fundamentals Flashcards
(223 cards)
1
Q
What is El Niño?
.
A
A: A warming of the ocean surface in the central and eastern tropical Pacific Ocean
2
Q
What is La Niña?
A
A: A cooling of the ocean surface in the central and eastern tropical Pacific Ocean.
3
Q
Q: What is the North Atlantic Oscillation (NAO)?
A
A: An index describing changes in atmospheric pressure between Iceland and the Azores.
4
Q
Q: How does a positive NAO index affect Northern Europe?
A
A: It brings warmer conditions to Northern Europe.
5
Q
Q: What is a regime shift?
A
A: A long-lasting change in ecosystem structure and function.
6
Q
Q: What caused the regime shift in the North Sea?
A
A: Overfishing and ocean warming.
7
Q
Q: What happened to California sea lions during El Niño events?
A
A: Populations declined due to warmer waters and reduced prey availability.
8
Q
Q: What major event affected emperor penguins in 2022?
A
A: Record-low Antarctic sea ice led to widespread breeding failure.
9
Q
Q: What are top predators vulnerable to in changing ocean climates?
A
A: Habitat shifts, prey loss, and altered breeding conditions.
10
Q
where do mangroves geographically occur
A
sheltered subtropical areas -Caribbean
-indo pacific
11
Q
what conditions do mangroves grow in
A
waterlogged soil
-saline environments down to 10
-the muddy sediment of rivers, estuary’s and deltas
12
Q
What organism group do zooxanthellae belong to?
A
Dinoflagellates (specifically Symbiodinium spp.)
13
Q
What kind of symbiosis exists between corals and zooxanthellae?
A
Mutualism
14
Q
What byproduct of coral respiration do zooxanthellae use?
A
CO₂ (carbon dioxide)
15
Q
What do zooxanthellae provide corals with in return?
A
Oxygen, glucose, glycerol, and amino acids
16
Q
What happens to corals when they expel zooxanthellae?
A
Coral bleaching
17
Q
What is the global percentage of marine species estimated to rely on coral reefs?
A
over 25%
18
Q
What is the typical salinity range suitable for coral reefs?
A
32–42 PSU (practical salinity units)
19
Q
What happens if coral reefs are exposed to low salinity for extended periods?
A
Stress or death
20
Q
hat depth range do most coral reefs grow in?
A
Less than 50 meters
21
Q
Why don’t coral reefs grow well in deep water?
A
Insufficient sunlight for photosynthesis
22
Q
Name two coral reef fish species important for reef health.
A
Parrotfish and surgeonfish
23
Q
What ocean phenomenon can cause mass coral bleaching events?
A
→ El Niño
24
Q
What kind of coral reproduction produces genetically identical offspring?
A
→ Asexual reproduction (budding)
25
What type of coral reproduction increases genetic diversity?
→ Sexual reproduction
26
at environmental cues often trigger coral spawning?
Temperature, moon phases, and daylight hours
27
What marine creature can erode coral skeletons?
→ Sea urchins and boring sponges
28
What kind of reef runs parallel to shore and is separated by a lagoon?
→ Barrier reef
29
What reef type forms around volcanic islands and later encloses lagoons?
Atoll
30
What is the largest coral reef system in the world?
→ Great Barrier Reef
31
What ocean region is warming faster than others?
Arctic Ocean
32
hat are the small units in coral colonies that house individual polyps called?
Corallites
33
Which phylum do reef-building corals belong to?
Cnidaria
34
What class within Cnidaria do reef-building corals belong to?
Anthozoa
35
What kind of coral anatomy includes a mouth, tentacles, and a blind gut?
Coral polyps
36
What is mesoglea in coral anatomy?
A gelatinous non-cellular material between tissue layers
37
Which part of the skeleton houses an individual coral polyp?
