Untitled Flashcards Set

What is the basic unit of life?

The cell is the basic unit of life.

What are the four primary types of tissue?

Muscle, nervous, epithelial, and connective.

What is an organ?

An organ is made up of several tissue types.

What is the lumen?

The lumen is the cavity within a hollow organ or tube.

What are exocrine glands?

Glands that secrete through ducts to the outside of the body.

What do endocrine glands do?

They release hormones internally into the blood.

What is homeostasis?

Processes to maintain a relatively stable internal environment.

What is intracellular fluid (ICF)?

The fluid inside of our cells.

What is extracellular fluid (ECF)?

The fluid outside of our cells.

What is the main compartment of extracellular fluid?

Plasma.

What are interstitial fluids?

Isolated pockets of extracellular fluid.

Where is sodium concentration high?

Sodium concentration is high outside the cell.

Where is potassium concentration high?

Potassium concentration is high inside the cell.

What does negative feedback do?

It moves the variable in the opposite direction of the stimulus.

What is an example of negative feedback in temperature control?

The thermostat system for controlling room temperature.

What is positive feedback?

The output enhances or amplifies a change.

What is feedforward control?

Initiates responses in anticipation of a change.

What is the integrating center in a control system?

The part that processes information and determines the response.

Where is the body's thermoregulation center?

The hypothalamus regulates body temperature.

What do central thermoreceptors monitor?

Core temperature.

What is an effector?

A component of the control system that brings about the desired effect.

What is the effector when sweating?

Sweat glands.

What happens in response to cold exposure?

Shivering and vasoconstriction in the skin.

What is the purpose of non-shivering thermogenesis?

To generate heat without shivering.

What happens when the temperature is too high?

Sweating and vasodilation in the skin.

What is pyrogens' role in fever?

They reset the set point in the hypothalamus.

Where do pyrogens come from?

From certain bacterial infections and somatic cells.

What is heat exhaustion?

A state of collapse usually manifested by fainting and profuse sweating.

What is hyperthermia?

Rapidly rising body temperature without sweating.

What is the primary blood sugar molecule?

Glucose.

What is glycogen?

The storage form of blood sugar in humans.

What do beta cells secrete when blood sugar is high?

Insulin.

What do alpha cells secrete when blood sugar is low?

Glucagon.

What is the role of insulin?

To lower blood glucose levels.

What are the three prime target cells for insulin?

Liver cells, skeletal muscle cells, and adipose tissue.

What does glucagon do?

Raises blood glucose levels.

What is diabetes mellitus?

A condition characterized by high blood sugar levels.

What is Type 1 Diabetes?

An autoimmune disease causing insulin deficiency.

What is Type 2 Diabetes?

A condition where body cells become insulin resistant.

What is gestational diabetes?

Diabetes that occurs during pregnancy.

What role do mitochondria play in a cell?

They generate ATP.

How does ATP provide energy to the cell?

By splitting high-energy phosphate bonds.

What is the process of glycolysis?

Conversion of glucose to pyruvate in the cytoplasm.

What is the Krebs cycle?

A series of reactions that produce NADH and ATP in the mitochondria.

What happens in the electron transport chain?

NADH and FADH2 donate electrons for ATP production.

What is the function of NADH and FADH2?

To transport electrons to the electron transport chain.

What is aerobic metabolism?

Metabolism that requires oxygen.

What happens during anaerobic metabolism?

Lactate is produced when oxygen is not available.

What is osmosis?

The movement of water across a selectively permeable membrane.

What does tonicity refer to?

The effect of a solution on cell size.

What is isotonic solution?

A solution that does not change cell size.

What does a hypertonic solution do to cells?

Causes cells to shrink.

What is endocytosis?

Transport of substances into a cell.

What is exocytosis?

Transport of substances out of a cell.

What are the formed elements of blood?

Platelets, white blood cells, and red blood cells.

What is hematocrit (HCT)?

Percentage of blood volume occupied by red blood cells.

What is erythropoiesis?

The process of red blood cell production.

What stimulates erythropoiesis?

Erythropoietin (EPO) in response to low oxygen.

What is anemia?

A condition where the blood does not carry enough oxygen.

What is polycythemia?

A condition with too many circulating red blood cells.

What is the primary job of blood?

To transport substances throughout the body.

What are signal molecules also known as?

Ligands.

What is the role of first messengers?

They bind to receptors on the cell membrane.

What is the function of second messengers?

They amplify and transmit the signal inside the cell.

What does phosphorylation do?

It activates proteins by adding a phosphate group.

What is the purpose of the sodium-potassium pump?

To maintain sodium and potassium gradients across the membrane.

What is the resting membrane potential typically around?

-70 mV.

What is Nernst equation used for?

To calculate the equilibrium potential for ions.

What determines the membrane potential?

The separation of charges across the membrane.

What does the term depolarization mean?

A decrease in membrane potential towards zero.

What does repolarization refer to?

A return of the membrane potential to resting state after depolarization.

What does action potential represent?

A rapid change in membrane potential that travels along the nerve cell.

What factors affect the rate of diffusion?

Concentration gradient, surface area, and permeability.

What is the role of aquaporins?

Channel proteins that facilitate water transport.

What is facilitated diffusion?

Transport of molecules across the cell membrane via a specific carrier.

What is the resting membrane potential primarily influenced by?

Potassium ions (K+).

What is the plasma membrane's primary function?

To regulate the movement of substances in and out of the cell.

What is the difference between simple diffusion and facilitated diffusion?

Simple diffusion does not require a carrier protein, while facilitated diffusion does.

What is the role of cholesterol in the cell membrane?

To maintain fluidity and stability.

What is the primary function of ribosomes?

To carry out protein synthesis.

What is the basic structure of a phospholipid?

A hydrophilic head and two hydrophobic tails.

What do tight junctions do?

Prevent the passage of materials between cells.

What do desmosomes do?

Provide structural support to tissues under mechanical stress.

What role do gap junctions play?

Allow communication and transfer of ions and small molecules between cells.

What is the primary role of blood?

Transport nutrients, oxygen, and waste products.

What do leukocytes do?

Defend against foreign invaders.

What is the function of platelets?

Involved in blood clotting.

What causes jaundice?

Bile in the blood due to liver issues.

What is the function of transferrin?

Transport iron in the bloodstream.

What is bilirubin?

A breakdown product of hemoglobin.

What is the role of lysosomes?

To break down organic molecules and worn-out organelles.

What does the term 'selectively permeable' mean regarding the plasma membrane?

It allows certain substances to pass while blocking others.

What happens during depolarization of the membrane potential?

The inside of the cell becomes more positive.

What is hyperosmotic?

A solution with a higher osmolarity than another.

What happens to a cell placed in a hypotonic solution?

It swells as water enters the cell.

What is the function of secretory vesicles?

They contain substances to be secreted from the cell.

What does membrane permeability refer to?

The ability of substances to cross the cell membrane.

What is a primary active transport mechanism?

Moves substances against their concentration gradient using ATP.

What is secondary active transport?

Moves substances against their concentration gradient indirectly using the gradient of another substance.

What is a cotransporter?

A protein that moves two substances simultaneously across a membrane.