Quiz 4

Question 1

The part of the sea floor that lies between high tide and low tide is called the ______ _____

Answer 1

intertidal zone

Question 2

Describe intertidal zones

Answer 2

• Extreme environment; floods and dries out frequently

- The best understood

Question 3

Describe rocky intertidal zones

Answer 3

• Found in areas with steep coastlines
• Occur in areas that have recently uplifted coastlines
• Limestone is common
• Epifaunal communities are present that attach to the surface of the rocks and cause bioturbation

Question 4

What are the challenges for organisms living in rocky intertidal zones?

Answer 4

1) Water loss, which is overcome by:
- Mobility
- Having protective covering
2) Temperature changes, which is overcome by:
- Mobility
- Shell color adaptations
3) Wave shock, which is overcome by:
- Attaching strongly to the surface; holdfasts

Question 5

Describe byssal threads in domingo mussles

Answer 5

Byssal glands secretes a fluid, the fluid hardens to form byssal threads, and the mussel is now attached to a rock. The mussel can detach from the rock by secreting enzymes

Question 6

What are some adaptations for rocky intertidal zones?

Answer 6

1) Byssal threads

2) Suction cups (clingfishes and gobies)

Question 7

Describe the general characteristics of the organisms that live in the intertidal zone

Answer 7

• Low profile
• Flexible body
• Grow in dense groups

Question 8

What is the primary limiting factor of the intertidal zone?

Answer 8

Competition for space; the fastest moving or growing organisms win

Question 9

Describe the vertical tide zones

Answer 9

• High tide zone: spends most of the time above water
• Mid tide zone: spends about half the time underwater and half the time above water
• Low tide zone: spends most of the time under water

Question 10

Describe the low tide zone

Answer 10

-Fish, sea anemones, sea urchins, seaweeds, and sponges

Question 11

Describe the mid tide zone

Answer 11

• Exposed half of the time and flooded half of the time
• Barnacles, chitons, and mussels
• Too harsh of an environment for species like anemones

Question 12

Describe the high tide zone

Answer 12

• Exposed most of the time

- Lichens and snails

Question 13

Describe feeding in the sandy intertidal

Answer 13

• Detritus is the main food source
• Organisms are either:
  1) Deposit feeders: eat detritus in sediment
  2) Suspension feeders: feed on particles suspended in the water

Question 14

Describe lug worms

Answer 14

They have special hemoglobins that can transport minutes of oxygen

Question 15

Describe mangrove forests

Answer 15

• Generally only occur in subtropics and tropics
• In protected coasts
• Trees and shrubs are facultative halophytes, which means they can tolerate salty environments and anaerobic soil conditions.
• Typically live in or near water

Question 16

List and describe the 4 species of mangrove tree from closest to the ocean to furthest

Answer 16

• Red mangroves: most common, in the daily low tide zone, vivipary, prop roots, salt excluder
• Black mangroves: in daily high tide zone, has roots that grow upwards called pneumataphors, salt excreter.
• White mangroves: not flooded as often, salt excreter
• Buttonwood: not flooded as often

Question 17

Define vivipary

Answer 17

When a plant’s embryo remains attached until it’s dropped

Question 18

Food webs in mangrove environments are primarily ______

Answer 18

Detrital

Question 19

Describe salinity adaptations of mangroves

Answer 19

Salt excluders= roots filter out 99% of the salt (red mangrove)
Salt excreters: release salt from the leaves (black and white mangroves)

Question 20

List the 4 primary functions of mangroves

Answer 20

1) Rotting leaves provide organic matter
2) Roots control erosion
3) Prop roots provide habitats for juveniles and substrate for critters
4) Form rich, densely packed sediment

Question 21

True or false: Mangroves are nurseries for fishes like barracuda

Answer 21

True

Question 22

In the 200-plus years since the industrial revolution began, the concentration of carbon dioxide (CO2) in the atmosphere has increased due to human actions. During this time, the pH of surface ocean waters has fallen by ___ pH units, which is a _____% increase in acidity.

Answer 22

0.1; 30%

Question 23

The ocean absorbs about _____ of the carbon dioxide (CO2) that is released in the atmosphere.

Answer 23

30%

Question 24

The ocean’s average pH is now around ____, which is basic (or alkaline), but as the ocean continues to absorb more CO2, the pH decreases and the ocean becomes more acidic.

Answer 24

8.1

Question 25

What organisms are especially impacted by ocean acidification?

Answer 25

Organisms like oysters and corals that make hard shells and skeletons by combining calcium and carbonate from seawater

Question 26

The pteropod’s shells will eventually ______ if we continue to let the ocean waters get more acidic

Answer 26

dissolve

Question 27

Researchers have already discovered severe levels of pteropod shell dissolution in the _____ Ocean

Answer 27

Southern Ocean

Question 28

The ability of some fish, like _____, to detect predators is decreased in more acidic waters.

Answer 28

clownfish

Question 29

While some species will be harmed by ocean acidification, ____ and _________ may benefit from higher CO2 conditions in the ocean

Answer 29

algae and seagrasses

Question 30

Estimates of future carbon dioxide levels, based on business-as-usual emission scenarios, indicate that by the end of this century the surface waters of the ocean could have a pH around 7.8. The last time the ocean pH was this low was during the middle _______, 14-17 million years ago

Answer 30

Miocene

Question 31

Increasing ocean heat content is contributing to what 3 main things?

Answer 31

1) Sea level rise
2) Ocean heat waves and coral bleaching
3) Melting of ocean-terminating glaciers and ice sheets around Greenland and Antarctica.

Question 32

True or false: Heat already stored in the ocean will eventually be released

Answer 32

True

Question 33

Averaged over the full depth of the ocean, the 1993–2020 heat-gain rates are ___-___ watts per square meter.

Answer 33

0.58-0.78

Question 34

The main source of ocean heat is _______

Answer 34

sunlight

Question 35

More than ___ percent of the warming that has happened on Earth over the past 50 years has occurred in the ocean

Answer 35

90

Question 36

_______ ions are the building blocks for many species to build their shells

Answer 36

carbonate