BIOL 1720 Exam 1 Review

Covers: Animal Form and Function; Hierarchical Organization of Body Plans; Animal Nutrition; Phases of Food Processing; Feeding Mechanisms; The Nervous System; Sensory Systems; Endocrine System

Anatomy

The study of the biological form of an organism.

Physiology

The study of the biological functions an organism performs.

Adaptation

An environmentally advantageous trait.

Homeostasis

Regulation of the internal environment.

Epithelial Tissue

Tissue that covers the outside of the body and lines organs and cavities.

Connective Tissue

Tissue that supports and binds other tissues together.

Muscle Tissue

Tissue composed of thin cells capable of contraction.

Nervous Tissue

Tissue that senses stimuli and transmits signals throughout the body.

Endothermic

Animals that generate heat by metabolism, maintaining a constant internal temperature (eg. birds and mammals)

Ectothermic

Animals that gain heat from external sources, with varying internal temperatures (eg. most invertebrates, fish, amphibians)

Calorie

The energy produced by the oxidation of 1g of material.

Essential Nutrients

Nutrients that must be obtained from the diet because they cannot be synthesized by the body.

Intracellular Digestion

Digestion that occurs inside the cells.

Extracellular Digestion

Digestion that occurs outside of cells, through a digestive system.

Neurotransmitter

Chemical messengers that transmit signals across synapses.

Sensory Receptors

Cells that transduce stimulus energy and transmit signals to the central nervous system.

Hormones

Chemical signals secreted into the circulatory system that communicate with various body systems.

Feedback Loop

A system that uses information from the output of a process to regulate that same process.

Vasodilation

The increase in blood flow to the skin to facilitate heat loss.

Vasoconstriction

The decrease in blood flow to the skin to lower heat loss.

Photoreceptors

Cells that contain light-absorbing pigments to detect light.

Mechanoreceptors

Receptors that sense physical deformation caused by mechanical energy.

Thyroid Hormones

Hormones that regulate metabolism and other functions in the body.

Sodium-Potassium Pump

A transport protein that moves sodium out of cells and potassium into cells.

Gastrointestinal Tract

The digestive system that includes various organs where digestion takes place.

Set Point

The desired value of a physiological parameter that the body tries to maintain.

Action Potential

A rapid change in membrane potential that travels along the axon of a neuron.

Integumentary System

The organ system that includes skin, hair, nails, and glands, providing protection and regulation.

Keratin

A protein that is a key structural material making up the outer layer of human skin, hair, and nails.

Adipose Tissue

A type of connective tissue that stores fat and provides insulation and cushioning.

Digestive Enzymes

Biological molecules that facilitate the breakdown of food into absorbable units.

Synapse

The junction between two neurons where neurotransmitters are released to transmit signals.

Neuroglia

Supporting cells in the nervous system that provide structural and functional support to neurons.

Skin Homeostasis

The skin's role in maintaining the body's temperature and fluid balance.

Depolarization

Small rise in resting potential; sodium enters the cell, causing the cell to become more positive

Hyperpolarization

Small increase in resting potential; sodium enters the cell, causing the cell to become more negative

Genome

Determines animal body plans

Law of Diffusion

Dictates the rate at which materials diffuse into and out of tissue

Apical surface of epithelium

Faces internal or external environment; carries out functions like absorption, secretion, and sensory transduction

Basolateral surface of epithelium

Connects epithelial cells with other epithelial cells

Cuboidal Epithelial Tissue

Epithelial tissue shaped like dice; Secretion and absorption

Columnar Epithelial Tissue

Epithelial tissue shaped like bricks; Secretion, absorption, and movement of substances with cilia

Squamos Epithelial Tissue

Epithelial tissue shaped like floor tiles; primarily for protection

Function of Epithelium

Protection and regulation of materials in and out of the body

Simple (Epithelial Cells)

Single cell layer of epithelial cells

Stratified (Epithelial Cells)

Multiple tiers of epithelial cells

Pseudostratified (Epithelial Cells)

A single layer of epithelial cells of varying lengths

Skeletal Muscle Tissue

Attached to bones, responsible for voluntary movement, and appears striated; made of long, multinucleated cells

Smooth Muscle Tissue

Found in the walls of internal organs like the stomach and bladder, functions involuntarily, and lacks striations; made of small, single nucleated cells

