Ch 4 Powerpoint Part 2 Flashcards
What is cytosis?
Mechanism for bringing nutrients into the cell and ejecting waste
Requires ATP and has two types: endocytosis and exocytosis.
What are the two types of cytosis?
- Endocytosis
- Exocytosis
What is endocytosis?
Transports large particles or liquids into the cell by engulfing them
What are the two types of endocytosis?
- Phagocytosis (solid materials)
- Pinocytosis (liquid materials)
What is phagocytosis?
Engulfing of solid materials by cells, such as macrophages
What is pinocytosis?
Engulfing of liquid materials by cells
What is receptor-mediated endocytosis?
A type of endocytosis that involves specific receptors for the engulfed materials
What is exocytosis?
Cells export intracellular substances into the extracellular space
What packages substances for exocytosis?
Substances packaged in vesicles by the ER and Golgi body
What occurs during the mitotic phase of the cell cycle?
Cell division occurs
What are the two major periods of the cell cycle?
- Interphase
- Mitotic phase
What happens during interphase?
The cell is growing, maturing, and differentiating
What are the three sub-phases of interphase?
- Growth one (G1) phase
- Synthetic (S) phase
- Growth two (G2) phase
What occurs during the G1 phase of interphase?
Intensive metabolic activity and cellular growth
What happens during the S phase of interphase?
DNA replication
What occurs during the G2 phase of interphase?
Synthesis of enzymes and proteins necessary for cell division and continued growth
What is the purpose of DNA replication?
To create a perfect copy of DNA to pass on to daughter cells before cell division
What is the role of DNA polymerase III in DNA replication?
Places complementary nucleotides along the template strand and covalently links them together
What are telomeres?
Nucleoprotein caps placed on the ends of each DNA strand
What are chromatids?
Identical DNA strands jointed together at a centromere
What are the four stages of mitosis?
- Prophase
- Metaphase
- Anaphase
- Telophase
What happens during prophase?
Invisible chromatin strands condense to form discrete X-shapes and the nuclear envelope disintegrates
What occurs during metaphase?
Chromosomes line up in the exact center of the spindle at the metaphase plate
What happens during anaphase?
Chromatids are pulled apart by spindle fibers to form duplicate sets of chromosomes
What occurs during telophase?
Chromosomes begin to unravel, and the nuclear envelope reappears
What is cytokinesis?
The process of cytoplasmic division that marks the end of cell division
What are the mechanisms that control cell division?
- Contact inhibition
- Growth-inhibiting substances
- Checkpoints for cell assessment of the division process
- Cyclins
- Cyclin-dependent kinases (CDKs)
What is transcription in protein synthesis?
The process of making mRNA from the genetic info in DNA
What is translation in protein synthesis?
Making protein from mRNA templates
What are mutagens?
- Spontaneous mutations
- Viruses
- Ionizing radiation
- Chemicals
What is cell differentiation?
The process by which cells become specialized
Fill in the blank: All living, breathing, thinking animals begin life as a _______.
single cell
