Chondrichthyes

High school (ages 12+)
Animals & Nature

Name:

Date:

Step 1 · Read the article

Open the article and read it at the level above. Then answer the questions below in your own words.

https://smallwhale.org/articles/chondrichthyes

Write what each word means, using the article.

Do not copy the article. Write two things you learned, the way you would explain them to a friend.

Answers below are taken from the article’s stored facts, so they match what the student read.

1. What is the scientific name?Chondrichthyes
2. What makes Chondrichthyes different from other fish?Chondrichthyes have skeletons made of cartilage instead of bone, which makes them lighter and more flexible.
3. Why do sharks have placoid scales?The tiny tooth‑like scales, called placoid scales, help sharks swim faster by reducing drag and making their skin smoother.

Placoid Scales: Tooth-like dermal denticles providing hydrodynamic efficiency and protection, characteristic of chondrichthyans.
Ampullae of Lorenzini: Electroreceptors enabling detection of weak electrical fields produced by prey, crucial for hunting.
Benthic Zone: The ecological region at the lowest level of a body of water, including the sediment surface and some sub-surface layers.
Pelagic Zone: The open ocean water column, away from the coast and seabed, inhabited by many shark and ray species.