The calyx
38
what is the range of psu(practical salinity units) that sea grasses are found in
5-60 psu
39
wat are the physical components of seagrass
leaves
flower
rhizome
roots
40
what the physical components of seaweeds (algae)
holdfast
stripe
blade
41
what does the term macroalgae stand for
seaweeds
42
what does the term microalgae stand for
phytoplankton
43
what are the three major groups of algae
Red algae (Rhodophyceae) Brown algae
(Phaeophyceae)
Green algae (Chlorophyceae)
44
macrophytobenthos (seaweeds) are often found where
rocky substrates
45
microphytobenthos are primarily found as
algal mats (diatoms) on soft sediment
46
what are some abiotic factors affecting seaweed zonation and abundance
* Substratum
* Light
* Nutrients
* Desiccation
* Temperature
* Wave / current action
* Ice scouring
* Acidity
47
name the three members of the Elasmobranchs
sharks skates and rays
48
what buoyancy technique do the elasmobranchs use
fatty liver
49
what type of scales do the elasmobranchs have
placoid
50
what are some reproductive adaptations of elasmobranchs
fewer
larger
self-sufficient young
51
what class do squid belong to
Cephalopoda
52
what feature allows squid to preform jet propulsion
siphon and muscular mantle
53
what is the primary mode of locomotion in squid
jet prolusion and fin undulation
54
what type of muscle is involved in jet propulsion
circular and radial mantle muscles
55
how do squid control chromophore's
the Optic lobe
56
what are chromophores
pigment containing cells controlled by muscles for colour change
57
what functions does color change in squid serve
mating, camouflage, communication, threat displays
58
what type ferritization do squid use
internal
59
what structure do male squid often use to transfer the spermatophore
a hectocotylus
60
what is a spermatophore
a capsule of sperm transferred by the male to the female
61
how to squid larvae develop
directly no larval stage
62
what type of Reproductive stratagey is common in squid
Semelparity—single reproductive event followed by death.
63
what are some features that allow squid to e efficient hunters
Tentacles with suckers/hooks, beak, high-speed jet propulsion, and good eyesight.
64
How do squid avoid predation
camouflage, ink ejection, fast swimming veil vertical migration
65
what is veil vertical migration
moving up and down the water column to avoid predation
66
What is the role of the statocyst in squid?
Balance and orientation—functions like a vestibular system.
67
What are giant axons used for in squid?
Rapid conduction of nerve impulses for fast jetting escape.
68
What is the primary difference between red and white muscle in fish, and how does this affect their swimming behavior
Red muscle supports sustained swimming; white muscle is for short bursts of speed.
69
How does the swim bladder contribute to buoyancy control in bony fish?
It allows fish to regulate their position in the water column without expending energy.
70
Why don’t sharks have swim bladders, and how do they maintain buoyancy
They rely on large oily livers and dynamic lift from pectoral fins.
71
What is countershading in fish and why is it an effective camouflage strategy?
Dark top, light bottom—helps blend with both the ocean surface and depths.
72
What is the lateral line system and what function does it serve
A sensory organ that detects water movement and vibrations.
73
How do electroreception capabilities benefit species like sharks and rays
They help detect prey through electric fields, even if buried under sediment.
74
What advantages does internal fertilization provide for some fish species?
Increases chances of fertilization in open water or complex habitats.
75
What are the main types of fish scales and how do they differ?
Placoid (sharks), cycloid & ctenoid (bony fish)—vary in structure and growth.
76
Why are fish gills so efficient at extracting oxygen from water?
Large surface area, counter-current exchange system maximizes O₂ absorption
77
What is the operculum and what role does it play in fish respiration?
Bony flap that protects gills and aids water flow over them.
78
What role do myomeres play in fish locomotion?
W-shaped muscle blocks that contract in sequence for efficient swimming.
79
How do bottom-dwelling fish like flounders adapt morphologically to their lifestyle
Flattened bodies, eyes migrate to one side, camouflaged coloration.
80
Compare the diets and jaw structures of herbivorous vs carnivorous fish
Herbivores: flat teeth, long guts. Carnivores: sharp teeth, shorter intestines.
81
How do fish use schooling as a defense mechanism?
Confuses predators, increases survival by safety in numbers
82
What is ram ventilation and which fish use it?
Constant swimming forces water over gills—used by tuna and some sharks.
83
Why is the forked tail shape common in fast-swimming fish?
Reduces drag, increases speed and efficiency.
84
How does a fish’s fin configuration relate to its mode of swimming?
Different fin shapes support stability, maneuverability, or speed.
85
What environmental challenges do deep-sea fish face, and how are they adapted?
