Cells Flashcards
- Sites of ribosome assembly
- Dense non-membranous mass where RNA is synthesized
- Location for the components found in ribosomes
Nucleolus
Most cells are composed of four elements:
Carbon Hydrogen Oxygen Nitrogen
- Scattered throughout the nucleus and present when the cell is not dividing
- Condenses to form dense, rodlike bodies called chromosomes when the cell divides
Chromatin
3 main regions of cells
C, N, P
- Cytoplasm
- Nucleus
- Plasma membrane
The Plasma Membrane is also called
plasmalemma
needed for building proteins and necessary for cell reproduction
DNA
The activity of an organism depends on the _____ of its cells
collective activities
“water loving” polar “heads” are oriented on the inner and outer surfaces of the membrane
Hydrophilic
- Contains cell contents
- Separates cell contents from the environment
- forms the outer boundary of the cell
The Plasma Membrane
is the basic structural and functional unit of living organisms
cell
3 regions of Nucleus: CNN
- Nuclear envelope (membrane)
- Nucleolus
- Chromatin
___ and ___ scattered among the phospholipids; it determines the fluidity of the plasma membrane
Cholesterol and proteins
the model that is constructed of 2 layers of phospholipids arranged “tail to tail”
Fluid mosaic model
- Control center of the cell
* Site where the genetic material is stored
Nucleus
“water-fearing” nonpolar “tails” form the center (interior) of the membrane
Makes the plasma membrane relatively impermeable to most water-soluble molecules
Hydrophobic
Nuclear envelope encloses the jellylike fluid
nucleoplasm
Selective impermeable to maintains the ____
homeostasis
• Fluid mosaic model is constructed of _____ arranged “tail to tail”
2 layers of phospholipids
- Separates the nucleus from the cytoplasm
- Consists of a double membrane that bounds the nucleus
- Contains nucleopores which are a potential passageway for the exchange of substances
Nuclear envelope (membrane)
Classification of proteins that act as transporters or receptors.
Peripheral proteins
Responsible for specialized membrane functions: ERT
o Enzymes
o Receptors for hormones or other chemical messengers
o Transport as channels or carriers
Depending on Protein position it can be classified as:
Pp, Ip
Peripheral proteins
Integral proteins
Classification of proteins that act as cytoskeleton anchors or enzymes
Integral proteins
made ribosome
Protein
The Carbohydrates consist of _____ and _____ which form a glycocalyx
glycolipids and glycoproteins
filmy covering is
glycocalyx
- The cellular material outside the nucleus and inside the plasma membrane
- The portion of the cell located between the plasma membrane and the nucleus
- Site of most cellular activities
Cytoplasm
are branched sugars attached to proteins that abut the extracellular space
Glycoproteins
is the fuzzy, sticky, sugar-rich area on the cell’s surface
Glycocalyx
3 major components of the Cytoplasm (CIO)
Cytosol
Inclusions
Organelles
Chemical substances that float in the cytosol
Inclusions
The fluid that suspends other elements and contains nutrients and electrolytes
Cytosol
Metabolic machinery of the cell that performs functions for the cell
Organelles
folds created by the inner membrane
cristae
inside the mitochondria created by the inner membrane
matrix
- “Powerhouses” of the cell
* Responsible for the ATP production via cell respiration
Mitochondria
• Sites of protein synthesis in the cell
Ribosomes
Ribosomes can be found at two locations:
free-floating in cytoplasm
part of RER
- Fluid-filled tunnels (or canals) that carry substances within the cell
- Continuous with the nuclear membrane
Endoplasmic reticulum (ER)
Two types of Endoplasmic Reticulum:
- Rough endoplasmic reticulum
* Smooth endoplasmic reticulum
In RER,
• _____ is attached
• ____ vesicles move proteins within the cell
Ribosomes
Transport
arrange order:
1 - Protein is packaged in a tiny membranous sac transport vesicle
2 - As the protein synthesize at the ribosome, it migrates to the RER tunnel system.
