Ch 4 - Cells Physiology Flashcards
What is the definition of normal hydration?
Consuming the same amount of water that is lost
This includes taking in water through moist foods and drinking fluids.
What is metabolic water?
Water produced from the oxidation of nutrients
It is a source of water for animals.
What is insensible water loss?
Water loss that cannot be measured
Examples include diffusion from the skin.
What are the two main types of body fluids?
- Intracellular fluid
- 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 significance of pH in body fluids?
Indicates acidity or alkalinity of a solution
Pure water is neutral (pH 7), while blood is slightly alkaline (pH 7.4).
True or False: Blood has a pH of 7.
False
Blood has a pH of approximately 7.4.
What is osmolality?
Measurement of solute concentration in 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 to cells in hypotonic fluids?
Cells swell and may break
This occurs because the cytoplasm is more concentrated than the extracellular fluid.
What happens to cells in hypertonic fluids?
Cells shrink and become shriveled
This is due to water shifting into the extracellular space.
What are the two main categories of solutes in body fluids?
- Electrolytes
- Organic molecules
Electrolytes are small and abundant, while organic molecules include proteins and lipids.
Fill in the blank: Any change in the concentration of any solute incurs movement of water from one compartment to another through _______.
Osmosis
What is edema?
Abnormal, excess accumulation of fluid in tissue
Common types include pulmonary edema and cutaneous edema.
What are the two types of fluid therapy?
- Crystalloids
- Colloids
Crystalloids are rich in electrolytes, while colloids contain larger molecules.
What is the goal of administering fluids in dehydration?
To increase fluid volume
This involves estimating dehydration and fluid deficit.
What are the two main types of membrane processes?
- Passive processes
- Active processes
Passive processes do not require energy, while active processes do.
What is diffusion?
Kinetic movement of molecules from higher to lower concentration
It occurs along a concentration gradient.
What is facilitated diffusion?
Movement of molecules assisted by carrier proteins
It requires no energy and is limited by the number of carrier proteins.
What is osmosis?
Passive movement of water through a semipermeable membrane
Water moves from a dilute solution to a more concentrated one.
What is oncotic pressure?
The difference between osmotic pressure of blood and interstitial fluid
It is crucial for maintaining fluid balance.
What is the main purpose of active transport?
To move molecules against a concentration gradient using energy
It is essential for transporting amino acids and ions.
What are the two types of cytosis?
- Endocytosis
- Exocytosis
Endocytosis involves bringing substances into the cell, while exocytosis involves exporting substances.
What are the two types of endocytosis?
- Phagocytosis
- Pinocytosis
Phagocytosis involves solid materials, while pinocytosis involves liquids.
What occurs during the mitotic phase of the cell cycle?
The cell is actively dividing
This phase includes prophase, metaphase, anaphase, and telophase.
What are the three sub-phases of interphase?
- Growth 1 (G1) phase
- Synthetic (S) phase
- Growth 2 (G2) phase
Interphase is the period between cell divisions.
What occurs during DNA replication?
A perfect copy of DNA is created for daughter cells
This involves uncoiling the DNA and synthesizing new strands.
What are chromatids?
Identical DNA strands joined together at a centromere
They are produced during DNA replication.
What is cytokinesis?
Division of the cytoplasm during cell division
It follows the four stages of mitosis.
What is the process of cell division called?
Mitosis
Mitosis is the process by which a single cell divides to produce two identical daughter cells.
What stage of mitosis involves the condensation of chromatin into discrete X-shaped structures?
Prophase
In prophase, chromatin condenses, spindle apparatus forms, and the nuclear envelope disintegrates.
What happens during metaphase?
Chromosomes line up at the metaphase plate
The centromere of each chromosome attaches to a single spindle fiber.
What is the process called when chromatids are pulled apart during mitosis?
Anaphase
In anaphase, chromatids are separated by spindle fibers, creating duplicate sets of chromosomes.
What occurs during telophase?
Chromosomes begin to unravel and the nuclear envelope reappears
Telophase marks the final stage of mitosis where chromosome movement stops.
The division of cytoplasm is known as?
Cytokinesis
Cytokinesis signifies the end of cell division, resulting in two distinct cells.
What factors control cell division?
Contact inhibition, growth-inhibiting substances, checkpoints, cyclins, cyclin-dependent kinases (CDKs)
These factors ensure proper regulation of the cell division process.
What is transcription in protein synthesis?
The process of making mRNA from DNA
RNA polymerase binds to DNA, separates the double helix, and creates mRNA.
What is translation in protein synthesis?
Making protein from mRNA templates
Translation occurs in the cytoplasm where ribosomes synthesize proteins based on mRNA.
What are genetic mutations?
Errors in genetic replication
Mutagens can cause mutations, including spontaneous mutations, viruses, ionizing radiation, and chemicals.
What is cell differentiation?
The process by which cells become specialized
Cell differentiation begins from a single cell and involves the turning on or off of specific genes.
Fill in the blank: During mitosis, the _______ is the stage where chromosomes align in the center.
Metaphase
Metaphase is characterized by chromosomes lining up at the metaphase plate.
True or False: In telophase, the chromosomes start to condense.
False
In telophase, chromosomes unravel and return to a threadlike form.