High pressure, low light—bioluminescence, soft bodies, enhanced senses.
86
How does ontogenetic shift apply to fish diets and habitat use?
fish change diet and habitat as they grow to reduce competition.
87
What role do fish play in marine food webs?
Both predator and prey—link lower trophic levels to apex predators.
88
How can overfishing disrupt fish reproductive success?
Removes large, fertile individuals—lowers population regeneration.
89
Why are migratory fish particularly vulnerable to habitat degradation?
They rely on multiple habitats during life stages—fragmentation disrupts cycles
90
What is diel vertical migration, and do any fish do it?
Daily movement up/down water column—some mesopelagic fish do this to feed.
91
How does mouth position in fish relate to feeding strategy?
Superior (surface feeders), terminal (active chasers), inferior (bottom feeders).
92
Why is biodiversity among fish species important for ecosystem health?
Maintains food web balance, resilience to environmental changes.
93
what is fusiform
streamlined
94
what is depressiform
flattened top-to-bottom
95
what is compressiform
flattened side-to-side
96
what is anguilliform
elongated
97
what is globiform
round
98
Which body form is typical of fast, open-water fish like tuna and mackerel?
Fusiform—streamlined for speed and endurance in open water.
99
What is a compressiform body shape and what advantage does it provide?
Laterally flattened; improves maneuverability in coral reefs or kelp forests.
100
Describe the depressiform body form and give an example of a fish with this shape.
Flattened dorsoventrally (top-down); common in bottom-dwellers like rays and flounders.
101
What are anguilliform fish and how does their shape benefit them?
Elongated, snake-like (e.g., eels); good for hiding in crevices and burrowing.
102
Which body form is common in slow-swimming or sedentary fish like pufferfish?
Globiform—round body provides protection, often combined with spines or toxins.
103
why do flatfish like plaice have eyes on one side of their body
It's an adaptation to living on the sea floor, it improves Vision while camouflaged
104
How do pectoral fin positions differ between bottom dwelling and pelagic fish
Bottom dwellers have low wide fins for support Whereas pelagic fish have fins for lift and control
105
what fin shape is associated with rapid busts of speed
Lunate or fork tailed
106
what fin shape is assorted with mauver ability and sharp turn's
Rounded or truncate tails—less speed, more control.
107
How does the body shape of a reef fish support survival in complex habitats?
Compressiform shapes allow quick turns and navigation through tight spaces.
108
Why do many deep-sea fish have soft, flabby bodies and large mouths
Saves energy in low-food environments; large mouths help catch rare prey
109
How is the shape of a shark’s body different from that of a bony fish?
Sharks are fusiform but stiffer with heterocercal tails; bony fish often have symmetrical tails.
110
What is a heterocercal tail and which group of fish typically has it?
Unequal tail lobes—top lobe longer; seen in sharks, helps with lift.
111
How does body form influence a fish’s position in the water column?
Streamlined forms are pelagic; flattened or elongated forms suit benthic life.
112
What is the function of finlets in fish like tuna?
Small stabilizers that reduce turbulence and improve efficiency at high speeds.
113
Why are eels well adapted for narrow crevices or burrowing?
Their anguilliform shape allows flexibility and access to tight spaces.
114
How does a fish’s morphology reflect its ecological niche?
Shape, fin placement, and mouth position align with feeding, movement, and habitat use.
115
What trade-off do fish with high maneuverability often make?
Reduced speed—rounded fins and flattened bodies increase drag but improve control.
116
How can coloration and body form work together in predator avoidance?
Camouflage (countershading or mimicry) + body form allows hiding or rapid escape.
117
What structural adaptation allows sharks to maintain buoyancy without a swim bladder?
Sharks have large, oil-rich livers that reduce their overall density and aid buoyancy, as well as dynamic lift from pectoral fins and their heterocercal tail.
118
How do ampullae of Lorenzini help sharks detect prey?
These electroreceptors detect the electrical fields generated by muscle activity in prey, allowing sharks to hunt even in murky water or under sand.
119
What are dermal denticles and their function in shark locomotion?
: Dermal denticles are small, tooth-like scales that reduce water turbulence and drag, increasing swimming efficiency and stealth.
120
How does the lateral line system aid sharks?
