The colour of the fruit of tomato plants is determined by alleles of the same gene. A tomato plant with red fruit was crossed with a tomato plant with yellow fruit. Of the offspring, 26 plants had red fruit and 24 had yellow fruit. Three explanations were suggested. 1 Both parents were homozygous. 2 One parent had two recessive alleles. 3 One parent was heterozygous. Which explanations are correct?

Which statement about dominant and recessive alleles is not correct?

The genotype for the height of an organism is written as Tt. What conclusion may be drawn?

In a large family, half the children were blood group A and half were blood group B. If the father was blood group O…

The list shows some changes that may occur in a lake that is polluted with nitrogen-containing fertiliser. 1 Concentr…

Which substances are present in breast milk but not in bottled milk made from milk powder?

What are found in plant cells but not in animal cells? 1 cell membrane 2 nucleus 3 cell wall 4 chloroplast