3- The transport vesicle buds from the RER and travels to the golgi apparatus for processing
4 - In the tunnel, the protein folds into its functional shape. Short sugar chains may be attached to the protein that forms glycoprotein
2, 4, 1, 3
- Modifies and packages proteins arriving from the rough ER via transport vesicles
- Produces different types of packages
Golgi apparatus
Protein assembly
Transport vesicles move proteins within cell
RER
In SER,
• ____ ribosomes
• Functions in ______
lacks
lipid metabolism
Detoxification and Lipid production
SER
Golgi apparatus different types of packages (SIL)
o Secretory vesicles (pathway 1)
o In-house proteins and lipids (pathway 2)
o Lysosomes (pathway 3)
• Membranous sacs of oxidase enzymes
Peroxisomes
cell drinking
Pinocytosis
- Membranous “bags” that contain digestive enzymes
* House phagocytes that dispose of bacteria and cell debris
Lysosomes
- Network of protein structures that extend throughout the cytoplasm
- Provides the cell with an internal framework that determines cell shape, supports organelles, and provides the machinery for intracellular transport
Cytoskeleton
cell eating
Phagocytes
3 different types of elements form the cytoskeleton: MIM
Microfilaments
Intermediate filaments
Microtubules
the middle type of element of the cytoskeleton
form purple network surrounding pink nucleus
Intermediate filaments
Cytoskeleton provides the cell with an ______ that determines cell shape, supports organelles, and provides the machinery for intracellular transport
internal framework
- Generate microtubules
* Direct the formation of mitotic spindle during cell division
Centrioles
the largest type of element of the cytoskeleton
form blue batlike network
Microfilaments
the smallest type of element of the cytoskeleton
appear as gold networks surrounding cell pink nucleus
Microtubules
move materials across the cell surface
Cilia
propel the cell and speeding up the sperm
Flagella
are tiny, fingerlike extensions of the plasma membrane
Strengthen the surface area that is needed for absorption
Microvilli
red blood cell
Erythrocyte
Cilia are located in the respiratory system(lungs) to move _________
mucus
platelets
Thrombocytes
white blood cells
Leukocytes
Carries oxygen in the bloodstream
Erythrocyte (red blood cell)
Secretes cable-like fibers
Fibroblast
Cells responsible for moving organs and body parts
Skeletal muscle and smooth muscle cells
Cells that cover and line body organs
Epithelial cell
Cells that stores nutrients
Fat cells
Cell that fights disease
Leukocytes (wbc)
Cell that gathers information and controls body functions
Nerve cell (neuron)
- Largest cell in the body
* Divides to become an embryo upon fertilization
Oocyte (female)
- Built for swimming to the egg for fertilization
* Flagellum acts as a motile whip
Sperm (male)
Where does fertilization occur?
fallopian tube then to uterus
What if it stays in the fallopian tube?
Abnormality, ectopic pregnancy.
• Homogeneous mixture of two or more components
Solution
dissolving
present in the larger quantity
Solvent
components in smaller quantities within a solution
being dissolve
Solutes
the body’s main solvent is ______
water
- Inside the cell
* Solution containing gases, nutrients, and salts dissolved in water
Intracellular fluid
- Outside the cell
- Fluid on the exterior of the cell
- Contains thousands of ingredients, such as nutrients, hormones, neurotransmitters, salts, waste products
Extracellular fluid (interstitial fluid)
2 basic methods of transport (PA)
Passive processes
Active processes
move across the membrane
no need metabolic energy
Passive processes
the cell provides the metabolic energy (ATP) to drive the transport process
needs ATP
Active processes
- movement is from high concentration to low concentration
* Movement of solute
Diffusion
- An unassisted process
* Solutes are lipid-soluble or small enough to pass through membrane pores
Simple diffusion
• Movement of water
Osmosis
same solute and water concentrations
Isotonic
contain more solutes than the cells do
(cell shrinking)
Lesser solute
Hypertonic
contain fewer solutes
(cell bursting)
Greater solute, Lesser water
Hypotonic
• Transports lipid-insoluble and large substances
Facilitated diffusion
High to low but pressure is involved.
• A pressure gradient must exist that pushes solute-containing fluid (filtrate) from a high-pressure area to a lower-pressure area
Filtration
Diffusion movement of _______
Osmosis movement of ________
Filtration ____
solute
solvent
pressure
- ATP is used to move substances across a membrane
* Low to high
Active processes
ATP energizes _____
solute pumps
Active transport example: SP
sodium-potassium
transported out of the cell
extracellular fluid ECF
Sodium
transported into the cell
intracellular ICF
Potassium
PISO means
Potassium inside; Sodium Outside
Where sodium goes, ____
water follows
substances are moved across the membrane “in bulk” without actually crossing the plasma membrane
Vesicular transport
out the cell
Mechanism cells use to actively secrete hormones, mucus, and other products
Exocytosis
in the cell
Extracellular substances are enclosed (engulfed) in a membranous vesicle
Everything happens inside the cell
Endocytosis
Types of endocytosis PPR
- Phagocytosis
- Pinocytosis
- Receptor-mediated endocytosis
“cell eating”
a protective mechanism, not a means of getting nutrients
Phagocytosis
“cell drinking”
Cell “gulps” droplets of extracellular fluid containing dissolved proteins or fats
Pinocytosis
Receptor proteins on the membrane surface bind only certain substances
Receptor-mediated endocytosis