Bio Chapter 4 Flashcards
What is one major difference between prokaryotic cells and eukaryotic cells?
Prokaryotes do not have a nucleus
Eukaryotes do have a nucleus
Rough endoplasmic reticulum
Modifies proteins made by ribosomes attached [from nucleolus] to it. Also folds polypeptides into their 3D tertiary form.
Involved in protein synthesis and sorting
Smooth Endoplasmic reticulum
System of internal membranes that aid in the manufacture of lipids and carbohydrates.
Detoxification, carbohydrate metabolism, calcium balance, synthesis and modification of lipids.
Endomembrane system
A multifunctional network of membrane-enclosed organelles that occur throughout a cells cytoplasm [vacuoles, nucleus, lysosomes, endoplasmic reticulum and Golgi body’s]
Chromosome
A single DNA molecule with its attached proteins. During cell division, chromosomes condense and become visible in micrographs.
Golgi body
Finishes, sorts, and ships lipids, enzymes and proteins; collects, packages, and distributes molecules manufactured in the cell.
Vesicles transport materials between sacs
Lysosome
Digests, recycles material; vesicle that breaks down macromolecules and digests worn out cell components.
Contains acid hydrolases [enzymes that preform hydrolysis]
Autophagy—> recycling of worn out organelles through endocytosis
Endoplasmic reticulum
An extension of the nuclear envelope that forms a continuous folded compartment.
Chromatin
All the DNA and its associated proteins in the nucleus. [non condensed chromosome, looks like spaghetti]
Is chromatin in prokaryotes?
No, only in eukaryotes because they have a nucleus.
Nucleolus aka nucleoli
A dense region in the nucleus where subunits of ribosomes are assembled from proteins and RNA.
Nucleus
Contains genetic material [eukaryotes only].
Nuclear envelope
Two lipid bilayers pressed together as a single membrane surrounding the nucleus [outer bilayer is continuous with the ER].
Nuclear pore
Opening embedded with proteins that regulates passage into and out of the nucleus [allows certain substances to pass through the membrane].
Translation
Process of polypeptide synthesis. Information within a gene is ultimately translated into the sequence of amino acids in a polypeptide.
Ribosome
Site of protein synthesis [made of RNA and proteins].
Transfer RNA [tRNA]
Brings amino acids.
Messenger RNA [mRNA]
Information to make a polypeptide.
Vacuole
Storage [typically water and food]
Large membrane sack
Vesicle
Transporting, storing, or digesting substances in a cell.
Small membrane sack
Compartmentalization
[many membrane bound organelles] allows different cell functions to occur in different areas of the cell.
Centriole
Complex assembly of microtubules that occurs in pairs [2]
Organizing microtubules that serve as the cells skeletal system
Mitochondria
Produces ATP by aerobic respiration. Organelle in which energy is extracted from glucose per during oxidative metabolism.
Cytoskeleton
Supports organelles and cell shape, and plays a role in cell motion.
What are the 3 proteins involved in the cytoskeleton?
Microtubules
Intermediate filaments
Microfilaments
Microtubules
Made of TUBLIN. Helps with the transport of substances within a cell [acts as a highway system].
Long, hallow cylinder structures. Dynamic instability- grow and shorten-mitosis
Initiate from centrosome
Microtubules make up………?
Cilia, flagella and other hairlike structures.
Intermediate filaments
Made of ACTIN. Maintain cell and tissue structure, provide support and strength.
Form twisted, rope like structures; stable
Microfilaments aka actin filaments
Made of ACTIN. Make up the cell cortex, responsible for cell movement [cell division].
Long, thin fibers; dynamic structures
Plasma membrane
Made of lipid bilayer. All cells have it. This controls substances passing in and out of the cell.
Selectively permeable
Cell signaling [using protein receptors]
Changes in the environment
Cell communication
Cell adhesion
Cytoplasm
A semi fluid mixture containing cell components.
Organelles
Structures that Carry out special metabolic functions inside a cell.
Membrane-enclosed organelles
Compartmentalization tasks such as:
Building
Modifying
Storing substances
Cell theory
Cells are fundamental units of life
Organisms consist of one or more cells
Smalles unit of life
Cells arise form cell division
Hereditary material passes to offspring
Phase-contrast light microscope
Yield high contrast images of transparent specimens. Darks areas have taken up the eye.
Reflected light microscopes
Capture light reflected from the surface of specimens.
Fluorescent lmicroscope
Shows fluorescent light emitted by chlorophyll molecules in the cell.
