Chapter 4: Biology of the Cell Flashcards
three major structural components of a cell
- nucleus: largest structure in the cell
- plasma membrane
- cytoplasm:
cytoplasm is composed of:
cytosol: intracellular fluid
organelles: two categories:
**membrane-bound organelles:
**
endoplasmic reticulum
Golgi apparatus
lysosomes
peroxisomes
mitochondria
**Non-membraned-bound organelles:
**
ribosomes
cytoskeleton
centrosome
proteasomes
**
what are some membrane-bound organelles:
endoplasmic reticulum
Golgi apparatus
lysosomes
peroxisomes
mitochondria
non-membraned-bound organelles:
ribosomes
cytoskeleton
centrosome
proteasomes
**Membrane Proteins **
What are 2 Structural Types
Integral proteins: embedded with, and extend across the phospholipid bilayer
Peripheral proteins: reside on either the internal or external surface of the plasma membrane.
Membrane Transport:
movement of a substance from an area of greater concentrated —> Less
(passive or active)
Passive Processes: Diffusion
Membrane Transport (1/2)
expenditure of cellular energy and include both active transport and vesicular transport.
Active Processes
2 Types of Diffusiom
Simple diffusion and Facilitated diffusion
Simple diffusion-
unassisted movement of small and nonpolar molecules through the phospholipid bilayer.
Facilitated diffusion:
* transport of small charged or polar solutes that require assistance membrane proteins
- Channel-mediated facilitated diffusion
-Carrier-mediated facilitated diffusion -how glucose is transported into the cell
Facilitated- Faciliate Polar
(Carries Glucose into Cell)
simple- nonpolar
2 Types of Facilitated Diffusion
2 C’s
- Channel-mediated facilitated diffusion
-Carrier-mediated facilitated diffusion -how glucose is transported into the cell
(Carries Glucose into Cell)
isotonic:
hypotonic:
hypertonic:
isotonic: Cytosol & solution = same concentration of solutes
hypotonic:
low solutes, higher concentration of water (solvent) than in cytosol
hypertonic more solutes than cytosol
what moves (large) material secreted out of a cell?
what moves substances into a cell?
Exocytosis
Endocytosis (
three types of Endocytosis are:
Phagocytosis:
Pinocytosis:
Receptor-mediated
Endocytosis moves substances into a cell.
**Phagocytosis: **cellular eating
pinocytosis: cellular drinking
receptor-mediated
“phag- Fat”. “Pine- Pine Sol”
Rough ER
Smooth ER
Rough ER:
protein production by ribosomes
**Smooth ER:
synthesis, transport, and storage of lipids
carbohydrate metabolism
detoxification of drugs and poisons**
Smooth- skin, skin is fat, fat=lipid, fat= eating CARBS (Ca
Rough- Ribo
Golgi apparatus function
-Modification, packaging, and sorting of proteins
- Formation of secretory vesicles
Corgi-
Lysosomes function
Participate in digestion of unneeded substances
Peroxisomes (Function)
membrane bound
Metabolic functions include (include both digestion and synthesis):
role in chemical digestion
beta oxidation (oxi)
lipid synthesis
Endomembrane system
ER, Golgi apparatus, vesicles, lysosomes, peroxisomes]
mitochondria: complete digestion of fuel molecules to synthesize ATP (“Powerhouse” of the cell)
Non-Membrane-Bound Organelles
Ribosomes: (protein synthesis)
Cytoskeleton (support, cell division, transport)
Microfilaments
Intermediate filaments
Microtubules
Structures of the Cell’s External Surface
Cilia: sweep materials along the cell’s outer surface/ move fluid, mucus, and materials over the cell surface
Flagella:
located only on sperm, moves the sperm through the female reproductive tract.
Microvilli: increase cell surface area
gel=sperm
Transcription:
RNA is formed from DNA
Copy of a gene formed from DNA in nucleus
3 types: messenger (mRNA), transfer (tRNA), ribosomal (rRNA)
Requires DNA, free ribonucleotides, and the enzyme RNA polymerase.
Translation:
(making of a protein)
occurs in the cytosol and requires:
ribosomal RNA
Osmosis is a type of
passive transport
moves water, not solute
The net movement of a substance from high concentration to low is called ______.
Diffusion
______ move most easily across the phospholipid bilayer.
Small and nonpolar solutes
active transport
uses cellular energy
Transport (shuttle) vesicles are produced within a cell by ______.
rough ER
The structure of the ______ has been compared to a “warehouse” center where arriving molecules are modified, packaged, and then shipped out.
Golgi apparatus
Old or worn out organelles in a cell are removed by an organelle called the
Lysosome
Microvilli function to ______.
increase surface Area
Transcription is the formation of Blank______.
RNA
The process by which a DNA gene is copied into RNA is called ______.
Transcription
The organelle in which transcription takes place is the
Nucleus
The process that occurs on ribosomes by which a mRNA transcript is read and a new protein produced is called
Translation
