Chapter 3 Flashcards
type of cells that are reproductive cells; consist of the male sperm and female oocyte
sex cells
all body cells except sex cells
somatic cells
comprises of the cytosol and the organelles;
cytoplasm
Essential for movement of chromosomes during cell division; organization of
microtubules in
cytoskeleton
centrosome and centrioles
Proteins organized in fine filaments or slender tubes and functions in strength and support, and movement of cellular structures and materials
cytoskeleton
Lipid bilayer containing phospholipids, steroids, proteins, and carbohydrates; Functions in isolation, protection, sensitivity, support, and control of entry
and exit of
materials
plasma membrane
Membrane extensions
containing microfilaments which functions to increase surface area to facilitate
absorption of extra-cellular
materials
microvilli
Long extensions
containing microtubule doublets in a 9 + 2 array and functions in movement of material over cell surface
cilia
Hollow cylinders of proteolytic enzymes with regulatory proteins at their ends; Functions in breakdown and recycling of
damaged or abnormal intracellular proteins
proteasomes
RNA + proteins;
bound to rough endoplasmic
reticulum or scattered in cytoplasm; functions in protein synthesis
ribosomes
Stacks of flattened membranes (cisternae) containing chambers; functions in storage, alteration, and packaging
of secretory products and
lysosomal enzymes
Golgi apparatus
Double membrane, with inner membrane folds (cristae) enclosing important metabolic enzymes;
Produce 95% of the ATP
required by the cell
mitochondria
Modifies and packages newly synthesized proteins
rough ER
Synthesizes lipids and
carbohydrates
smooth ER
Vesicles containing
degradative enzymes which functions in catabolism of fats and other organic compounds, neutralization of toxic compounds generated in the process
peroxisomes
Vesicles containing
digestive enzymes which functions in intracellular removal of damaged organelles or pathogens
lysosomes
Nucleoplasm containing nucleotides, enzymes, nucleoproteins, and chromatin; surrounded by a double membrane, the nuclear envelope. This structure controls metabolism, storages and processes genetic information and controls protein synthesis
nucleus
site of rRNA synthesis and
assembly of ribosomal
subunits
Nucleolus
A watery medium that surrounds a cell
Extracellular Fluid (Interstitial Fluid)
What is the phospholipid bilayer made of?
Hydrophilic heads and Hydrophobic fatty-acid tails
Membrane protein within the membrane
Integral Protein
Membrane protein bound to inner or outer surface of the membrane
Peripheral Proteins
Membrane protein that attaches h to inside or outside structures
Anchoring Proteins
stabilizers
Membrane protein that label cells as normal or abnormal
Recognition Proteins (identifiers)
Membrane proteins that catalyzes reactions
Enzymes
Membrane proteins that bind and respond to
ligands
(ions, hormones)
Receptor Proteins
Membrane proteins that transport specific solutes through membrane
Carrier Proteins
Membrane proteins that regulate water flow and solutes through
membrane
Protein Channels
Sticky “sugar coat” that is formed by proteoglycans, glycoproteins, and glycolipids
glycocalyx
Functions of the glycocalyx
• Lubrication and Protection • Anchoring and Locomotion • Specificity in Binding (receptors) • Recognition (immune response)
Type of organelles that have no membrane and has direct contact with cytosol
Nonmembranous organelles
Examples of nonmembranous organelles
cytoskeleton, microvilli, centrioles, cilia, ribosomes, and proteasomes
Type of organelles that are covered with plasma membrane and isolated from cytosol
Membranous organelles
Examples of membranous organelles
endoplasmic reticulum (ER), the Golgi apparatus,
lysosomes, peroxisomes,
and mitochondria
three structural proteins that make up the cytoskeleton
- Microfilaments
- Intermediate filaments
- Microtubules
thin filaments composed of the protein actin; they provide additional mechanical strength and
Interact with proteins for consistency;
Pair with thick filaments of
myosinfor muscle movement
Microfilaments
mid-sized filaments in comparison to microfilaments and thick filaments; they are
durable (collagen) and they
strengthen cell and maintain shape, stabilize organelles and stabilize cell position
Intermediate filaments
large, hollow tubes of tubulin protein that • Attach to centrosome • Strengthen cell and anchor organelles • Change cell shape • Move vesicles within cell (kinesin and dynein) • Form spindle apparatus
