A tall plant (Tt) is crossed with a dwarf plant (tt). Out of 64 offspring, how many tall plants are expected?
Answer and explanation
Correct answer: A. 32
- Step 1: Gametes from Tt are T or t, and from tt are t only. Step 2. Offspring are Tt or tt in equal numbers, so half of 64 are tall: 32. Answer: 32. Why not the others: 3:1 comes from Tt x Tt and not every offspring inherits T.
Practise more Cells, Genetics, Ecology and Human Biology.
Free questions with an explanation for every one, and full timed Leaving Cert Ireland mock tests.
More Cells, Genetics, Ecology and Human Biology questions
- Which organelle is the main site of aerobic respiration in an animal cell?
- What is an enzyme?
- How many cells result from one complete round of mitosis in a diploid cell?
- What is osmosis?
- Which tissue carries water and minerals upwards from the roots to the leaves of a plant?
- Which blood cells carry oxygen from the lungs to the tissues?