Vertebrate Fertilization and Reproductive Strategies

Flashcards covering key concepts related to vertebrate fertilization, reproductive strategies, and related physiological processes.

External Fertilization

A process where eggs and sperm are released into the water to allow for the union of free gametes, common in bony fish and some amphibians.

Internal Fertilization

A reproductive process where sperm are introduced into the female reproductive tract, seen in cartilaginous fishes, some amphibians, and all amniotes.

Oviparity

Developmental strategy where eggs are laid on land or in water.

Ovoviviparity

Strategy where fertilized eggs are kept within the mother until they are ready to hatch, with young obtaining food from egg yolk.

Viviparity

Development strategy where young develop within the mother and obtain nourishment from her blood.

Parthenogenesis

Reproductive strategy where females give birth without male fertilization, resulting in viable, 'normal' offspring.

Environmental Sex Determination

A mechanism where environmental factors like temperature influence the sex of offspring, seen in many fish and reptiles.

Estrus

The period during which females are sexually receptive to males, typically coinciding with ovulation.

Altricial Offspring

Offspring that are underdeveloped at birth or hatching and require long-term parental care.

Precocial Offspring

Offspring that are relatively well-developed at birth or hatching and require less parental care.

Seminiferous Tubules

Structures in the male reproductive system where sperm production occurs.

Corpus Luteum

A temporary endocrine structure involved in ovulation and early pregnancy that secretes hormones such as estrogen and progesterone.

Human Chorionic Gonadotropin (hCG)

Hormone produced by the embryo that maintains the corpus luteum during early pregnancy.

Oxytocin

Hormone that stimulates uterine contractions during childbirth and milk ejection during lactation.

Prolactin

Hormone that controls milk secretion in mammals.