It detects vibrations and water movements, helping to locate prey, avoid predators, and navigate in low visibility.
121
What are vibrissae and how do they function in seals?
Vibrissae are sensitive whiskers used to detect water movement and locate prey, especially useful in dark or murky environments.
122
How does blubber benefit seals?
Blubber provides thermal insulation in cold waters, stores energy, and aids in buoyancy.
123
What adaptations help seals move in water versus land?
Streamlined bodies and flipper-like limbs aid swimming. On land, true seals (Phocidae) move by wriggling, while sea lions (Otariidae) can walk on flippers.
124
: What is delayed implantation in seals?
It’s a reproductive strategy where the fertilized egg doesn’t implant immediately, allowing birth to occur during optimal conditions.
125
How do seals dive for long periods without breathing?
Seals reduce heart rate (bradycardia), redirect blood to essential organs, and store oxygen in muscles using myoglobin.
126
where does the term Pelagic refer to
the mid water column
127
where does the term demersal refer to
near bottom
128
where does the term benthos refer to
the bottom
129
Where:
𝑊
W = weight in kilograms
𝐿
L = fork length in centimetres
What is the predicted weight of a yellowfin tuna with a fork length of 90 cm?
14.22 kg
130
Which one of the following is used to increase buoyancy in some deep-sea squid?
Fat deposits around internal organs
Variable-volume gas bladder
Replacement of sodium ions
Oil sac in mantle cavity
Replacement of sodium ions
131
list in order going down the ocean depth zones
epipelagic-200
mesopelagic-1000
bathypelagic-3000
abyssopelagic -6000
hadal- 6000+
132
Open ocean salinity is typical around
35
133
as the ocean floor lowers from land describe in order of geographic structures
continental shelf
continental slope
continental rise
abyssal plain
134
What are the three main vertical layers of the ocean?
The surface mixed layer, the thermocline (or pycnocline), and the deep ocean.
135
What characterizes the surface mixed layer?
It has relatively uniform temperature and salinity due to wind mixing and surface heating
136
What is the typical depth range of the Surface mixed Layer?
0-100m can change despearely on time of year
137
What defines the thermocline?
A zone of rapid temperature change with depth, typically found below the mixed layer.
138
What is the halocline?
A layer where salinity changes rapidly with depth.
139
What is the pycnocline?
A layer of rapidly increasing density with depth, influenced by both temperature and salinity.
140
Where is the pycnocline typically found?
Between approximately 100–1000 meters depth.
141
What defines the deep ocean layer?
Cold, dense water with relatively stable temperature and salinity, below the thermocline.
142
Why is vertical mixing between layers limited
Because of stable stratification—denser water lies beneath less dense water, resisting mixing.
143
How does the mixed layer depth change seasonally?
It deepens in winter due to cooling and wind-driven mixing, and shallows in summer due to surface warming.
144
Which ocean layer contains the most biomass?
The surface mixed layer, due to availability of light and nutrients.
145
Why is the pycnocline important for marine life?
It can limit vertical nutrient transport and isolate biological communities.
146
What is the permanent thermocline?
A persistent layer of rapid temperature change found below the seasonal thermocline in most ocean regions.
147
What is a seasonal thermocline?
A temporary thermocline that forms during summer in temperate regions and disappears in winter.
148
What is the role of the thermocline in heat distribution?
It acts as a barrier that limits heat exchange between the surface and deep ocean.
149
what is The Reynolds number
describes the ratio of inertial forces to viscous forces within a fluid flow.
150
give an example of an adaption a sea bird has
* Salt glands - Extra renal-kidney in the
orbit of the eye – deals with salt (get
fresh water from prey)
* The salt they take in is absorbed and
moves through their blood stream into a
pair of salt glands above their eyes. The
densely salty fluid that results is excreted
from the nostrils and runs down grooves
in the bill.
Oils to keep feathers dry
* In fact, cormorants do have a preen gland,
and although simple in structure, it
functions quite well and serves the same
purpose as it does in other birds. In fact,
most of a cormorant's feathers are
waterproof.
