7: Animal Tissues Flashcards
What are the tasks of body parts?
- Coordinate and control individual parts
- Acquire and distribute raw materials to cells and dispose of wastes
- Protect tissues against injury or attack
- Maintain the internal environment (homeostasis)
What are the four cell junctions?
- Tight junctions - so close that are sometimes impermeable, prevents fluid from seeping between epithelial cells
- Adhering junctions - transmembrane linker proteins, hold cells together at distinct spots
- Desmosomes - anchoring junctions, where filaments anchor to the opposite side
- Gap junctions - Permits ions and small molecules to pass from cytoplasm of one cell to another
Explain epithelial tissues
- A sheet of cells that covers the body’s outer surface and lines its internal ducts and cavities
- As protection, sensory reception, formation of slippery surfaces for movement and filtration
What are the descriptions of epithelial tissues?
- Thickness:
Simple epithelium - one cell thick
Stratified epithelium - more than one cell thick - Cell shape:
Squamous - thin, flattened, wider than tall
Cuboidal - cube-shaped, as tall as wide
Columnar - column-shaped, taller than wide
What is the glandular epithelium?
Organs that release substances onto the skin, or into a body cavity or interstitial fluid
What is the exocrine gland?
- Glands with ducts
- Unicellular (goblet cell scattered within the epithelial lining of intestines, produces mucin)
- Multicellular (epithelium-walled duct)
What are the types of mucus secreting glands?
- mammary glands - milk
- sweat glands
- oil glands
- salivary gland
- liver - bile
- pancreas - digestive enzymes
What are endocrine glands?
- Ductless glands which secretes hormones into extracellular space to enter the blood and travel to specific target organs
What are the major endocrine glands?
- pituitary gland
- pineal gland
- thyroid gland
- adrenal gland
- pancreas
- ovary/testis
What are connective tissues?
- Consists of cells and the extracellular matrix they secrete
- Functions to connect body parts and provide structural and functional support to other body tissues
What are soft connective tissues?
- Has dispersed cells, more extracellular material and extensive protein fibers in the extracellular matrix
- loose connective tissue - fibroblasts secrete a matrix of complex carbohydrates with fibers dispersed widely through the matrix
- dense connective tissue (collagen fibers) - dense irregular: supports skin/internal organs
dense regular: ligaments and tendons
What are specialised connective tissues?
Cartilage: rubbery extracellular matrix, supports and cushions bones
Adipose tissue: fat filled cells, stores energy, cushions and protects organs
Blood: connects the body systems, contains erythrocytes, leukocytes and platelets suspended in plasma
Bone: rigid support, muscle attachment, protection, mineral storage and blood production
Explain blood
- blood cells are made in red marrow near the ends of long bones by a process called haemopoiesis
- leukocytes: wbc that functions in defense against viruses, bacteria and other invaders
- platelets: a cell fragment that aids in blood clotting
- erythrocytes: rbc that transports oxygen
What is muscle tissue?
- made up of cells that contract when simulated and requires ATP energy
What are the three types of muscle tissues?
- Skeletal muscle tissue - moves the skeleton voluntarily and is a long, striated cell with many nuclei
- Cardiac muscle tissue - heart muscle (involuntary) and is striated with a single nuclei
- Smooth muscle tissue - in walls of hollow organs (involuntary) and no striations, only a single nuclei
