Reading a Grade 3 Fact Text
RI.3.10
Read the text, then answer the questions.
Why Bread Rises
Yeast is alive. It is a fungus, and each grain of dried yeast holds millions of cells waiting for water. Add warm water and the cells wake up. They begin to feed on the sugars in the flour. As they feed, they give off carbon dioxide gas. The gas cannot escape, because kneading the dough has built a stretchy web of gluten that traps it. Thousands of tiny bubbles form, and the dough swells. In the oven, two things happen. The trapped gas expands in the heat, so the loaf rises further. Then the heat kills the yeast and sets the gluten, and the bubbles are locked in place. That is why bread has holes in it.
- 1. What traps the gas in the dough?
- 2. What kind of living thing is yeast?
- 3. What is the author's purpose, and how do you know?
- 4. What gas does yeast give off?
Morse Code
Morse code turns every letter into a pattern of short and long signals: dots and dashes. The commonest letters were given the shortest patterns. E is one dot. T is one dash. Q, which is rare, is dash-dash-dot-dash. Because of that choice, an average message is much shorter than it would be otherwise. A message can be sent as sound, as light, or as taps on a pipe. That is why it survived so long: it needs almost no equipment. Timing carries the meaning. A dash is three times as long as a dot. The gap between letters is three dots long, and between words, seven. SOS was chosen because it is easy to recognise: three dots, three dashes, three dots.
- 1. What is the author's purpose, and how do you know?
- 2. What is the Morse pattern for SOS?
- 3. What is the main idea of this text, and which details support it?
- 4. The author says Morse survived a long time. What reason is given?
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