- nk selected
-adapations to dive underwater
-
151
give an example of a surface plunging bird
terns
152
deep plunging
gannetts
153
pursuit plunging
auks
154
stealing in flight
skau
155
dip feeding
long tailed skua
156
surface scavenging
gulls gannets fulmar
157
fluttering on the surface
petrels
158
what are some of the feeding of sea birds
breaks
migrations
159
What are the two main suborders of cetaceans?
Odontocetes (toothed whales) and Mysticetes (baleen whales)
160
What distinguishes odontocetes from mysticetes in terms of feeding?
Odontocetes use teeth and echolocation for hunting, while mysticetes filter feed using baleen plates
161
How do cetaceans communicate underwater?
Through a range of vocalisations, including clicks, whistles, and pulsed calls.
162
What is echolocation and which cetaceans use it?
Echolocation is a sound-based navigation and foraging method used primarily by odontocetes.
163
How is photo-ID used in studying cetaceans?
It tracks individual cetaceans over time to study life history traits like longevity, reproduction, and migration.
164
What seasonal behaviours do cetaceans exhibit?
Breeding, migrating to calving or feeding grounds, and feeding intensively during productive seasons.
165
How do movement patterns of cetaceans vary?
They can be short-term (daily foraging trips) or long-term/seasonal (e.g., annual migrations)
166
What is the purpose of cetacean stranding schemes?
To monitor health, mortality, and environmental stressors affecting marine ecosystems.
167
Why are cetaceans considered ecosystem sentinels?
Because their health and distribution reflect changes in the marine environment.
168
Give an example of a foraging adaptation in cetaceans
Deep diving in sperm whales to hunt squid or bubble-net feeding in humpbacks.
169
what is an example of a mysticetes
blue whale (baleen whale)
170
what is an example of a Odonotcetes
dolphin (toothed whale)
171
name the feeding techniques of a Mysticetes
engulfing
suctioning
skimming
lunging
172
Phocidae refers to the group
true seals
173
Otariidae refers to the group
eared seals
174
Odobenidae refers to the group
walrus
175
Phocidae differentiate into what two groups
northern and southern species
176
otariide differentiate into which groups
fur seals and sea lions
177
What are the two main groups of pinnipeds?
Phocids (true seals) and Otariids (eared seals, including sea lions and fur seals).
178
How do pinnipeds maintain body temperature in cold water?
Through thermoregulation mechanisms like blubber insulation and vascular heat exchange.
179
How is photo-ID useful for studying pinnipeds?
It helps track individual life histories, behavior, reproductive success, and population dynamics.
180
What are the seasonal cycles in pinniped behavior?
Breeding, moulting, and feeding seasons that follow predictable annual patterns.
181
What drives pinniped distribution on land and at sea?
Environmental factors such as prey availability, temperature, and suitable haul-out sites.
182
What types of movement patterns do pinnipeds exhibit?
Short-term (daily) movements, seasonal migrations, and consistent individual foraging routes.
183
How are seals used as oceanographic surveyors?
They carry data loggers that collect information on temperature, salinity, and depth while diving.
184
What scientific value do seals offer through environmental data collection?
They provide hard-to-reach ocean data, contributing to climate and oceanographic research innovations.
185
Chi-Square Test
Use:
Test relationships between categorical variables.
Example: Testing if voting preference is related to gender.
186
Kruskal-Wallis Test
Use:
Non-parametric version of ANOVA for comparing more than two groups.
Example: Compare stress levels across different occupations.
187
Mann-Whitney U Test
Use:
Non-parametric test to compare differences between two independent groups.
Example: Comparing customer satisfaction scores between two stores.
188
Correlation (Pearson or Spearman)
Use:
Measure the strength and direction of a relationship between two variables.
Example: Correlation between hours studied and exam score.
Pearson: For continuous, normally distributed data.
Spearman: For ranked or non-normally distributed data.
189
ANOVA (Analysis of Variance)
Use:
Compare means among three or more groups.
Example: Testing the effectiveness of multiple diets.
190
Paired t-test
Use:
Compare means from the same group at different times.
Example: Before and after treatment on the same subjects
191
t-test (Student's t-test)
Use:
Compare the means of two groups.
Example: Comparing test scores between two teaching methods.
192
What is an ocean gyre?
A1: An ocean gyre is a large system of circular ocean currents formed by global wind patterns and forces created by Earth’s rotation (Coriolis effect)
193
Name the five major ocean gyres.
