Human bio term 1 Flashcards
was is the structure and function of the cytoplasm
jelly like material
fills space between nucleus and membrane
75 - 90% water
cell organelles suspended in it
regulate osmotic pressure
was is the structure and function of the nucleus
largest organelle
oval of sphere shaped
nuclear membrane: double membrane, separates nucleus from cytoplasm
nuclear pore: gaps in the nuclear membrane, lets large molecules enter and leave the nucleus
nucleolus: inside nucleus, contains genetic material in DNA, plays a part in manufacturing proteins
was is the structure and function of the ribosomes
very small spherical organelles
site of protein synthesis
either attached to endoplasmic reticulum or free floating in cytoplasm
was is the structure and function of the endoplasmic reticulum
pairs of parallel membranes extending from cell membrane to nucleus
channels are for storing or transporting molecules e.g. protein
provides surface for chemical reactions to take place
rough: ribosomes attached
smooth: no ribosomes
was is the structure and function of the Golgi body
flattened stacks
modifies and packages proteins
vesicles: small sacks of liquid containing proteins formed at the edges of the golgi body membrane
was is the structure and function of the lysosomes
small sphere containing digestive enzymes
can join with vesicles and break down material inside vesicles
remove/break down cell waste
what is the structure and function of the mitochondria
double membrane (outer and inner folded)
sausage shaped
some chemical reactions of cell respiration occur
provides energy available for cellular activities
breifly describe the cell centrioles
only appear during cell division
look like celery sticks in diagram
was is the structure and function of the cell membrane
controls/regulates movement of particles in & out of cell
regulates equilibrium in cell
phospholipid bilayer
phosphate head: hydrophilic (water loving), head faces cytoplasm and outside of cell (both mostly water)
glycerol neck connects to:
2 x fatty chain tails: hydrophobic (water hating), faces inward & not in direct contact with water
embedded between the phospholipids are proteins
list the different types of proteins embedded in the cell membrane
identity protein
receptor protein
carrier protein
channel protein
list some factors that movement across the cell membrane depends on
- concentration gradient: movement of particles from higher concentration will move to areas of lower concentration until it is evenly distributed
high - low = no energy
low - high = energy
- osmosis: diffusion of water
PASSIVE (with gradient and no energy) vs ACTIVE transport (against gradient and requires energy)
what are the different types of transport across the cell membrane
passive: no energy required
active: requires energy
explain simple diffusion
spreading out of particles from areas of high - low concentration until they’re evenly distributed down a concentration gradient
only occurs in gases and liquids
passive, no energy required
occurs across cell membrane
only lipid soluble substances
explain osmosis
movement/diffusion of water particles from areas of high to low concentration down a concentration gradient
through AQUAPORINS
water molecules can pass through both phospholipid bilayer and channel proteins.
explain the difference between facilitated diffusion and simple diffusion
facilitated: passive, with concentration gradient H-L, water soluble, requires assistance
e. g. glucose molecules
simple: passive, with concentration gradient H-L, lipid soluble, straight through membrane
e. g. O2, CO2
what are the 2 different types of passive transport
diffusion and osmosis
describe what active transport is
requires energy (ATP: adenosine triphosphate)
against concentration gradient L-H
example of active transport: vesicular transport
e.g. transporting ions
explain what vesicular transport is
movement of substances across the membrane in membranous sacks called vesicles
active process: energy is needed to form the vesicles
either
endocytosis: taking substances into the cell by vesicular transport. membrane forms around particle until completely enclosed. Vesicle pinches off and is suspended in the cytoplasm. In pinocytosis (liquids) or phagocytosis (solids)
exocytosis: contents of a vesicle inside the cell are passed to the outside. a vesicle migrates to the membrane and fuses with the membrane. contents of the vesicle are the pushed outside of the cell.
what are the 4 main types of tissue
muscular
epithelium
connective
nervous
describe the structure of epithelium tissue
cells are arranged in sheets
joined by small amount of intercellular matrix
rest on basement membrane
either:
simple epithelium: 1 layer
connective epithelium: several layers
describe the different types of simple epithelium tissue
squamous
cuboidal
columnar
ciliated
describe compound epithelium tissue
several layers of cells
cells become flatter and more scale like closer to the surface
cells lose their living contents in the skin
found in lining of mouth, pharynx and oesophagus
what is the function of epithelium tissue
lines internal organs and cavities
protects underlying cells from injury, harmful chemicals, bacteria or drying
absorption
secretes waste
sensation
describe connective tissue
binds parts of the body together
provides support
found in: rib cage, ears, and joints between bones
