the plasmodestmata? correct answerTo allow materials to pass through the cell wall What is the function of the amyloplasts? correct answerStarch synthesis and storage Name three organelles which are only in plant cells correct answerVacuole, chloroplasts, cell wall Define eukaryotic cells correct answerAre part of a multicellular organisms Define prokaryotic cells correct answerAre unicellular organisms Name two differences between eukaryotic and prokaryotic cells? correct answerEukaryotic has a nucleus but prokaryotic doesn't my eukaryotic has a membrane bound organelles while prokaryotic doesn't What two dyes are used to show gram positive and gram negative bacteria? correct answerCrystal violet and safranin Describe the difference between gram positive and gram negative? correct answerGram negative has thin cell walls so the ethanol washes out the crystal violet, so they appear safranin pink. Gram positive appears purple Describe the key features of a sperm cell? correct answerAcross one to penetrate the egg, tail for swimming, lots of mitochondria for energy Describe the features of egg cells? correct answerHormones to attract the speed, zona pellucuda to protect the egg, corona radiate to supply protein to developing foetus What is TEM? correct answerTransmission electron microscope What is SEM? correct answerScanning electron microscope Compare TEM and SEM correct answerTEM produces images of thin slices of material whereas SEM looks at the surface topography. Both are very magnified compared to the light microscopes and require dead samples. Describe how a light microscope works correct answerLight microscopes use visible light and magnifying lenses to observe small objects Describe how an electron microscope works correct answerThey use a beam of electrons in a vacuum with a wavelength of less than 1 nm to visualise the specimen