Microtubules
Filaments composed of myosin protein in muscle cells
Thick filaments
Ribosomes in cytoplams that manufacture proteins for cell
Free ribosomes
Ribosomes attached to
ER that manufacture proteins for secretion
Fixed ribosomes
Functions of Smooth ER
- Synthesizes lipids and carbohydrates
- Phospholipids and cholesterol (membranes)
- Steroid hormones (reproductive system)
- Glycerides (storage in liver and fat cells)
- Glycogen (storage in muscles)
Functions of Rough ER
• Active in protein and glycoprotein synthesis
• Folds polypeptide protein structures
• Encloses products in
transport vesicles
Type of lysosome formed by Golgi apparatus and inactive enzymes
Primary lysosome
Lysosome fused with damaged organelle which activates digestive enzymes and isolates toxic chemicals
Secondary lysosome
Functions of lysosomes
- Clean up inside cells
2. Autolysis
Self-destruction of damaged cells
Autolysis
Double membrane around the nucleus
Nuclear envelope
Space between the two layers of the nuclear envelope
Perinuclear space
Communication passages in the nucleus
Nuclear pores
Fluid containing ions, enzymes, nucleotides, and
some RNA
Nucleoplasm
Support filaments in the nucleus
Nuclear matrix
related to protein production and are made of RNA, enzymes, and
histones; they synthesize rRNA and ribosomal subunits
Nucleoli
DNA coiled around histones
Nucleosomes
Loosely coiled DNA (cells not dividing)
Chromatin
Tightly coiled DNA (cells dividing)
Chromosomes
Instructions for every protein in the body
DNA
DNA instructions for one protein
Gene
The chemical language of DNA instructions
Genetic code
Consists of 3 bases that code for 1 amino acid
Triplet code
Process involving uncoiling of DNA with the use of promoters and terminators
Gene activation
Process involving copying instructions from DNA to mRNA
Transcription
produces messenger RNA (mRNA)
RNA polymerase
process by which ribosome reads code from mRNA (in cytoplasm) and assembles amino acids into polypeptide chain
Translation
Three steps to transcribe a gene to mRNA
- Gene activation
- DNA to mRNA
- RNA processing
What happens during gene activation?
• Uncoils DNA, removes histones
• Start (promoter) and stop codes on DNA mark
location of gene
Strand that codes for protein
coding strand
strand used by the RNA polymerase molecule
Template strand
Unnecessary gene codes
introns
Good genetic codes in mRNA
exons
Triplet of three nucleotides
codon
What happens during Translation?
- mRNA moves from the nucleus through a nuclear pore
- mRNA moves to a ribosome in cytoplasm surrounded by amino acids
- mRNA binds to ribosomal subunits where tRNA delivers amino acids to mRNA
Property that determines what moves in and out of a cell
Permeability
A membrane that lets nothing in or out is said to be?
impermeable
A membrane that lets anything pass is said to be?
freely permeable
A membrane that restricts movement is said to be?
selectively permeable
Transport requiring energy and ATP
Active
Transport with no energy required
Passive
the process in which the solute move from high
and low concentrations
Diffusion
Factors influencing Diffusion
- Distance
- Molecule Size
- Temperature
- Concentration Gradient
- Electrical Forces
type of diffusion that diffuses lipid soluble compounds and dissolved gases through plasma membrane
simple diffusion
type of diffusion that diffuses water-soluble compounds and ions through plasma membrane
Channel-mediated diffusion
the diffusion of water across the cell membrane
Osmosis
A solution that does not cause osmotic flow of water in or out of a cell
Isotonic
Has less solutes and loses water through osmosis
Hypotonic
Has more solutes and gains water by osmosis
Hypertonic
Type of carrier-mediated transport where two substances move in the same direction at the
same time
Cotransport
Type of carrier-mediated transport where one substance moves in while another moves out
Countertransport
Proteins that move substrates against concentration gradient
Active transport proteins
Active transport, carrier mediated where sodium ions (Na+) moves out, potassium ions (K+) moves in; 1 ATP moves 3 Na+ and 2 K
Sodium–potassium exchange pump
Forms when an abnormal cell grows and divides out of control
tumor/neoplasm
tumor that do not become invasive
benign tumor
neoplastic cells of a tumor invade surrounding tissue
cancer
forms when invasiveness allows the cancer cells to break loose, enter blood or lymphatic vessels
secondary tumor (metastases)