Cardiac Muscle Tissue

Exclusive to the heart, contracts involuntarily to pump blood, and exhibits striations similar to skeletal muscle, but with unique junctions called intercalated discs that allow for coordinated contractions; made of small, multiple nucleated cells

Glial Cells

Help nourish, insulate, and replenish neurons

Regulator

An animal that uses internal mechanisms to control internal change despite external fluctuation

Conformer

An animal that allows its internal condition to change in accordance with external changes

Function of Homeostasis

For a given variable, fluctuations above or below a set point serve as a sensor and trigger a stimulus, which is detected by a motor output (response)

Negative Feedback Loop

Helps to return a variable to a normal range (eg. glucose regulation)

Positive Feedback Loop

Amplifies a stimulus; not usually contribute to homeostasis in animals

Thermoregulation

The process by which animals maintain an internal temperature within a tolerable range

Poikilotherm

Body temperature varies with its environment

Homeotherm

Has a relatively constant body temperature

Insulation

Skin, feathers, fur, or blubber that functions to reduce heat flow between an animal and its environment

Countercurrent Exchange

When organisms transfer heat between fluids flowing in opposite directions to reduce heat loss (eg. dolphins or ducks)

Evaporative Heat Loss

Allows organisms to lose heat through the evaporation of water from their skin; can be done through panting, sweating, or bathing

Thermogenesis

The adjustment of metabolic heat production to maintain body temperature; can be increased by muscle activity such as moving or shivering, or when hormones cause mitochondria to increase their metabolic acitivity

Endocrine System

Secretes hormones that coordinate slower but longer-acting responses (eg. reproduction, development, energy metabolism, growth)

Nervous System

Conveys high-speed electrical signals along neurons; facilitate the regulation of other cells

Local Regulators

Molecules that act over short distances, reaching target cells solely by diffusion

Paracrine Signaling

A type of cell-cell communication in which the target cells lie near the secreting cells

Autocrine Signaling

A type of cell-cell communication where the target cell is also the secreting cell

Pheromones

Chemicals that are released into the environment to allow for interspeciary communication

Endocrine Glands

Ductless organs that contain groups of endocrine cells; secrete hormones directly into surrounding fluid

Lipid-soluble Hormones (Steroid Hormones)

Pass easily through cell membranes; diffuse across cell membranes

Water-soluble Hormones (Polypeptides and Amines)

Do not pass easily through cell membranes; secreted by exocytosis

Prostaglandins

Help regulate aggregation of platelets; promote fever and inflammation and intensify the sensation of pain

Insulin

Antagonistic hormones that decrease blood glucose; promotes fat storage and uptake of glucose

Glucagon

Antagonistic hormones that increase blood glucose; stimulates breakdown of fat and protein into glucose

Hypothalamus

Receives information from the nervous system and initiates responses through the endocrine system

Posterior Pituitary

Stores and secretes hormones that are made in the hypothalamus

Anterior pituitary

Makes and releases hormones under regulation of the hypothalamus

Oxytocin

Released from the posterior pituitary’ regulates milk secretion by the mammary glands

Antidiuretic Hormone (ADH)

Regulates physiology and behavior

Hormone Cascade Pathway

When a hormone stimulates the release of a series of other hormones, the last of which activates a non-endocrine target cell

Growth Hormone (GH)

Secreted by the anterior pituitary gland and has tropic and nontropic actions; promotes growth directly and stimulates production of growth factors

Tropic Hormone

Regulates the function of endocrine cells or glands

Parathyroid Hormone (PTH)

Antagonistic hormone that is released by the parathyroid glands; increases the level of blood calcium

Calcitonin

Antagonistic hormone that is released by the thyroid gland; decreases the level of blood calcium

Adrenal Gland

Consists of two glands, the adrenal medulla and adrenal cortex; facilitates physiological response to stress

Adrenal Medulla

Secretes epinephrine (adrenaline) and norepinephrine (noradrenaline) in response to stress-activated impulses

Glucocorticoids

A type of corticosteroid that influences glucose metabolism and the immune system

Mineralocorticoids

A type of corticosteroid that affects salt and water balance

Testes

Synthesize androgens, mainly testosterone, which stimulate development and maintenance of the male reproductive system

Estrogens

Responsible for maintenance of the female reproductive system and the development of female secondary sex characteristics

Progesterone

Involved in preparing and maintaining the uterus in mammals