2.d. Levels of organisation Flashcards
When is tissue formed?
When close cells differentiate in the same way and group together
What are the three types of tissue?
- Epithelial
- Muscular
- Connective
What is the role of epithelial tissue? (2)
- To cover/line
- To protect and secrete
Epithelial cells have no blood vessels, what similar structure might they have?
Nerve endings
What is a basement membrane made of?
Collagen and protein
Where are cuboidal epithelial cells found?
- Kidney nephron
- Ducts of salivary glands
Where are columnar epithelial cells found?
In lining tubes (e.g. oviduct/trachea)
Where are squamous epithelial cells found?
- Alveoli walls
- Lining of the renal capsule of the nephron
What are the three types of muscular tissue?
- Skeletal
- Smooth
- Cardiac
What are other names used for skeletal and smooth muscle?
- Skeletal= Striped/striated
- Smooth= Unstriped/unstriated
Give 4 points about the properties of skeletal muscle
- Attached to bones
- Long cells (or fibres) give powerful contraction
- Tire easily
- Voluntary muscles
Why are skeletal muscles ‘voluntary’ muscles?
You can choose whether or not to contract the muscles
Give 4 points about the properties of smooth muscle
- Made up of individual, spindle-shaped cells
- Contract rhythmically
- Less powerful than skeletal
- Involuntary
Where is smooth muscle found? (3)
- Skin
- Blood vessel walls
- Digestive/respiratory tracts
Describe the structure of cardiac muscle in 4 points
- Never tires
- Striped
- Can modify contraction
- BUT contract rhythmically w/out stimulation
What does connective tissue do?
Connects/supports/separates tissues and organs
What does connective tissue contain?
Elastic and collagen fibres
What types of cells are inbetween fibres of connective tissue?
Adipocytes and cells of the immune system
Define ‘adipocytes’
Fat-storing cells
Define ‘organ’
A group of tissues in a structural unit, working together and performing a specific function
What are the 4 types of tissue found in the human eye?
Nervous, connective, muscle, epithelial tissue
What are the 4 types of tissue in a leaf?
Epidermal, vascular, packing (or ground) tissue
What is a leaf specialised for?
Photosynthesis
Define ‘organ system’
A group of organs working together with a particular role
Define ‘organism’
A discrete individual where all the systems of the body work together (making an organism)
