overview of basic human cells Flashcards
What are the levels of organisation?
organismal, system , organ , tissue, cellular , organelles, molecular, atomic
What are the 9 systems of the body?
integumentary, musculoskeletal, cardiovascular, respiratory, lymphatic, digestive, urinary, nervous and endocrine
What is homeostasis?
The mechanism which governs the bodies internal environment
What are the functions of epithelia?
secretion, absorption, filtration, protection and sensation
What are the 3 types of simple epithelia
simple squamous epithelia, simple cuboidal epithelia and simple columnar epithelia
What are simple epithelia?
they are always a single layer arranged in a pavement like structure , all epithelia have a basement membrane made of strong connective tissue to support them , simple epithelia DO NOT have blood vessels
What are some features functions and locations of simple squamous epithelia ?
Features = single layer, flattened, disc shaped flattened nuclei, sparse cytoplasm
Function = filtration and secretion of lubricating substances
Location = alveoli, glomeruli , lining of heart, blood & lymphatic vessels
What are some features functions and locations of simple cuboidal epithelia?
Features = cube like large cells, spherical centred nucleus, aren’t perfectly cube
Function = secretion and absorption
Location = kidney tubules , small glands, ovary surface
What are some features functions and locations of simple columnar epithelia?
Features = tall cells with oval nuclei , have cilia or microvilli and may contain goblet cells
Function = absorption / secretion
Location = digestive tract, gall bladder, ciliated ones are found in bronchi and fallopian tubes
What are stratified epithelia?
two or more layers of epithelia that regenerate from bellow, stratified epithelia are more durable , have more of a physical protection role found at the surface of cheek cells and come off when scraped as a measure of protection.
What are basal cells?
Stem cells that regenerate the stratified epithelia from bellow pushing dead or unhealthy cells upwards, this is the mechanism of epidermis replacement
What are the main types of connective tissue?
connective tissue proper, cartilage, bone, blood
What are some functions of connective tissues?
binding organs, support, protection (physical and immune), movement, storage, heat production and transport
what are the 3 main components of a connective tissue?
ground substance , cells and fibres mainly collagen and elastin
What is ground substance?
A gel like substance composed of mainly water hygroscopic proteoglycans which trap water in the connective tissues
What are the 3 types of common cells found within connective tissues?
BLAST cells, CLAST cells and CYTE cells
What are blast cells and what are some examples?
immature cells that are mitotically active and secrete ground substance as well as fibres building cells
FIBROBLASTS - connective tissue proper
CHONDROBLASTS - in cartilage
OSTEOBLASTS - in bone
What are clast cells and what are some examples?
clast cells break down connective tissue
OSTEOCLAST - in bone
CHONDROCLAST - in cartilage
What are cyte cells and what are some examples?
Often referred to as the sitting cells they are mature cells that maintain/ recycle/ breakdown ground substance
CHONDROCYTES - in cartilage
OSTEOCYTES - in bone
What are the 3 types of connective tissue proper?
Loose areolar connective tissue, dense connective tissue, adipose tissue
What is loose areolar connective tissue, where is it found, what are some functions?
Found in skin and packs around some organs. It is an elastic connective tissue containing fibroblasts, ground substance, elastin and collagen. Fibroblasts are able move through areolar tissue to repair/rebuild damaged or dying tissues.
What is dense connective tissue, where is it found, what are some functions?
There are two types, dense regular and irregular. Contains a lot of collagen fibres making it a tough and strong tissue. Regular dense tissue is found in tendons and ligaments. Irregular ones are found in deep skin tissue
Still contains ground tissue with fibroblasts between collagen fibres.
What is loose adipose connective tissue, where is it found, what are some functions?
this is a protective, cushioning tissue, children have lots of brown adipose tissue to help them keep warm and disappears as you age (brown adipose is a specialised type). General adult form contains lipids and has a rich blood & nervous supply storing fat for the body need it e.g. breast tissue
What is cartilage and what are the 3 main types?
cartilage is tough and flexible made of up to 80% water, lacks nerves and blood vessels, relies on diffusion to get rid of waste material and gain nutrients, has chondrocytes which sit inside lacuna
Three main types = hyaline cartilage, elastic cartilage, fibrocartilage.
What is hyaline cartilage and where can it be found?
This is the most abundant cartilage, pale blue in colour, surrounded by perichondrium except from around joints. Babies have hyaline cartilage which later calcifies to bone. Found in joints and bone endings.
What is elastic cartilage and where can it be found?
contains elastin and not much collagen so it is not as strong or tough as other tissues but it is more elastic. Found in ears and is yellow due to the elastin content. Lacuna contain chondroblasts.
What is fibrocartilage and where can it be found?
bundles of thick collagen fibres, doesn’t contain as much ground substance , lacuna present, very impact resistant and can act as a shock absorbent. Found between spine vertebrae to absorb shock
What are common component of all bone?
Lacunae, osteocytes, osteons, Haversian canals, periosteum, ground substance. Bone contains lots of collagen and has a central canal which contains a very rich blood and nervous supply.
What are common component of all blood?
cells, matrix, fibres , erythrocytes, lymphocytes, neutrophils, plasma
What function do glial cells have in nervous tissue?
They are able to remove excess neurotransmitters
What are the 3 main types of muscle tissue
Skeletal (voluntary), cardiac (involuntary) and smooth (involuntary)
What are the features of skeletal muscle?
multinucleated with striations, myofilaments precisely aligned to maximise power for contraction. They have a highly organised structure
What are the features of cardiac muscle?
cells branch and overlap, intercalated discs which sit between the cells as a part of them which allow electrical impulse to pass between the cells from one to the next also have striations
What are the features of smooth muscle?
Found in stomach and several other organs, no striations, mononucleate , a lot less organised
