Chapter 4: Cell Structure Flashcards
Genetic material
single circular molecule in prokaryotes
double helix located in nucleus in eukaryotes
Cytoplasm
Fills cell interior
Plasma membrane
Encloses the cell
Discovery of cells
In 1665 by Robert Hooke
Who proposed the Cell Theory?
Mathias Schleiden and Theodore Schwann
Cell Theory
All organisms are composed of one or more cells
Cells are the smallest living units
Cells arise only by division of a previously existing cell
What affects rate of diffusion?
Surface area
Temperature
Concentration gradient
Distance
What are the type of microscopes
Light and electron
Prokayotic Cells
Lacks nucleus- DNA is present as a nucleoid
Cytoplasm is surrounded by plasma membrane and encased in a rigid cell wall composed of peptidoglycan
Eukaryotic Cells
Characterized by compartmentalization by an endo membrane system, and the presence of membrane-bound organelles.
Plant Cell and Animal Cell
Nucleus
Inheritance, RNA production
Mitochondrion
Energy production
Endoplasmic reticulum
Protein and lipid production
Golgi
Glycosylation, secretion
Lysosomes
Degradation
Peroxisomes
Degradation, detoxification
How many pairs of chromosomes do humans have?
23
Histones
Packaging proteins
Endomembrane system
Divides cell in compartments where different cellular functions occur
Rough ER
Contains ribosomes
Smooth ER
Important in lipid synthesis
Ribomsomes
Made of ribosomal RNA and proteins
Site of protein synthesis
Assembled in nucleoli
Golgi Apparatus
Collection of Golgi bodies
Composed of Rough and Smooth ER
Collects, packages, and distributes molecules synthesized at one location in the cell and utilized at another location
Sugar production and addition to proteins and lipids to form glycoproteins and glycolipids
Stores secreted material
Lysosomes
Membrane-bound digestive vesicles
Destroy cells or foreign matter that the cell has engulfed by phagocytosis
Microbodies
Enzyme-bearing, membrane-enclosed vesicles
Peroxisomes
Contain enzymes that catalyze the removal of electrons and associated hydrogen atoms
Protect cell from toxin damage
Mitochondria
Interior partitioned by cristae
Power house of the cell (generates ATP for cellular function)
Chloroplasts
Have enclosed internal compartments of stacked grana, containing thylakoids and chlorophyll for photosynthesis
Cytoskeleton
Maintain cell shape Connect cells to each other Transport organelles and small molecules Provide cell motility Move chromosomes Compose cilia
Actin filaments
Globular protein actin, contraction, crawling or pinching
Microtubules
Centrioles, organization of cytoplasm and movement of cargo in the cell
Intermediate Filaments
Stable and do not break down, mechanical strength of the cell
Centrosomes
Region surrounding centrioles in almost all animal cells
Microtubule-organizing center
Kinesin
Moves vesicle towards the edge or periphery of the cell
Dynein
Moves cargo or vesicles toward the center of the cell