BIOL 1030 / