Bio 1012 Theme 3

alarm reaction

first stage of the general adaptation syndrome; characterized as the body's immediate physiological reaction to a threatening situation or some other emergency; analogous to the fight-or-flight response

Cortisol

stress hormone released by the adrenal glands when encountering a stressor; helps to provide a boost of energy, thereby preparing the individual to take action

Distress

bad form of stress; usually high in intensity; often leads to exhaustion, fatigue, feeling burned out; associated with erosions in performance and health

Eustress

good form of stress; low to moderate in intensity; associated with positive feelings, as well as optimal health and performance

fight-or-flight response

set of physiological reactions (increases in blood pressure, heart rate, respiration rate, and sweat) that occur when an individual encounters a perceived threat; these reactions are produced by activation of the sympathetic nervous system and the endocrine system

general adaptation syndrome

Hans Selye's three-stage model of the body's physiological reactions to stress and the process of stress adaptation: alarm reaction, stage of resistance, and stage of exhaustion

health psychology

subfield of psychology devoted to studying psychological influences on health, illness, and how people respond when they become ill

hypothalamic-pituitary-adrenal (HPA) axis

set of structures found in both the limbic system (hypothalamus) and the endocrine system (pituitary gland and adrenal glands) that regulate many of the body's physiological reactions to stress through the release of hormones

primary appraisal

judgment about the degree of potential harm or threat to well-being that a stressor might entail

secondary appraisal

judgment of options available to cope with a stressor and their potential effectiveness

stage of exhaustion

third stage of the general adaptation syndrome; the body's ability to resist stress becomes depleted; illness, disease, and even death may occur

stage of resistance

second stage of the general adaptation syndrome; the body adapts to a stressor for a period of time

Stress

process whereby an individual perceives and responds to events that one appraises as overwhelming or threatening to one's well-being

Stressors

environmental events that may be judged as threatening or demanding; stimuli that initiate the stress process

autonomic nervous system

controls our internal organs and glands

central nervous system (CNS)

brain and spinal cord

fight or flight response

activation of the sympathetic division of the autonomic nervous system, allowing access to energy reserves and heightened sensory capacity so that we might fight off a given threat or run away to safety

Homeostasis

state of equilibrium—biological conditions, such as body temperature, are maintained at optimal levels

parasympathetic nervous system

associated with routine, day-to-day operations of the body

peripheral nervous system (PNS)

connects the brain and spinal cord to the muscles, organs and senses in the periphery of the body

somatic nervous system

relays sensory and motor information to and from the CNS

sympathetic nervous system

involved in stress-related activities and functions

amino acid

a monomer of a protein

Carbohydrate

a biological macromolecule in which the ratio of carbon to hydrogen to oxygen is 1:2:1; carbohydrates serve as energy sources and structural support in cells

Cellulose

a polysaccharide that makes up the cell walls of plants and provides structural support to the cell

Chitin

a type of carbohydrate that forms the outer skeleton of arthropods, such as insects and crustaceans, and the cell walls of fungi

Denaturation

the loss of shape in a protein as a result of changes in temperature, pH, or exposure to chemicals

deoxyribonucleic acid (DNA)

a double-stranded polymer of nucleotides that carries the hereditary information of the cell

Disaccharide

two sugar monomers that are linked together by a peptide bond

Enzyme

a catalyst in a biochemical reaction that is usually a complex or conjugated protein

Fat

a lipid molecule composed of three fatty acids and a glycerol (triglyceride) that typically exists in a solid form at room temperature

Glycogen

a storage carbohydrate in animals

Hormone

a chemical signaling molecule, usually a protein or steroid, secreted by an endocrine gland or group of endocrine cells; acts to control or regulate specific physiological processes

Lipids

a class of macromolecules that are nonpolar and insoluble in water

Macromolecule

a large molecule, often formed by polymerization of smaller monomers

Monosaccharide

a single unit or monomer of carbohydrates

nucleic acid

a biological macromolecule that carries the genetic information of a cell and carries instructions for the functioning of the cell

Nucleotide

a monomer of nucleic acids; contains a pentose sugar, a phosphate group, and a nitrogenous base

Oil

an unsaturated fat that is a liquid at room temperature

Phospholipid

a major constituent of the membranes of cells; composed of two fatty acids and a phosphate group attached to the glycerol backbone

Polypeptide

a long chain of amino acids linked by peptide bonds

Polysaccharide

a long chain of monosaccharides; may be branched or unbranched

Protein

a biological macromolecule composed of one or more chains of amino acids

ribonucleic acid (RNA)

a single-stranded polymer of nucleotides that is involved in protein synthesis

saturated fatty acid

a long-chain hydrocarbon with single covalent bonds in the carbon chain; the number of hydrogen atoms attached to the carbon skeleton is maximized

Starch

a storage carbohydrate in plants

Steroid

a type of lipid composed of four fused hydrocarbon rings

Trans-fat

a form of unsaturated fat with the hydrogen atoms neighboring the double bond across from each other rather than on the same side of the double bond

Triglyceride

a fat molecule; consists of three fatty acids linked to a glycerol molecule

unsaturated fatty acid

a long-chain hydrocarbon that has one or more than one double bonds in the hydrocarbon chain

Calorie

amount of heat it takes to raise 1 kg (1000 g) of water by 1 °C

essential nutrient

a nutrient that cannot be synthesized by the body; it must be obtained from food

Minerals

inorganic compounds required by the body to ensure proper function of the body

Vitamins

organic compounds required by the body to perform biochemical reactions like metabolism and bone, cell, and tissue growth

Amylase

an enzyme found in saliva and secreted by the pancreas that converts carbohydrates to maltose

Anus

the exit point of the digestive system for waste material

Bile

a digestive juice produced by the liver; important for digestion of lipids

Bolus

a mass of food resulting from chewing action and wetting by saliva

Colon

the largest portion of the large intestine consisting of the ascending colon, transverse colon, and descending colon

Chyme

a mixture of partially digested food and stomach juices

Esophagus

a tubular organ that connects the mouth to the stomach

Gallbladder

the organ that stores and concentrates bile

large intestine

a digestive system organ that reabsorbs water from undigested material and processes waste matter

Liver

an organ that produces bile for digestion and processes vitamins and lipids

oral cavity

the point of entry of food into the digestive system

Pancreas

a gland that secretes digestive juices

Pepsin

an enzyme found in the stomach whose main role is protein digestion

Peristalsis

wave-like movements of muscle tissue

Rectum

the area of the body where feces is stored until elimination

salivary gland

one of three pairs of exocrine glands in the mammalian mouth that secretes saliva, a mix of watery mucus and enzymes

small intestine

the organ where digestion of protein, fats, and carbohydrates is completed

Stomach

a saclike organ containing acidic digestive juices

ATP

adenosine triphosphate, the cell's energy currency

phosphoanhydride bond

bond that connects phosphates in an ATP molecule

Anabolic

(also, anabolism) pathways that require an input of energy to synthesize complex molecules from simpler ones

Bioenergetics

study of energy flowing through living systems

Catabolic

(also, catabolism) pathways in which complex molecules are broken down into simpler ones

Metabolism

all the chemical reactions that take place inside cells, including anabolism and catabolism

active site

enzyme's specific region to which the substrate binds

Coenzyme

small organic molecule, such as a vitamin or its derivative, which is required to enhance an enzyme's activity

Cofactor

inorganic ion, such as iron and magnesium ions, required for optimal enzyme activity regulation

Denature

process that changes a substance's natural properties

induced fit

dynamic fit between the enzyme and its substrate, in which both components modify their structures to allow for ideal binding

Substrate

molecule on which the enzyme acts

appendicular skeleton

the skeleton composed of the bones of the upper limbs, which function to grasp and manipulate objects, and the lower limbs, which permit locomotion

auditory ossicles

(also, middle ear bones) the bones that transduce sounds from the air into vibrations in the fluid-filled cochlea

axial skeleton

skeleton that forms the central axis of the body and includes the bones of the skull, the ossicles of the middle ear, the hyoid bone of the throat, the vertebral column, and the thoracic cage (ribcage)

cardiac muscle tissue

the muscle tissue found only in the heart; cardiac contractions pump blood throughout the body and maintain blood pressure

cartilaginous joint

a joint in which the bones are connected by cartilage

fibrous joint

a joint held together by fibrous connective tissue

hyoid bone

the bone that lies below the mandible in the front of the neck

Joint

the point at which two or more bones meet

Myofibril

the long cylindrical structures that lie parallel to the muscle fiber

Myofilament

the small structures that make up myofibrils

pectoral girdle

the bones that transmit the force generated by the upper limbs to the axial skeleton

pelvic girdle

the bones that transmit the force generated by the lower limbs to the axial skeleton

Sarcolemma

the plasma membrane of a skeletal muscle fiber

Sarcomere

the functional unit of skeletal muscle

skeletal muscle tissue

forms skeletal muscles, which attach to bones and control locomotion and any movement that can be consciously controlled

Skull

the bone that supports the structures of the face and protects the brain