HS-LS1 From Molecules to Organisms: Structures and Processes

Anchoring Phenomenon:

The largest tree in the world is a giant sequoia (Sequoiadendron giganteum) in California’s Sequoia National Park called General Sherman. General Sherman is tall, standing 274.9 feet (83.8 m) high, and is about 52,500 cubic feet (1,487 m3) in volume—more than half the volume of an Olympic-size pool. Incredibly, this enormous tree started as a small seed, merely 0.16–0.20 inches (4–5 mm) long and 0.04 inch (1 mm) wide.

Driving Question:

How did General Sherman gain its mass if it started from such a tiny seed?

HS-LS2 Ecosystems: Interactions, Energy, and Dynamics

Anchoring Phenomenon:

The ocean has been an important cultural and economic resource for the island country of Japan for thousands of years. Fish constitutes a large portion of the Japanese diet, and Japan consumes millions of tons of fish each year. In recent decades, however, fisheries depletion has become a global issue. Between 1995 and 2011, the total catch in Japan decreased from 6 million to 3.8 million tons. Consequently, Japan decided to increase whaling, reasoning that whales eat fish and krill and were at least somewhat responsible for the decline in fish populations, either directly or indirectly through competition. However, with the increase of whaling, the fish populations began to crash. Scientists set out to better understand why the fish populations declined. In doing so, they discovered that not only did whales influence fish populations, but also their removal contributed to climate change. Students are oriented to whale plumes early in the unit as a potential important factor leading to these disturbances in the ecosystem.

Driving Question:

Why did whaling lead to a collapse in fish populations and contribute to climate change?

HS-LS3 Heredity: Inheritance and Variation of Traits

Anchoring Phenomenon:

Freja Nicholson was a girl from England who enjoyed spending time at the beach and traveling

with her family. Freja had a very light complexion and wore sunscreen when she traveled, but she often went without it when she was at home. She sometimes used tanning beds. At age 14, she had an atypical benign mole removed. Later, her doctors found a cancerous mole. The cancer eventually spread into her lymph nodes. Even though she had a number of lymph nodes removed, by the

time she was 17, the cancer had spread to her breast, armpit, brain, and arm. Freja passed away at the age of 18. Her family has shared her story to help raise awareness of skin cancer in teenagers.

Driving Question:

What caused Freja’s skin cancer?

HS-LS4 Biological Evolution: Unity and Diversity

Anchoring Phenomenon:

Lampsilis mussels, like other mussels, have a complicated life cycle involving a parasitic stage

in which microscopic larvae must reside in living hosts to complete the cycle. For the Lampsilis

mussel, this host is the largemouth bass. This presents a challenge, as the bass do not prey on mussels and therefore have little reason to get close enough for the mussels to deliver their larvae. Amazingly, the mussels have developed lifelike lures to attract the bass. The mussel uses flesh from its mantle that not only looks like the bass’s prey but also moves like them as the mussel twitches its lure. When the bass attacks the lure, a membrane is broken, firing the mussel’s larvae into the

fish’s gills. The parasitic larvae attach and drain nutrition from their host before eventually falling off and settling on the riverbed to complete their life cycle. Typically, this species mimics the small fish prey of the largemouth bass. There are four widespread types of lures in the genus, some of which are stronger mimics of the bass prey than others. The most effective mimics are the darter fish lures, some of which even sport eyespots and what look like gasping mouths. These occur at a higher rate in the population. Amazingly, the mussels have developed these lifelike lures even though they have no eyes and have never seen the fish they are mimicking.

Driving Question:

How did Lampsilis mussels develop lifelike lures over time?

Anchoring Phenomenon

First filmed in Antarctica in 2011, brinicles are underwater icicles that form downward from floating ocean glaciers and, in some cases, extend all the way to the seafloor. In places where the brinicles have reached and begun to spread across the ocean bottom, they have been filmed freezing or killing sea creatures in their path, hence the nickname “icicles of death.” The development of these curious icicles has led to questions about how and why they form.

Driving Question

How and why do brinicles form?

Anchoring Phenomenon

The Hindenburg was an 804-foot-long German airship that used hydrogen gas (H2) to generate its lifting capacity. The airship’s hydrogen was stored in 16 gas cells with a capacity of 7,062,000 cubic feet. It was originally designed to use helium as its lifting gas, but the United States was the only country with helium and refused to sell it to the Germans because of the impending war. The Hindenburg was the last passenger aircraft of the world’s first airline and marked the beginning

and end of transatlantic airships. It was the fastest way to cross the Atlantic in the mid to late 1930s, when the Hindenburg’s passengers could travel from Europe to North and South America

in half the time it would take on the fastest ocean liner. Additionally, the interior was luxurious, with comfortable cabins and an elegant dining room.

On May 6, 1937, the Hindenburg arrived at the Lakehurst Naval Air Station in New Jersey hours behind schedule because of inclement weather with wind, rain, and possibly lightning.  Landing in these conditions was against regulations, but by the time the Hindenburg began its landing, the weather was clearing up. The airship seems to have been traveling at a fairly fast speed for its landing, and for some reason, the captain attempted a high landing from about 200 feet. Soon after the mooring lines were set, some eyewitnesses reported a blue glow on top of the Hindenburg, followed by a flame toward the tail section of the craft and an explosion that occurred almost simultaneously. The craft was quickly engulfed in flames, causing it to crash into the ground, killing 35 of the 97 people on board, as well as a crew member on the ground. In what has been estimated as just 32–37 seconds, the great Hindenburg had completely burned. The day after this horrible tragedy, newspapers started speculating about the cause of the disaster.

Driving Question

How and why did the Hindenburg burn so quickly?

Anchoring Phenomenon

Pteropods are sea snails or sea slugs, tiny organisms found in oceans around the world. Some pteropods, known as sea butterflies, have calcareous shells, meaning they contain calcium carbonate. In studies conducted in 2014, scientists found that the shells of pteropods off the West Coast of the United States were severely damaged. Since then, pteropod shell damage has been reported

more on the West Coast than on the East Coast.

Driving Question

What is causing pteropod shells to become damaged more on the West Coast of the United States

than on the East Coast?

Anchoring Phenomenon

In the early 1900s, the Waterbury Clock Company, a watch-making business in Waterbury, Connecticut, employed many women to aid in the creation of new watches. The faces of these watches glowed in the dark because they were painted with self-luminous paint that contained radium. The women, famously known as the Radium Girls, worked tirelessly to paint these watches, making sure to not leave any stray marks on the watch faces. To ensure that their work was meticulous, the women were taught to wet their brushes between their lips to point the tips. As a consequence, the women ingested some of the luminous paint that contained radium. Over time, these women began to experience serious health conditions. In some cases, their jaws deteriorated or simply fell out of place. The Radium Girls also suffered from a variety of other illnesses, which resulted in an

untimely death for many.

Driving Question

Why did the Radium Girls develop such different, yet fatal, illnesses from their work painting watch faces for U.S. radium factories?