Lecture 4 and 5 Flashcards
What are the general functions of cells in the human body
- Covering
- Lining
- Storage
- Movement
- Connection
- Defence
- Communication
- Reproduction
Describe covering
Protect outer surface of the body
Describe lining
Regulate nutrient movement into body tissues
Describe storage
Store lipid reserves
Store carbohydrate nutrients as glycogen
Describe movement
Pump blood
Move skeleton
Describe connection
Form ligaments that attach bone to bone
Describe defence
Produce antibodies to target antigens or invading cells
Describe communication
Send information between regions of the brain
Describe reproduction
Produce new blood cells
Produce new invididual
Characteristics of the plasma membrane
Regulates the passage of
gases, nutrients, and wastes between the internal and external
environments of the cell
Has lipids and proteins
Characteristics of the cytoplasm
• All materials (solid and liquid) between plasma membrane and nucleus • Cytosol • Inclusions • Organelles
Characteristics of the nucleus
contains genetic information (DNA)
• controls the shape and activity through protein synthesis
• exports genetic information as RNA via the nucleolus
Describe the contents of a prototypical cell
A generalised cell(not a real cell in the body)
Combines features from many different cells for teaching purposes
Describe the structure of the plasma membrane
Composed of a bilayer of phospholipids with their hydrophobic, fatty acid tails in contact with each other
Integral proteins embedded in the phosoplipid bilayer
Peripheral proteins on the inner or outer surface of the phospholipid bilayer
Carbohydrates attached to proteins or lipids on the extracellular side of the membrane
Cholesterol tucked between the hydrophobic tails of the membrane phospholipids
What are the 3 parts of the cytoplasm
Cytosol
Inclusions
Organelles
Describe cytosol
• A viscous, syrup-like fluid containing many different dissolved substances such as: • Ions • Nutrients • Proteins • Carbohydrates • Amino acids
Describe inclusions
Large storage aggregates of complex molecules found in the
cytosol
Examples: melanin, glyocgen
Describe organelles
Little organs
• A type of division of labor
• The type and number of organelles within a cell is a reflection of the cell’s
function
Structure of endoplasmic reticulum
• A network of intracellular
membrane-bound tunnels
Structure of rough endoplasmic reticulum
• Walls appear rough due to attachment of ribosomes on outside of the RER membrane
Structure of smooth endoplasmic reticulum
Walls have a smooth appearance (no ribosomes!)
• Continuous with RER
Structure of Golgi apparatus
• Stacked cisternae whose lateral edges bulge, pinch off, and give rise to small transport and secretory vesicles
Structure of lysosomes
Lysosomes are vesicles generated
by the Golgi apparatus
Structure of peroxisomes
Vesicles smaller than lysosomes
Structure of mitochondria
• Bean-shaped organelles with double membrane
Structure of ribosomes
Comprised of a large and small
subunit
Structure of centrosome
a pair of centrioles at right angles to
each other
Structure of centrioles
nine sets of microtubule triplets
Structure of cilia
Cell surface extensions that
contain microfilaments
capable of movement
Structure of flagella
often single extension that
contain microfilaments
capable of movement
Structure of microvilli
‘finger-like’ extensions of the
cell surface. Non-motile
Function of rough endoplasmic reticulum
functions to synthesise, transport, or store proteins for: • Secretion by the cell • Incorporation into the plasma membrane • Creation of lysosomes
Function of smooth endoplasmic reticulum
- Functions include:
- Synthesis, transport, and storage of lipids including steroid hormones
- Metabolism of carbohydrates
- Detoxification of drugs, alcohol, and poisons
Function of Golgi apparatus
• Function to receive proteins and lipids from the RER for modification, sorting, and
packaging
Function of lysosomes
Contain enzymes used to digest
(breakdown) and remove waste
products and damaged organelles
within the cell (autophagy)
Function of peroxisomes
• Use O2 and an enzyme
(catalase) to detoxify harmful
molecules taken into the cell
Function of mitochondria
Function to produce a high energy containing molecule called ATP on the cristae
Function of ribosomes
• Responsible for protein synthesis
Function of cytoskeleton
• Provides the structural
component of the cell
• Helps moves organelles and
materials through the cell
Function of centrosome and centrioles
involved in organizing
microtubules
• attached to chromosomes during
cell division causing chromosomal
migration
Function of cilia
to move phlegm and other
substances
Function of flagella
to propel/move cells
Function of microvilli
to increase surface area
Describe contents of the nucleus
• Contains DNA
• Control centre for cellular activity
Chromatin coils to form chromosomes
DNA unwound into chromatin
Functions of the nucleus
Houses genetic material which directs all cellular activities and regulates cellular structure
Produces ribosomal subunits in nucleolus and exports them into cytoplasm for assembly into ribosomes
List the four major tissue types in the body
- epithelial tissue
- connective tissue
- muscle tissue
- nervous tissue
Examples of • epithelial tissue
Simple squamous
Simple cuboidal
Simple columnar
Pseudostratified
Examples of • connective tissue
adipose tissue, cartilage, bone, blood, and lymph
Examples of • muscle tissue
Skeletal muscle
Smooth muscle
Cardiac muscle
Examples of • nervous tissue
Found in brain, spinal cord and nerves
Structure of simple squamous epithelium
• Single layer of flat cells
Structure of simple cuboidal epithelium
• Single layer of cube-shaped cells
Structure of simple columnar epithelium with microvilli
Single layer of cells that are taller than they are wide
Structure of Simple columnar ciliated epithelium
Some epithelial cells possess cilia on
their apical surface (respiratory and
reproductive systems
Structure of Stratified squamous epithelium
• Multiple layers of flattened cells
Structure of Stratified cuboidal epithelium
Multiple layers of cube-shaped cells
Structure of Stratified Columnar Epithelium
Multiple layers of cells that
are taller than they are wide
Structure of Pseudostratified Columnar
Epithelium
• Single layer of columnar epithelial cells but layered appearance of nuclei suggest
multiple layers of cells
Structure of transitional epithelium
• Found lining the inside of the urinary bladder
Describe squamous epithelium
Squamous epithelial cells are flat and sheet-like in appearance.
