Ch 4 Powerpoint Part 1 Flashcards
What is the definition of normal hydration?
Consuming the same amount of water that is lost.
This includes water intake from moist foods and drinking fluids.
What is metabolic water?
Water produced from metabolic processes, specifically oxidation.
It is considered a source of water intake in animals.
What is insensible water loss?
Water loss that cannot be measured, such as diffusion from the skin.
Examples include sweating and vocalizing.
What are the two main types of body fluids?
Intracellular fluid and extracellular fluid.
Extracellular fluid includes intravascular and interstitial fluid.
What are electrolytes?
Particles in body fluids capable of conducting an electrical current.
They include cations, anions, acids, and bases.
What is the pH of pure water?
7 (neutral).
Blood has a pH of 7.4, while gastric juice has a pH below 7.
What can affect normal body functions?
Changes in electrolyte concentrations and pH.
This includes effects on nerve impulses, muscle contraction, and respiration.
What does osmolality measure?
The concentration of solutes in a fluid.
High osmolality indicates a high concentration of solutes.
What is isotonic fluid therapy?
Fluid with osmolality comparable to that of normal blood.
Example: 0.9% NaCl (normal saline).
What happens with hypotonic fluids?
Osmolality is less than that of blood, causing cells to swell.
Water flows into the cell, which may lead to rupture.
What happens with hypertonic fluids?
Osmolality is greater than that of blood, causing cells to shrink.
Water shifts into the extracellular space.
What are the two main categories of solutes in body fluids?
Electrolytes and organic molecules.
Electrolytes are small and abundant, while organic molecules are large and less numerous.
What is edema?
Abnormal, excess accumulation of fluid in tissue.
Common signs include pulmonary and cutaneous edema.
What are the three phases of fluid therapy?
Resuscitation, replacement, maintenance.
What is passive membrane process?
Absorption of nutrients or excretion of waste without energy expenditure.
Examples include diffusion and osmosis.
What is diffusion?
Movement of molecules from higher to lower concentration.
It is driven by the concentration gradient.
What is facilitated diffusion?
Movement of molecules assisted by selective carrier proteins.
Example: Glucose moving into muscle cells.
What is osmosis?
Passive movement of water through a semipermeable membrane from dilute to concentrated solution.
It aims to achieve concentration balance.
What is oncotic pressure?
The difference between osmotic pressure of blood and interstitial fluid.
It is important for maintaining fluid balance.
What is filtration?
Movement of liquids through a membrane based on a pressure gradient.
Hydrostatic pressure is a key factor.
What is active transport?
Movement of molecules across the cell membrane using energy (ATP).
It is necessary for certain amino acids and ions.
What is endocytosis?
Transport of large particles or liquids into the cell by engulfing them.
Types include phagocytosis and pinocytosis.
What is cytokinesis?
Division of the cytoplasm during cell division.
It follows mitosis.
What are the phases of interphase?
Growth 1 (G1), synthetic (S), growth 2 (G2).
Interphase is the period between cell divisions.
What occurs during DNA replication?
DNA uncoils and separates to create a perfect copy for daughter cells.
This involves enzymes like DNA Polymerase III.
What are chromatids?
Identical DNA strands jointed together at a centromere.
They are formed during DNA replication.
What is the role of telomeres?
Nucleoprotein caps placed on the ends of each DNA strand.
They protect the DNA during replication.
What is the primary function of exocytosis?
Exporting intracellular substances into the extracellular space.
This includes the release of hormones and mucus.
What is the difference between somatic cells and reproductive cells?
Somatic cells are all body cells except reproductive cells; reproductive cells are involved in meiosis.
Somatic cells undergo mitosis.
How many stages are in mitosis?
Four stages: prophase, metaphase, anaphase, telophase.
What is mitosis?
The process of cell division that results in two identical daughter cells.
What occurs during prophase?
Invisible chromatin strands condense to form discrete X-shapes, spindle apparatus forms, and the nuclear envelope disintegrates.
What is the term for the division of cytoplasm?
Cytokinesis.
What happens during metaphase?
Chromosomes line up in the exact center of the spindle at the metaphase plate.
Fill in the blank: During metaphase, the centromere of each chromosome is attached to a single _______.
spindle fiber.
What occurs during anaphase?
Chromatids are pulled apart by spindle fibers to form a duplicate set of chromosomes.
What marks the beginning of telophase?
Chromosome movement stops.
What happens to the chromosomes during telophase?
Chromosomes begin to unravel and return to a threadlike form.
What is the role of microfilaments during telophase?
They begin to squeeze the cell into two parts.
What is cytokinesis?
The process of cytoplasmic division marking the end of cell division.
What is contact inhibition?
A mechanism that prevents cells from dividing when they are in contact with each other.
What are cyclins?
Proteins that regulate the cell cycle.
What are cyclin-dependent kinases (CDKs)?
Enzymes that, when activated by cyclins, can phosphorylate target proteins to regulate the cell cycle.
Define transcription.
The process of making mRNA from a DNA template.
What is translation in protein synthesis?
The process of making protein from mRNA templates.
What initiates the process of transcription?
RNA polymerase binds to the DNA molecule.
What are mutagens?
Agents that cause genetic mutations.
Fill in the blank: Genetic mutations can occur due to _______ replication errors.
genetic.
What is cell differentiation?
The process by which cells become specialized in structure and function.
What triggers the process of differentiation?
Temporary or permanent inhibition of genes that may be active in other cells.
How do cells divide to achieve differentiation?
A single cell divides to become two, then four, and so on, leading to greater specialization.
