Lec Test 1 CH4 Flashcards
What are the smallest “the functional unit of the body”
cell
Three main structural features of a cell
Plasma membrane, nucleus, cytoplasm
the cell membrane that forms the outer, limiting barrier separating the internal contents of the cell from the external environment
Plasma membrane
the largest structure within the cell and is enclosed by a nuclear envelope
Nucleus
a general term for all cellular contents located between the plasma membrane and the nucleus
Cytoplasm
The fluid within the nucleus is called
nucleoplasm
Modified extensions of the plasma membrane include
cilia, a flagellum, and microvilli
The three primary components of the cytoplasm are
cytosol, organelles, and inclusions
Organelles enclosed by a membrane similar to the cell membrane
Membrane bound organelles
5 membrane-bound organelles
endoplasmic reticulum (rough and smooth), Golgi apparatus, lysosomes, peroxisomes, and mitochondria
Organelles not enclosed within a membrane, generally composed of protein
Non-membrane bound organelles
4 non-membrane bound organelles
ribosomes (either fixed to a membrane or free within the cytosol), the cytoskeleton, the centrosome, and proteasomes
clusters of a single type of molecule
Inclusions
complex organized structures with unique shapes and functions
organelles
Forms the outer, limiting barrier of the cell separating the contents of the cell from the external environment
plasma membrane
hairlike projections extending from cell membrane, move mucus and substances along the surface of tissue (eg mucus in throat)
Cilia
similar to cilia but longer, propel cells, only present in humans in sperm
Flagellum
small extensions of the cell membrane, increase surface area of tissue for nutrient absorption, eg in small intestine
Microvilli
part of the cell contains the genetic material, DNA
Nucleus
different name for cytosol
Intracellular fluid or cytoplasmic matrix
3 general functions cells perform
Maintain the integrity and shape of the cell, obtain nutrients and form chemical building blocks, dispose of wastes
type of lipid forms the plasma membrane
Phospholipids
type of protein is embedded within and extends across lipid bilayer
Integral proteins
type of protein is attached loosely to surfaces of the membrane
Peripheral proteins
6 types of proteins
Transport, receptor, identity, enzyme, anchoring site, cell-adhesion
regulate movement of substances across the plasma membrane, eg channels, carriers, pumps, symporters, antiporters
Transport protein
bind to ligands which bind to macromolecules like neurotransmitters
Receptor protein
communicate to other cells that they belong in the body, eg tagging by immune cells
Identity marker
attached to either internal or external surface of cell, catalyzes chemical reactions
Enzyme
secure cytoskeleton to plasma membrane
Anchoring site
for cell-to-cell attachments (membrane junctions)
Cell-adhesion
Movement of substance from high to low concentration of solute
diffusion
Channel mediated or carrier mediated diffusion that moves charged or polar solutes through the plasma membrane that would otherwise be blocked
facilitated diffusion
Passive movement of water through a selectively permeable membrane
osmosis
the ability of a solution to change the volume or pressure of a cell by osmosis
Tonicity
lower concentration of solutes than cytosol, water moves from outside cell to inside cell
Hypotonicity
higher concentration of solutes than cytosol, water moves from inside the cell to outside
Hypertonicity
the means by which large substances or large amounts of substances are secreted from a cell
Exocytosis
the mean by which large substances or large amounts of substances are taken up by a cell
Endocytosis
cellular eating, a cell engulfs a large particle external to the cell
phagocytosis
cellular drinking, a cell internalizes droplets of interstitial fluid
pinocytosis
uses receptor proteins to bring molecules in the interstitial fluid into the cell
receptor-mediated endocytosis
A plasma membrane that allows the passage of water, but its phospholipid bylayer blocks most solutes
selectively permeable membrane
movemement against a concentration gradient
Active transport
movement with a concentration gradient
passive transport
Involves energy input to move large substances across the plasma membrane by a vesicle, a membrane-bound sac filled with substances
vesicular transport
How osmosis effects cell
cell gains or loses water through osmosis based on tonicity of cell
One of the most important tonic solutions in the body
blood
cell shrinkage due to loss of water in a hypertonic solution
Crenation
ruptured red blood cells
Hemolysis
to rupture
lysis
a membrane bound sac filled with materials
Vesicle
active transport process that use ATP to move ions across the cell membrane
Ion pumps
active transport process that requires energy to transport vesicles
Vesicular transport
divided into rough and smooth; synthesizes proteins, lipids, and vesicles
endoplasmic reticulum
ER that has ribosomes and synthesizes proteins
Rough ER
ER that has no ribosomes and synthesizes lipids
Smooth ER
organelle that makes vesicles
Golgi apparatus
organelles eat unneeded substances inside the cell
Lysosomes
organelles that detoxify the cell and create hydrogen peroxide
Peroxisomes
organelle that creates ATP, engage in aerobic respiration
Mitochondria
adenosine triphosphate, cellular energy
ATP
organelle that synthesizes proteins
Ribosomes
type of ribosome bound to rough ER, synthesize protein
Bound ribosomes
type of ribosomes that moves around in the cytosol, synthesize protein
Free ribosomes
structural support of the cell
Cytoskeleton
organelle that guides cell divisions
Centrosome
organelle that has membrane with openings and DNA and a nucleolus
Nucleus
the nucleus of the nucleus
Nucleolus
the membrane of the nucleus
Nuclear membrane
cell division in somatic cells, all cells except sex cells
Mitosis
cell division that occurs in sex cells
Meiosis
Digest proteins that are damaged, incorrectly folded, or no longer needed, controls quality of exported cell proteins
proteasomes
Which cells do not have a nucleus
Red blood cells