Transmission electron microscope
Reveals detailed images of internal structures.
Scanning electron microscopes
Show surface details. May be artificially colored to highlight specific details.
Nucleoid
A dense region of DNA in a prokaryotic cell.
Cell wall
Rigid and supports protection, not all cells have this. Plant cells and prokaryotes have this.
Glycocalyx
Viscous covering; traps water, protection from drying.
Capsule
Very thick glycocalyx; helps prokaryotes stick to each other and to various surfaces in their environment, helps prevent cell from drying out.
Appendages
Limbs
Flagellum [flagella]
Leg, for motion. Usually longer than cilia.
Pili
Aids in sexual reproduction for bacteria, transfer DNA.
Plasmids
Small circles of DNA that carry a few genes that can provide advantages, such as resistance to antibiotics.
Are plasmids in both eukaryotes and prokaryotes?
Mainly found in bacteria and naturally occur in archaea, bust also appear in some eukaryotes such as yeast and plants.
Plastids
Double-membraned organelles that function in photosynthesis, storage, and/or pigmentation .
Chloroplasts
Plastids specialized for photosynthesis [organelle of photosynthesis in the cells of plants and photosynthetic protists].
Central vacuole
Plants only. Store lots of water.
Stroma
Liquid inside the chloroplast.
Thylakoid
A flattened membrane sac inside the chloroplast, used to convert light energy into chemical energy.
Motor protein
Accessory proteins that move molecules through cells on tracks of microtubules and microfilaments. Energized by ATP.
Head function of a motor protein
Motor; site of ATP binding and hydrolysis.
Hinge function of a motor protein
Regions that bends to instigate movement.
Tail function of motor protein
Carries cargo, is attached to other proteins/binds to other components.
Cilia
Short, hairlike projections that extends from the plasma membrane and are used for locomotion. Tend to cover al or part of the surface on a cell. ONLY ON EUKARYOTES.
What kind of structure do cilia and flagella have?
9+2
Basal body
Organelle that develops from a centriole.
9+2 arrangement
Whiplike structures formed from microtubules organized in 9+2 arrays.
Microtubules come from……
Basal bodies which anchor to the cytoplasmic side of the plasma membrane.
Microtubules grow from a barrel-shaped ………?
Centriole, which remains in the cytoplasm below the basal body.
Cell cortex
Region of cytoplasm just inside the plasma membrane; often contains a mesh of microfibers and associated proteins.
Pseudopods
A temporary protrusion that helps some eukaryotic cells move and engulf prey “false feet”.
Extracellular matrix
Complete mixture of substances secreted by a cell onto its surface; composition and function vary by cell type. [acts as a glue]
Primary wall
The first cell wall of younger plant cells. They consist of lignin and cellulose.
Secondary wall
Lignin-reinforced wall that forms inside the primary wall of a mature plant cell.
Lignin
Material that strengthens cell walls of vascular plants.
Basement membrane
Extracellular matrix that attaches epithelium to underlying tissue.
Microscopy- parameters
Allows us to see very small structures- cells.
Magnification
Ratio between the size of an image produced by a microscope and its actual size.
Resolution
Ability to observe 2 adjacent objects as distinct from one another. Clarity of an image.
Contrast
How different one structure looks from another-enhanced by dyes.
What are the 2 groups of microscopy
- Light microscope
- Electron microscope
Light microscope
Uses light for illumination
Resolution .2
Electron microscope
Uses an electron beam; shorter wavelength.
Resolution 2
The… of a cell determines its structure and function
Proteome
Metabolism in cytosol
Sum of all chemical reactions by cells needed for energy.
Enzymes help accelerate these reactions.
Catabolism
[reaction type]
Breakdown of a molecule into smaller components.
Anabolism
[reaction type]
Synthesis of cellular molecules and macromolecules.
Semiautonomous organelles
Can grow and divide to reproduce themselves.
Not completely autonomous because they depend on other parts of the cell for their internal components.
Mitochondria and chloroplasts
Cisternae
Network of membranes that form flattened, fluid filled tubules.
Lumen
Internal pocket
3 different movements of motor proteins
- Move cargo from one location to another
- Motor protein can remain in place and cause the filament to move [muscle contraction]
- Motor protein and filament restricted in their movement exerts a force that causes the filament to bend [cellular movement]
Contractile vacuoles
In protists that expel excess water
Peroxisomes
Small organelle found in all eukaryotic cells.
Catalase reactions that break down toxic materials [hydrogen peroxide] by REMOVING hydrogen or ADDING oxygen.