A2: North Atlantic, South Atlantic, North Pacific, South Pacific, and Indian Ocean gyres.
194
How does the Coriolis effect influence gyres in each hemisphere?
In the Northern Hemisphere, gyres rotate clockwise; in the Southern Hemisphere, they rotate counterclockwise due to the Coriolis effect.
195
What is the main driver of surface ocean currents?
Wind, particularly the trade winds and westerlies, drives surface ocean currents.
196
What is the role of ocean gyres in climate regulation?
Ocean gyres redistribute heat by moving warm water from the equator toward the poles and cold water toward the equator.
197
What is the Ekman transport and how does it affect gyres?
Ekman transport is the net movement of water at 90° to the wind direction due to the Coriolis effect; it helps create the central water piling that forms gyres.
198
What is geostrophic flow in ocean gyres?
the pressure gradient force from water piling up in the gyre center is balanced by the Coriolis effect, causing circular motion.
199
What is the Great Pacific Garbage Patch and how is it related to gyres?
It is a concentration of marine debris in the North Pacific Gyre caused by circulating currents trapping floating plastics.
200
What is atmospheric circulation?
Atmospheric circulation is the large-scale movement of air that distributes thermal energy across the Earth
201
What are the three main atmospheric circulation cells?
Hadley Cell (0–30°), Ferrel Cell (30–60°), and Polar Cell (60–90°) in each hemisphere.
202
What are the trade winds and where are they found?
Trade winds are easterly winds found in the tropics (0–30°) within the Hadley cell.
203
How does atmospheric circulation influence ocean currents?
Wind belts created by atmospheric circulation push surface water, creating currents and gyres in the ocean.
204
What is upwelling and where does it commonly occur?
Upwelling is the upward movement of deep, cold, nutrient-rich water; it often occurs along coastlines where surface winds push water away.
205
What impact does El Niño have on gyres and atmospheric circulation?
El Niño disrupts normal wind and current patterns, weakening trade winds and altering gyre strength and direction, especially in the Pacific.
206
How do ocean gyres contribute to marine biodiversity?
Gyres influence nutrient distribution and water temperature, affecting the habitat and productivity of marine ecosystems.
207
Why can't macroalgae attach to sandy beach substrata?
Because the sandy substratum is mobile, making it unstable for attachment.
208
What forms the base of the food web on sandy beaches?
Detritus in or on the sediment and plankton/detritus consumed by suspension feeders.
209
What microscopic organisms might be found on the sand surface of beaches?
Benthic diatoms
210
: What feeding strategy is common among animals living in sandy beach environments?
Suspension feeding and deposit feeding on detritus.
211
Why might sandy beaches appear lifeless at first glance?
Because many infaunal invertebrates and fish are hidden beneath the surface.
212
How do infaunal species survive low tide on sandy shores?
By burrowing to stay protected and remain in saltwater.
213
What environmental factor creates gradients along the beach slope?
The cycle of tidal inundation and exposure, along with sediment properties
214
Where are species with specialized adaptations usually found on a sandy beach?
In narrow height ranges, particularly on the upper shore
215
What defines an organism as zooplankton?
Heterotrophic organisms that cannot swim against ocean currents and are passively transported by water masses.
216
Do all zooplankton remain planktonic their whole life?
No. Holoplankton do, but meroplankton only spend part of their life (e.g. larvae or eggs) in the plankton.
217
Give an example of a large zooplankton organism.
Scyphozoan jellyfish or colonial salps
218
Which phyla include zooplanktonic species?
Nearly all phyla with heterotrophic representatives, including Chordata and Cnidaria.
219
What type of environmental conditions do rocky shores present?
Challenging conditions, including wave action, desiccation, and temperature extremes
220
What types of animals are commonly found on rocky shores?
Sessile and semi-sessile fauna with protective shells (e.g., barnacles, limpets, mussels).
221
What types of feeding modes are seen in rocky shore animals?
A variety, including filter feeding, grazing, scavenging, and predation.
222
How does species richness change with proximity to the sea?
Species richness increases as you move closer to the sea.
223
Where on the rocky shore is species richness typically higher?
In wet microhabitats, such as tide pools and crevices.