Describe cuboidal epithelium
Cuboidal epithelial cells are cube-like in appearance, meaning they have equal width, height and depth.
Describe columnar epithelium
Columnar epithelial cells are column-like in appearance, meaning they are taller than they are wide.
Describe simple epithelium
A simple epithelium means that there’s only one layer of cells.
Describe stratified epithelium
A stratified epithelium is made up of more than one layer of cells.
Describe pseudostratified epithelium
A pseudostratified epithelium is made up of closely packed cells that appear to be arranged in layers because they’re different sizes, but there’s actually just one layer of cells.
Functions of epithelia tissue
Physical protection
• Selective permeability
Secretions
Sensations
Explain physical protection
from dehydration and abrasion; and
physical, chemical, and biological agents
Explain selective permeability
–regulates the passage of certain
molecules in or out of a certain region of the body
Explain secretions
some epithelial cells called exocrine cells
produce secretions such as sweat or oil
Explain sensations
–possess nerve endings that can detect light,
taste, sound, smell, and hearing
Where is simple squamous epithelium found
lines blood vessels and body cavities
Where is Simple cuboidal epithelium found
found in glandular (secreting) tissue and kidney tubules.
Where is Simple columnar epithelium found
line your stomach and intestines.
Where is Stratified squamous epithelium found
Lines the esophagus, mouth, and vagina
Where is Stratified cuboidal epithelium found
found in the excretory ducts of your salivary and sweat glands.
Where is Stratified columnar epithelium found
lining your eyelids
Where is Pseudostratified columnar epithelium found
lines your upper respiratory tract
Structure of connective tissue
Ground substance Protein fibres(elastic fibres, collagen fibres, reticular fibres) Mesenchymal cell Blood vessel Macrophage Adipocyte Fibroblast
Functions of connective tissue
- Physical protection
- Support and structural framework
- Binding of structures
- Storage
- Transport
- Immune protection
3 Classification of connective tissue
CT proper
• Supporting CT
• Fluid CT
Connective tissue proper 2 different categories
Loose CT
Dense CT
Loose CT
has fewer protein fibres and more ground
substance
Dense CT
has more protein fibres and less ground
substance
3 different types of loose connective tissue
Areolar
Adipose
Reticular
3 different types of dense connective tissue
Regular
Irregular
Elastic
Supporting connective tissue 2 different categories
Cartilage(Semisolid matrix)
Bone(Solid matrix)
3 different types of cartilage
Hyaline
Fibrocartilage
Elastic
3 different types of bone
Compact bone
Spongy bone
Fluid connective tissue components
Plasma
Erythrocytes
Leukocytes
Platelets
Describe plasma
a watery ground substance containing protein fibres
Describe Erythrocytes
red blood cells
Describe Leukocytes
white blood cells
Describe Platelets
fragments of blood cells involved in blood clotting
Where is loose connective tissue found
surrounding kidney
Stroma of spleen
Surround nerves
Where is dense connective tissue found
Tendons and ligaments
Dermis
Walls of large arteries
Structure of mucous membrane
line the body cavities and hollow passageways that open to the external environment, and include the digestive, respiratory, excretory, and reproductive tracts
Structure of serous membranes
is an epithelial membrane composed of mesodermally derived epithelium called the mesothelium that is supported by connective tissue
Structure of cutaneous membranes
a stratified squamous epithelial membrane resting on top of connective tissue
Structure of synovial membranes
composed of well-vascularised areolar, fibrous or adipose connective
tissue
Function of mucous membranes
to protect the body from harmful external agents
Function of serous membranes
secrete a lubricating fluid which reduces friction from movements
Function of cutaneous membranes
protects body from external environment and prevents water loss
Function of synovial membranes
secretes Synovial fluid - reduces joint friction & provides nutrients to the
joint surfaces