Bio Exam 3

A reproductive strategy when they produce many offspring in a short amount of time. Most usually don't survive to adulthood. Advantages: they don't have to give as much attention to each child, and even with many deaths there are enough survivors to maintain the population.

A reproductive strategy to not produce as many offspring, and invest a lot of time/resources into each offspring. This means they don't have to produce as many, but they take longer to reach sexual maturity.

They are dioecious and reproduce either sexually or parthogenetically, depending on environmental conditions. Females produce haploid eggs. If they aren't fertilized, they hatch into haploid males, which provide sperm for other haploid eggs. These develop into 2 diploid eggs, which remain dormant through the winter until suitable conditions return, and a female hatches.

Meiotic parthenogenesis is when a haploid ovum is formed, and it may or may not be activated by a sperm. This occurs within honeybees too (workers, queen bee, etc.)

Parthogenesis is the development of an embryo from an unfertilized egg. There are two types: ameiotic, in which no meiosis occurs and the egg is formed my mitotic division; and meiotic, in which meiosis occurs.

Snails: a calcareous structure found on the upper part of the foot. It makes sure the snail doesn't dry out, and protects the snail body from predators when it's retracted.Fish: Gill cover that helps the fish get oxygen: they open as the mouth closes, causing pressure in the fish to drop and the water to flow across the gills (found in classes Actinopterygii, Sarcopterygii, and subclass Holocephali)

They are the only gastropods that can breathe air because they have a pallial lung instead of gills. Their lungs fill with air by contraction of the mantle floor.

Color is the different frequencies or wavelengths of light being reflected. It helps distinguish between male and female, provide protection from environmental difficulty (sunburns), camouflage, prey confusion, and communication (like when an octopus is mad).

They have a notochord, dorsal tubular nerve cord, pharyngeal pouches and slits, endostyle or thyroid, and postanal tail

Most bivalves like mussels are filter feeders, meaning they use their gills to capture phytoplankton and other small particles in the water. Water is drawn into the shell from the posterior ventral surface, passes up through the gills, and doubles back to be expelled right above where it entered. The cilia on the gills are covered in mucus to catch food.

Bivalves have posterior and anterior muscles which are extremely strong, and connect the two valves and contract to close the shell. They oppose the ligament which pulls the valve apart.

The siphuncle is a cord of tissue running through the shell, connecting all chambers of the body. It's used to empty water from the new chambers as the shell grows, which reduces the density of the shell, making the shell act like a floatation device (like the swim bladder in bony fish).

Chromatophores are cells in the skin that contain pigment granules. They are used to change color when the muscle contracts, which is used as danger signals, protective coloring, in courtships rituals, etc. They can display different patterns (messages) on different parts of their body, meaning they can give simultaneous messages at once. This is the most efficient method of communication in any invertebrate.

The statocyst is a fluid-filled sense organ of equilibrium. It contains granules that are used to detect the direction of gravity.

Ammonites are an extinct group of marine invertebrates. They were in the Phylum Mollusca, Class Cephalopoda.