1. Two molecules that can cross a lipid bilayer without help from membrane proteins are O2 and CO2. What properties allow this to occur? 2. In the supermarket, produce is often sprayed with water. Explain why this makes vegetables look crisp. 3. Name the molecules that conserve most of the energy from the citric acid cycle’s redox reactions. How is this energy converted to a form that can be used to make ATP 4.When making bread, why does the dough rise? 5. A plant is submerged in water, and bubbles start rising around it. Where do the bubbles come from? 1. A chicken has 78 chromosomes in its somatic cells. How many chromosomes did the chicken inherit from each parent? How many chromosomes are in each of the chicken’s gametes? (3 points) 2. An mRNA has the sequence 5´-AUGAAAUCCUAG-3´. What is the template DNA strand for this sequence? (3 point) 3. 5´-TACTTTAGGATC-3´ 4. 5´-ATGAAATCCTAG-3´ 5. 5´-GATCCTAAAGTA-3´ 6. 5´-TACAAATCCTAG-3´ 7. 5´-CTAGGATTTCAT-3´ 3. Order the four steps in eukaryotic gene expression given below from beginning to end. (3 point) (1) Pre-mRNA is processed to make mRNA. (2) Ribosomes translate the mRNA message to make proteins. (3) mRNA is transported to the cytoplasm. (4) DNA is used as a template make pre-mRNA. 1. 1; 4; 3; 2
