Lesson 6- Animal Form, Function, Nutrition, and Locomotion Flashcards
What is a Tissue?
groups of cells with a similar appearance and common function
What are the 4 types of tissues?
- Epithelial
- connective
- muscle
- nervous
What is an organ?
different types of tissues organized into a functional unit
What is an organ system?
a group of organs that work together provide another level of coordination and organization of a system
What is epithelial tissue (epithelia)?
- tightly packed tissue that covers outside of body and line organs and cavities in bone
- Closely packed (usually with tight junctions) which allows them to function as a barrier against mechanical injury, pathogens, fluid loss
- Form active interfaces with environment (ex: lines nasal passages for olfaction)
What are the 2 sides of epithelial tissue?
(polarized)
Apical surface (top): faces the lumen (cavity) or outside the organ, exposed to fluid or air, covered by specialized projections (ex: microvilli in small intestine to increase SA for nutrient absorption)
Basal surface (bottom)
What are the types of epithelial tissues?
- Cuboidal
- Simple Columnar
- Simple squamous
- Pseudostratified columnar
- Stratified squamous
What is cuboidal epithelium?
Dice-shaped cells specialized for secretion in kidney tubules, glands (thyroid, salivary)
What is simple columnar epithelium?
Large, brick shaped cells where active absorption or secretion occur, that line intestine to secrete digestive juices and absorb nutrients
What is simple squamous epithelium?
Platelike cells, involved in exchange of material through diffusion, thin and leaky, line blood vessels and air sacs of lungs where diffusion of nutrients and gas occurs
What is pseudostratified columnar epithelium?
- Platelike, involved in exchange of material through diffusion, thin and leaky
- lines blood vessels and air sacs of lungs where diffusion of nutrients and gas occurs
- single layer of cells varying in height, ciliated cells,
- lines respiratory tract where cilia sweep the film of mucus along the surface
What is stratified squamous epithelium?
- Multilayered, quickly regenerates (new cells form near basal lamina) replacing cells that are sloughed off
- Surfaces subject to abrasion: outer skin, linings of mouth, anus, vagina
What is connective tissue?
- Holds tissues and organs together in place
- Sparse population of cells throughout extracellular matrix (web of fibres in liquid, jelly or solid foundation)
- Matrix has fibroblasts (secrete fibre proteins) and macrophages (engulf foreign particles by phagocytosis)
What are the 3 types of fibres in connective tissue?
- Collagenous fibres: strength and flexibility (prevent skin from being pulled too far from bone)
- **Reticular fibres: **join connective and adjacent tissue (prevent skin from being pulled too far from bone)
- **Elastic fibres: **make tissues elastic (return skin to original shape after releasing grip)
What is loose connective tissue?
- Most widespread in vertebrate body, binds epithelia to underlying tissues, holds organs in place, loss weave of all 3 types of fibres
- In skin and throughout body
What is cartilage?
- Contains collagenous fibres embedded in a rubbery protein-carbohydrate complex called chondroitin sulphate
- Chondrocytes secrete collagen and chondroitin sulphate which make cartilage a strong yet flexible support material
- Skeletons of vertebrate embryos contain cartilage that is replaced by bone as the embryo matures
- In disks that act as cushions between vertebrae throughout one’s life
What is fibrous connective tissue?
- Dense with collagenous fibres
- Tendons (attach muscles to bones) and ligaments (connect bones at joints)
What is adipose tissue?
(connective tissue)
- pads and insulates body and stores fuel as fat molecules
- Each cell contains a large fat droplet that swells when fat is stored and shrinks when body uses that fat as fuel
- Stores fat in adipose cells distributed throughout its matrix
What is blood tissue?
(connective tissue)
Has liquid extracellular matrix called plasma (water, salts, dissolved proteins, erythrocytes (red blood cells- carry oxygen), leukocytes (white blood cells- defense), cell fragments (platelets- blood clotting)
What is bone tissue?
(connective tissue)
- mineralized , osteoblasts (bone-forming cells that deposit collagen matrix)
- Calcium, magnesium, phosphate ions combine into a hard mineral within the matrix
- in Skeleton of most vertebrates- structure of repeating units called osteons (concentric layers of mineralized matrix that are deposited around central canal with blood vessels and nerves)
What is muscle tissue?
- Responsible for almost all types of body movement
- Consist of filaments containing proteins actin and myosin, that enable muscles to contract
What is skeletal muscle?
(muscle tissue)
- Responsible for voluntary movements, bundles of long cells called muscle fibres
- During development fibres form by fusion of many cells, resulting in multiple nuclei in each muscle cell or fibre
- Arrangement of contractile units (sarcomeres) along fibres gives cells a striated (striped) look
- Attached to bones by tendons
- Building muscle increases size by not number of muscle fibres
What is cardiac muscle?
(muscle tissue)
- Striated like skeletal muscle and has similar contractile properties
- Has fibres that interconnect via intercalated disks (relay signals from cell to cell and help synchronize heart contraction)
- Forms contractile wall of the heart
What is smooth muscle?
(muscle tissue)
- Lacks striations, spinal shaped
- Responsible for involuntary body activities (churning of stomach and constriction of arteries)
- Found in walls of digestive tract, bladder, arteries, other internal organs
What is nervous tissue?
Receives, processes, and transmits information, a concentration of it forms the brain
What is a neuron?
(nervous tissue)
- Basic units of nervous system
- Receives nerve impulses from other neurons via cell body and multiple extensions called dendrites
- Transmit impulses to other neurons, muscles or cells through axons, which are bundled together into nerves
in brain and spinal cord
