Lecture 4 cells and tissues Flashcards
Cell structure (3 parts)
plasma membrane
nucleus
cytoplasm- cytosol (ICF) + organelles
Plasma membrane structure
Fluid mosaic model
lipid bi layer - phospholipids & cholesterol (unsaturated & saturated tails)
Membrane proteins
Carbohydrate group
Membrane proteins
trans-membrane proteins
integral proteins
peripheral proteins
Carbohydrate group
attached externally to proteins or phospholipids
ex: glycoprotein or glycolipid
Functions of the PM
boundary between ICF and ECF
selectively permeable and transport
cellular communication
structural support
Name the basic types of membrane proteins
Transport proteins (channels, carriers, pumps)
Receptors
Enzymes
Structural proteins
Channels
Ions pass this way
filled with water
passive
quantenary in structure
Carriers
binds to molecule and moves it across membrane
no open to both sides at same time
passive
Pumps
Active transport
moves against gradient
requires energy
EX: sodium potassium pump
Receptors
receive chemical signals
EX: acetylcholine receptors/neuromuscular junction
Enzymes
catalyst
speed up chemical reactions
most are proteins
EX: adenylyl cyclase
Structural proteins
support and anchor cells
cell junctions
EX: integrin
Nuclear envelope
double membrane
pores to allow communication w/ the cytoplasm
passageway for mRNA
Nucleolus
contains proteins and DNA
controls synthesis of rRNA
Chromatin
loosely packed DNA and proteins
condenses into chromosomes during cell division
Cytoskeleton:
MICROFILAMENTS
network just inside of cell membrane
composed of actin
Cytoskeleton:
Microtubules
largest cytoskeleton fiber
made of tubulin
have cilia and flagella
vesicle transport
Centrioles
made from microtubules
direct DNA movement during cell division
assemble microtubules
form mitotic spindle
Ribosomes
synthesis of proteins
composed of rRNA and protein
subunits ( 1 large, 1 small)
assembles protein chain
Rough ER
continuation of outer nuclear membrane
ribosomes on outer membrane
site of protein synthesis (membrane and secretory proteins)
Smooth ER
lacks ribosomes
synthesis lipids
concentrates and store calcium ions Ca2+
Golgi apparatus
consists of cisternae
surrounded by vesicles
protein modification and packaging
Mitochondria
double membrane
2 separate compartments
site of most ATP synthesis in the cell
Where ETC is, aerobic respiration (requires oxygen)
inter membrane space and inner membrane which contains matrix
Lysosomes
storage vesicles
contain powerful digestive enzymes
role in programmed cell death
Peroxisomes
contain enzymes that break down fatty acids and some foreign materials
produces hydrogen dioxide
contain catalyst that breaks down hydrogen peroxide
Tight Junctions
prevent movement and leakage between cells
Anchoring junction
anchor cells to one another
withstand pulling and stretching
EX: epidermis and cardiac muscle
Gap Junctions
creates cytoplasmic bridges between adjacent cells
ion channel allow for communication
EX: cardiac muscle
Exchange
functional type
simple squamous epithelial
alveoli of lungs
endothelium
Transporting
FT
simple cuboidal and simple columnar epithelial
requires a lot of ATP so it needs more cytoplasm
small intestines
renal tubules
Ciliated
FT
pseudostratified and simple ciliated columnar epithelial
Trachea
uterine tube
Protective
FT
stratified squamous epithelial and transitional epithelial
skin
esophagus
bladder
Secretory
FT
glandular
exocrine and endocine glands
Characteristics of connective tissue
cells scattered in extracellular matrix
vascular
diversity of subtypes
components of connective tissue
cells (fibroblasts, adipocytes, defense cells, tissue specific types)
extracellular matrix = ground substance + protein fibers (collagen, elastic, etc)
loose connective tissues
areolar CT, adipose tissue, reticular CT
Dense connective tissue
dense regular CT
dense irregular CT
elastic CT
other types of connective tissue
besides loose and dense
blood and lymph
cartilage (3 types)
bone tissue
Nervous tissue
cells
functions
neurons- functional cells of the nervous system excitable cells - produce electrical signals (action potentials) functions: communicate, control and integration glial cells (neuroglia) - supporting cells
skeletal muscle
striated
voluntary
cardiac muscle
striated
involuntary
smooth muscle
non-striated
involuntary
properties of muscular tissue
contractile - produce force and movement
excitable
elastic
