Unit 1 Vocabulary: Anatomy, Endocrine System, and Animal Reproduction

Practice vocabulary flashcards covering terms from Chapters 38, 42, and 49.

Anatomy

The study of the physical structure of organisms and their internal components.

Physiology

The study of the biological functions and processes of living organisms and their parts.

Homeostasis

The physiological state in which physical and chemical aspects of the internal environment are maintained within suitable ranges.

Negative feedback

A homeostatic control mechanism in which a change in a variable triggers a response that counteracts the initial stimulus.

Positive feedback

A control mechanism in which a stimulus amplifies or intensifies the change in the same direction.

Acclimatization

Physiological adjustment by an organism to changes in its natural environment.

Acclimation

Physiological adjustment by an organism to environmental changes under controlled laboratory conditions.

Epithelial tissue

A body tissue composed of tightly packed cells that lines surfaces, cavities, and forms glands.

Chondrocyte

A specialized cell responsible for producing and maintaining the matrix of cartilage.

Osteocyte

A mature bone cell involved in maintaining the structural matrix of bone.

Osteoblast

A cell that synthesizes and deposits new bone matrix.

Osteoclast

A cell that breaks down and resorbs bone tissue.

Intercalated disk

A specialized junctional structure connecting adjacent cardiac muscle cells that facilitates rapid electrical signal transmission.

Classic endocrine signaling

Signaling where hormones are secreted by endocrine glands into the blood to act on distant target cells.

Neuroendocrine signaling

Signaling in which neurosecretory neurons release neurohormones into the bloodstream.

Paracrine regulation

A local signaling mechanism in which secreted molecules act on nearby adjacent target cells.

Autocrine regulation

A local signaling mechanism in which a secreted molecule acts on receptors on the same cell that secreted it.

Prolactin (PRL)

An anterior pituitary hormone that stimulates milk production in mammals.

Growth hormone (GH)

An anterior pituitary hormone that stimulates growth and cell reproduction.

Antidiuretic hormone (ADH)

A posterior pituitary hormone that increases water reabsorption in the kidneys.

Oxytocin

A posterior pituitary hormone that triggers uterine contractions during labor and milk ejection during nursing.

Calcitonin

A hormone produced by the thyroid gland that lowers blood calcium levels.

Parathyroid hormone (PTH)

A hormone produced by the parathyroid glands that increases blood calcium levels.

Epinephrine

A catecholamine hormone released by the adrenal medulla during stress or fight-or-flight responses.

Melatonin

A hormone secreted by the pineal gland that helps regulate circadian rhythms and sleep cycles.

Prothoracicotropic hormone (PTTH)

An insect hormone that stimulates the prothoracic gland to secrete ecdysone.

Ecdysone

A steroid hormone in insects that promotes molting and metamorphosis.

Juvenile hormone (JH)

An insect hormone that retains larval characteristics and prevents metamorphosis during early development.

Parthenogenesis

A form of asexual reproduction in which an egg develops into an embryo without fertilization.

Fast block to polyspermy

A rapid electrical depolarization of the egg plasma membrane following sperm entry to prevent fertilizations by multiple sperm.

Slow block to polyspermy

A long-lasting membrane change produced by the cortical reaction that establishes a hard fertilization envelope.

Oviparous

Refers to animals that lay eggs that develop and hatch outside the mother's body.

Viviparous

Refers to animals in which embryos develop within the mother's body and receive nourishment directly from maternal blood.

Ovoviviparous

Refers to animals that retain fertilized eggs inside the body until hatching, with embryos nourished entirely by egg yolk.

Corpus luteum

A temporary endocrine structure formed from the ruptured follicle after ovulation that secretes progesterone.

Sertoli cells

Supportive cells in the seminiferous tubules that nourish and protect developing germ cells during spermatogenesis.

Leydig cells

Interstitial cells in the testes that secrete testosterone and other androgens.

Human chorionic gonadotropin (hCG)

A hormone secreted by the early embryo that preserves the corpus luteum to maintain progesterone production during early pregnancy.