Question

breakingnewsenglish
ocean acidification a danger to sharks teeth
1st september 2025
the climate crisis may be posing an existential threat to many species of shark. a new study has revealed that the acidification of the worlds oceans is causing sharks teeth to decay. it is well known in the scientific community that increasing ocean acidity is damaging calcified species like corals, molluscs, and sea urchins. this led marine biologists to research whether shark teeth are at similar risk. lead author of the study, maximilian baum, investigated whether \sharks that swim with their mouths open to ventilate their gills and have constant seawater exposure might also be vulnerable\. he concluded that \even the teeth of apex predators show visible damage under acidified conditions\.
baum and his colleagues analyzed 42 teeth from 10 blacktip reef sharks at an aquarium in germany. they placed the teeth in two separate water tanks for eight weeks. the salt water in one tank had a ph level of 8.2, which is similar to current ocean averages. the water in the other tank was more acidic, with a ph level of 7.3. baum found that the teeth in the more acidic water had \visible surface damage\. this included cracks and cavities, increased root decay, and structural deterioration. he said ongoing damage could impact how sharks feed in the future. such damage could potentially trigger \domino effects\ across the health of many marine ecosystems.
sources: yahoo.com / cnn.com / theguardian.com
writing
the oceans and humans need sharks. discuss.
true / false

1. the article says ocean acidification will kill all species of shark. t / f
2. ocean acidification is causing tooth decay in sharks. t / f
3. sharks swim with their mouths open primarily to eat plankton. t / f
4. the teeth of ocean predators are not damaged by acidic sea water. t / f
5. researchers studied the teeth of sharks that lived off the german coast. t / f
6. teeth that were put in more acidic salt water resulted in visible damage. t / f
7. ocean acidification could affect how and what sharks eat in the future. t / f
8. the article says ocean acidification could set off a butterfly - wings effect. t / f

synonym match
(the words in bold are from the news article.)

1. crisis

a. decline

1. decay

b. set off

1. ventilate

c. open to attack

1. constant

d. noticeable

1. vulnerable

e. emergency

1. current

f. affect

1. visible

g. non - stop

1. deterioration

h. present

1. impact

i. rot

1. trigger

j. air

Explanation:

1. El artículo dice que la acidificación oceánica es un peligro para los dientes de los tiburones, no que matará a todas las especies de tiburón.
2. Según el artículo, la acidificación oceánica está causando la decaimiento de los dientes de los tiburones.
3. El artículo no menciona que los tiburones nadan con la boca abierta principalmente para comer plancton.
4. El artículo dice que los dientes de los tiburones, que son depredadores oceánicos, sufren daño en aguas ácidas.
5. Los investigadores estudiaron los dientes de tiburones en un acuario en Alemania, no tiburones que viven frente a la costa alemana.
6. El estudio mostró que los dientes en agua de sal más ácida presentaron daño visible.
7. El artículo sugiere que la acidificación oceánica podría afectar la alimentación de los tiburones en el futuro.
8. El artículo menciona efectos en cascada ("domino effects") en los ecosistemas marinos, no un efecto mariposa.

Para el emparejamiento de sinónimos:

1. crisis - e. emergencia
2. decay - i. rot
3. ventilate - j. air
4. constant - g. non - stop
5. vulnerable - c. open to attack
6. current - h. present
7. visible - d. noticeable
8. deterioration - a. decline
9. impact - f. affect
10. trigger - b. set off

Answer:

True / False:

1. F
2. T
3. F
4. F
5. F
6. T
7. T
8. F

Synonym Match:

1. e
2. i
3. j
4. g
5. c
6. h
7. d
8. a
9. f
10. b