Bivalves

Question 1

What phylum and class do they belong to

Answer 1

Mollusca

Bivalvia

Question 2

When did they evolve and are there around today

Answer 2

Cambrian

Yes

Question 3

What dies articulated mean

Answer 3

The valves are joined together but can move along the hinge lines

Question 4

What does disarticulated mean

Answer 4

The valves are no longer joined together

Question 5

What does equivalve mean

Answer 5

Valves of the same size

Question 6

What does inequivalve mean

Answer 6

Valves of different size

Question 7

What are siphons

Answer 7

Soft tissue that take in fresh water and filter it and removed used water

Question 8

Where are most bivalves symmetry

Answer 8

Along the hinge line

Question 9

How do you know if a bivalve is left or right (sinistral or dextral)

Answer 9

The direction of the umbone

Question 10

Where is the umbone

Answer 10

It sits directly above the hinge line

Question 11

What does the hinge itself consist of and rowdies it work

Answer 11

Protruding teeth and sunken pit-like sockets

These articulate against one another when the valves open and close, keeping the structure stable

Question 12

On the outside f the shell, where the valves are joined what is there and what covers the area

Answer 12

Hinge plate

A ligament covers the area but decays in death

Question 13

Where is the shell secreted

Answer 13

Mantle (part of the soft tissue inside the bivalve

Question 14

What marks the position of the soft tissue

Answer 14

Palatial line on the inside of the shell

Question 15

Finding it hard to remember the differences between Bivalves and Brachiopods?

Answer 15

Got to page 245 in the Geology OCR AS/A2 text book

Question 16

What is the byssus

Answer 16

A group of thread-like structures made of a protein called collagen

Question 17

What is a byssal notch

Answer 17

A shallow indentation or hole, which means the byssus does not interfere with opening and closing of the valves

Question 18

What is cement

Answer 18

The calcareous substance secreted by the mantle and attaches the left valve to the substrate

Question 19

What did they use to feed

Answer 19

Inhalant and exhalant siphons

Question 20

What do the inhalant and exhaling siphons do

Answer 20

Inhalant-bring’s in fresh water

Exhalant-remove waste water

Question 21

What removes particles from the water

Answer 21

The gills

Question 22

How do some bivalves move

Answer 22

Using a muscular foot

Question 23

What are the three types of epifaunal bivalves

Answer 23

Mytilus
Ostrea
Gryphaea

Question 24

What is unique about Mytilus that no other type has

Answer 24

It is attached to the substrate by the byssus (allows lying in high-energy environment)

Question 25

What does the layer of periostracum do (Mytilus)

Answer 25

Protects it from acidic rain/river water

Question 26

Function of strong shell (Mytilus)

Answer 26

Lives in a high-energy environment

Question 27

Streamline (Mytilus)

Answer 27

Protect against currents

Question 28

Large adductor muscles (Mytilus)

Answer 28

To hold valves tightly together to stop the shell drying out in low tide

Question 29

What is special about Ostrea

Answer 29

It is cemented

Question 30

How do they attach to the sea floor (Ostrea)

Answer 30

By secreting cement for the mantle

Question 31

What valve always attaches (Ostrea)

Answer 31

Left valve

Question 32

Strong, thick shell (Ostrea)

Answer 32

To withstand high-energy environments

Question 33

Strong adductor muscle (Ostrea)

Answer 33

To keep closed in high-energy currents

Question 34

Vales of different sizes (Ostrea)

Answer 34

Larger left valve is cemented to the rock while right valve acts like a lid

Question 35

What type of oyster is Gryphaea

Answer 35

Extinct

Question 36

How did Gryphaea live

Answer 36

Rested on sea floor on a convex left valve so left valve was much bigger than right valve

Question 37

What effect did this convex left valve give them (Gryphaea)

Answer 37

Snow shoe effect

Question 38

What are the two examples of infaunal bivalves

Answer 38

Crytherea | Solen

Question 39

How deep of a burrower is Crytherea

Answer 39

Shallow

Question 40

What part is shallow (Crytherea)

Answer 40

Palatial sinus, indicating short siphons

Question 41

What do ribs/growth lines show (Crytherea)

Answer 41

Help grip the sediment when burrowing

Question 42

Streamline shell (Crytherea)

Answer 42

To help move through the sand easier

Question 43

Large adductor muscle scars (Crytherea)

Answer 43

For large adductor muscle for keeping vales closed

Question 44

How deep of a browser is Solen

Answer 44

Deep

Question 45

What is the shell (Solen)

Answer 45

Elongated and the valves not completely close

Question 46

What does a large palatial sinus mean (Solen)

Answer 46

Long siphons

Question 47

Unornamented and streamline (Solen)

Answer 47

Enable it to move easily up and down through the sediment

Question 48

Small adductor muscle scars (Solen)

Answer 48

No need to open and close the valves in the burrow

Question 49

Anterior and posterior gapes (Solen)

Answer 49

Indicates that the siphons cannot be retracted into the burrow

Question 50

Name the nektonic bivalve

Answer 50

Pecten

Question 51

What is special about pecten and how does it do it

Answer 51

Swimming | Uses a single powerful adductor muscle called monomyarian

Question 52

How are the valves shaped (Pecten)

Answer 52

The valves are flattened on one side and rounded on the other like an aeroplane

Question 53

Ribbed, corrugated thin valves (Pecten)

Answer 53

Gives it strength without weight

Question 54

One flattered valve and one curved (Pecten)

Answer 54

Gives hydrofoil effect to allow movement through the water when swimming