Tag: science & technology

Ostrich eggs are the largest single cells among vertebrates, measuring about 15 cm in length and visible to the naked eye. While bird eggs are unusual cases of very large cells, the ostrich egg is notably the biggest.

Mitochondria are called the powerhouse of the cell because they produce ATP through cellular respiration, providing energy for cellular functions. This is a fundamental concept in cell biology.

Ribosomes are the sites of protein synthesis in cells - they translate mRNA into proteins. This is their primary function and why they are found throughout the cell.

Lysosomes contain digestive enzymes that break down waste materials and cellular debris. When a cell is damaged or dying, lysosomes can release these enzymes to break down the cell itself, hence 'suicidal bags'.

Chloroplasts are called the kitchen of the cell because they perform photosynthesis - converting light energy into chemical energy (glucose) for the plant. This is analogous to preparing food in a kitchen.

Chloroplasts contain chlorophyll, the green pigment that gives plants their characteristic color and enables photosynthesis. This is why plants appear green.

Chromoplasts are plastids that contain pigments giving color to plant parts like fruits, flowers, and aging leaves. They synthesize and store pigments such as carotenoids (red, orange, yellow). Chloroplasts contain chlorophyll for photosynthesis (green), leucoplasts store colorless starch/proteins, and chrolophyll is a misspelling of chlorophyll.

The nucleus is called the control room of the cell because it contains the genetic material (DNA) and directs all cellular activities including growth, metabolism, protein synthesis, and reproduction. It regulates gene expression and cell division. Mitochondria produce energy, cell wall provides structure in plants, and 'Cell' is too general.

Gregor Mendel is known as the father of genetics for his pioneering work on inheritance patterns using pea plants. He discovered fundamental laws including dominance, segregation, and independent assortment. The answer has a typo - it should be Gregor, not Johan. H G Khorana contributed to cracking the genetic code, Robert Hooke discovered cells, and Aristotle studied natural philosophy.

Charles Robert Darwin proposed the theory of natural selection in his work 'On the Origin of Species' (1859). Natural selection explains how organisms with favorable traits are more likely to survive and reproduce. Options B, C, D have garbled variations of his name but are incorrect spellings.