bio final Flashcards

The process by which organisms maintain a stable internal environment despite changes in external conditions. This involves feedback mechanisms that regulate body temperature, pH, glucose levels, etc.

A passive process where molecules move from an area of higher concentration to an area of lower concentration. In single-celled organisms, diffusion directly exchanges gases and nutrients with the environment. In multicellular organisms, diffusion occurs across cell membranes and within tissues to distribute oxygen, nutrients, and waste products.

The process by which organisms maintain a stable internal environment despite changes in external conditions.

A passive process where molecules move from an area of higher concentration to an area of lower concentration.

Transmit sensory information from receptors to the central nervous system (CNS).

Carry signals from the CNS to muscles and glands.

Connect sensory and motor neurons within the CNS.

Receive signals from other neurons.

Contains the nucleus and organelles.

Transmits electrical impulses away from the cell body.

Release neurotransmitters to communicate with other neurons.

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

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

Support neurons by providing nutrients, removing waste, and insulating axons with myelin sheaths.

Comprises the brain and spinal cord.

Includes all nerves outside the CNS.

Automatic responses to stimuli that involve sensory neurons, interneurons, and motor neurons.

Specialized cells that detect stimuli and convert them into electrical signals.

Mechanoreceptors in the skin.

Photoreceptors (rods and cones) in the retina.

Hair cells in the cochlea.

Olfactory receptors in the nasal cavity.

Taste buds on the tongue.

Ion channels that open or close in response to stimuli, initiating sensory transduction.

Light-sensitive proteins in photoreceptors that play a key role in vision.

Sharp central vision with high acuity.

Detects motion and provides a broader field of view.

Processes sensory information to create perceptions and responses.

Voluntary muscles attached to bones.

Involuntary muscle found in the heart.

Involuntary muscles in the walls of internal organs.

Composed of myofibrils containing actin and myosin filaments.

The process where myosin heads bind to actin, pull, and release, powered by ATP.

Triggers muscle contraction by binding to troponin, which moves tropomyosin to expose binding sites on actin.

Muscle pairs that work opposite each other to move bones (e.g., biceps and triceps).

Oxygen is taken in, and carbon dioxide is expelled.

The process of moving air in and out of the lungs.

Extract oxygen from water.

Air-filled tubes in insects.

Organs for gas exchange in terrestrial animals.

Diaphragm contraction creates a vacuum that draws air into the lungs.

A protein in red blood cells that binds oxygen; its affinity for oxygen is affected by pH and CO2 levels.

Stores oxygen in muscle cells for use during intense activity.

Transports nutrients, gases, and wastes throughout the body.

Hemolymph bathes organs directly.

Blood is confined to vessels.

Pumps blood.

Carry blood away from the heart.

Return blood to the heart.

Sites of material exchange.

Path through the cardiovascular system, including the pulmonary and systemic circuits.

Occurs primarily in capillaries.

Coordinated by the sinoatrial (SA) node and atrioventricular (AV) node.

Eat plants.

Eat other animals.

Eat both plants and animals.

Carbohydrates, proteins, fats.

Required for various bodily functions.

Must be obtained from the diet.

Organic compounds needed in small amounts.

Lack of sufficient calories vs. lack of essential nutrients.

Taking in food.

Breaking down food into absorbable units.

Nutrients enter the bloodstream.

Expelling undigested material.

The digestive tract from mouth to anus.

Begins mechanical and chemical digestion.

Produce saliva to moisten food.

Prevent food from entering the trachea.

Secretes acid and enzymes to digest food.

Absorbs nutrients.

Produces digestive enzymes and bicarbonate.

Produces bile to emulsify fats.

Stores and releases bile.

Absorbs water and forms feces.

A vestigial structure with immune functions.

Nonspecific defense mechanisms.

Specific responses to pathogens.

Present on all nucleated cells; presents to cytotoxic T cells.

Present on antigen-presenting cells; presents to helper T cells.

Engulf and digest pathogens.

Present antigens to T cells.

First responders to infection.

Activate other immune cells.

Kill infected cells.

Destroy virus-infected and cancerous cells.

Produce antibodies.

Bind to antigens to neutralize them.

Recognize antigens presented by MHC molecules.

Signaling molecules that regulate immune responses.

Stimulate the immune system to develop immunity to specific pathogens.

Chemical messengers that regulate physiological processes.

Bind to receptors on the cell surface.

Pass through cell membranes and bind to intracellular receptors.

Include the pituitary, thyroid, adrenal glands, etc.

The hypothalamus controls the pituitary, which regulates other endocrine glands.

Parathyroid hormone increases blood calcium levels.

Mediated by the adrenal medulla (epinephrine and norepinephrine).

Mediated by the adrenal cortex (cortisol).

Highly toxic, requires a lot of water to excrete, common in aquatic animals.

Less toxic, requires less water, common in mammals, amphibians, and some fish.

Least toxic, conserves water, common in birds, reptiles, and insects.

Outer layer containing nephrons.

Inner region with renal pyramids.

Funnel-shaped structure that collects urine.

A network of capillaries where blood filtration begins.

Encases the glomerulus and collects the filtrate.

Reabsorbs nutrients, ions, and water from the filtrate.

Concentrates urine by reabsorbing water and salts.

Further adjusts the composition of the filtrate.

Final site for water reabsorption, leading to the renal pelvis.