Lecture #6 Chapter #3 Flashcards
What is the cytoskeleton made of?
Microfilaments, microtubules, and intermediate filaments
What ate the 4 functions of the cytoskeleton?
Provide strength, provide the cell with ability to resist force, maintain shape, and sell motility
What is the location of the cytoskeleton?
Throughout the cell
What are microfilaments?
Tiny rods of protein (beta actin)
What are microtubules?
Slender tubes composed of pairs of (tubulin)
What are intermediate filaments?
Several types of proteins (keratin)
What is cell motility?
Cell rearranging it self to move
What is phalloiden?
A toxin that binds to f-actin and can be used with a fluorescent molecule to monitor changes in microfilament organization
What is the central zone composed of?
Two cylinders called centrioles
What is the function of the centrisome?
Centrioles migrate to either side of the nucleus and produce spindle fibers to pull and distribute chromosomes to newly forming cells
Where is the central zone located?
Near the nucleus
How can centrioles be thought of?
Like a factory because they can assemble and disassemble the cytoskeleton
What are cilia and flagella made of?
Microtubules
What is the function of cilia and flagella?
Motility
What is the difference between cilia and flagella?
Cilia perform sweeping movements while the cell remain stationary
Flagella perform swimming movements while the cell propels in specified direction
Where are flagella located?
Sperm cell
Where are cilia located?
In many different locations such as the respiratory track in the fallopian tubes
What happens during interphase?
Cell growth, maintenance of routine functions, and replication of all DNA
What are the three phases that interphase can be subdivided into?
G1 phase-growth phase
S phase–DNA replicated
G2 phase-cellular growth, synthesize of structures besides DNA

What does the G stand for in G1 and G2 phase?
Gap
What does the S stand for in the S phase?
Synthesis
What are the 3 main phases of the cell cycle?
Interphase, mitosis, and cytokinesis
What are somatic cells?
Normal cells which are not sex cells
Where does meiosis occur?
Only in sex cells
And what types of cells are 23 chromosomes found?
Sex cells
In what type of cells are 46 chromosomes found?
Somatic cells
What is the nuclear envelope?
The nuclear membrane
In which type of cells does mitosis occur?
Somatic/non-sex cells
What is produced at the end of mitosis?
Two identical daughter cells from the original cell eats with a complete set of 46 chromosomes. With 23 coming from each parent
How many chromosomes are in meiosis?
23
What are the four phases of mitosis?
Prophase, metaphase, anaphase, and telophase
What 4 things happen in prophase?
-Chromatin condenses
-Sister chromatids attached at the centromere
-Centrioles move to opposite sides of the nucleus in micro tubules form
-The nuclear envelope and nucleolus break apart
What 2 things happen in metaphase?
-Duplicated Homologous chromosome’s lineup at the spindle equator (halfway between spindle polls)
-Sister chromatids prepare to move apart toward opposite spindle poles
What happens in anaphase?
-Microtubules separate the sister chromatids of each chromosome and pull them toward opposite spindle poles
-Each DNA molecule is now a separate chromosome
What happens in telophase?
To clusters of chromosomes arrive at the spindle polls in decondense; new nuclei form
What happens at the end of mitosis?
Cytokinesis, which is when nuclear envelopes form around the two clusters of chromosomes forming two new nuclei with the parental chromosome number
What causes a tumor?
To frequent mitosis – abnormal growth
What stages of the cell cycle are skipped in cancer?
G1 and G2 checkpoints are ignored
What is a neoplasm?
Moles and other tumors
Abnormal masses of tissue
What is a benign tumor?
A non-cancerous neoplasm
What is a malignant neoplasm?
Cancer when abnormally dividing cells disrupt body tissues, physically and metabolically
What is a tumor suppressor gene?
A gene that holds mitosis in check
What is an oncogene?
Abnormal variance of genes that normally control the cell cycle but become overexpressed and increase cell division rate
What does metastasize mean?
Malignant neoplasms can break free and invade other tissues
What is BRCA gene?
Breast cancer genes are tumor suppressor genes whose products normally repair broken DNA
What are the two ways that a cell dies?
Apoptosis and necrosis
What occurs in apoptosis?
Programmed cell death which occurs normally with the formation of blebs
What is a bleb?
 Bulges of packaged contents during apoptosis
What is necrosis?
Cell death from damage which does not occur normally and releases Inflammatory cellular contents
What is diffusion?
Net movement of substances is down a concentration gradient which ends in dynamic equilibrium
What are the two types of proteins and facilitated diffusion?
Channel and carrier proteins
What happens in facilitated diffusion?
Substances which do not readily diffuse across the membrane are transported via proteins to allow diffusion to occur
What must be done to move substances up a concentration gradient?
Active transport
What happens in active transport?
Energy is used where to solutes are typically pumped across the membrane in the opposite direction
What is osmosis?
Where water moves to the concentration of high solvent
What is filtration?
Forcing molecules through membranes by exerting pressure
What is filtration used for?
To separate solids from water
What is endocytosis?
Cells taking in macromolecules by forming new vesicles from the plasma membrane
What is exocytosis?
Vesicles migrate to the plasma membrane, fused with it, and release their contents
What is pinocytosis?
Drinking/Taking in water and dissolved components
What is phagocytosis?
Eating/Taking in solids
What is receptor mediated endocytosis?
The taking in of specific molecules from surrounding fluids that bind to receptors
What are examples of exocytosis?
Releasing neural transmitters and some hormones
What is transcytosis?
The combining of endocytosis and exocytosis to selectively and rapidly transport a substance or particle from one end of a cell to another
