Biology in the Real World
Why do onions make you cry?
Cutting onions releases a gas that reacts with your eyes and forms a mild acid, making you tear up.
Where is DNA found in prokaryotic cells?
In the cytoplasm
Which two fruits did we use in our lab?
What programming language is named after a type of snake?
Python
Brasilia
Why do your muscles get sore after exercise?
Tiny tears form in your muscles when you work out. As they heal, you feel soreness. This helps them grow stronger.
What is the name of the protein that wraps DNA?
Histone
What everyday ingredient is often used to break open cell membranes in a simple DNA extraction experiment?
Dish soap
(They break cell and nuclear membranes(lipids) → Release DNA)
What phenomenon causes a straw to look bent when it’s placed in a glass of water?
Refraction
What planet is named after the Roman God of War
Mars
How do vaccines protect us from viruses?
Vaccines train your immune system to recognize a virus so your body can fight it quickly next time.
The two strands of a DNA molecule are held together by these weak bonds between complementary nitrogen bases. What is this bond?
Hydrogen bond
This lab machine spins samples at high speed to separate components based on density. What is the name of this lab machine?
Centrifuge
Name a Mars Rover
Sojourner
Spirit (MER-A)
Opportunity (MER-B)
Curiosity
Perseverance
Zhurong (China, CNSA)
Rosalind Franklin (ESA, not yet launched)
What animal can regrow its limbs?
Axolotl / starfish
Why do leaves change color in the fall?
When there’s less sunlight, plants stop making green chlorophyll. Other pigments like carotenoids (yellow/orange) and anthocyanins (red/purple) become visible.
This theory establishes that mitochondria and chloroplasts may have been free-living bacteria that we have absorbed through symbiosis in early eukaryotic cells. What is the name of this theory?
endosymbiotic theory
Why do we add cold alcohol in the DNA extraction lab? (2 reasons)
1. DNA insoluble in alcohol (less polar)→ Clump in the boundary area
2. DNases less active at cold temperature - Prevent DNA from degrading
There was an old military project called "Rods From God" that wanted to use big metal rods the size of telephone poles to hit enemies. What were these rods made out of?
Tungsten
Name 3 books by John Green
Why do we breathe faster when we exercise?
Our muscles need more oxygen to make energy, and we breathe faster to take in oxygen and remove extra carbon dioxide
What is the name of the sugar found in DNA structure?
deoxyribose
What is the role of salt in the DNA extraction lab? (Only detailed response will be accepted; explain the procedure)
Salt splits into sodium ions (Na⁺) and chloride ions (Cl⁻) Positively charged sodium ions (Na⁺) neutralizes negative charges of phosphate groups → Reduce repulsion → DNA strands start sticking together
What is the fastest-moving object humans have ever made?
The Parker Solar Probe
What famous film trilogy was directed by the Wachowski sisters?
The Matrix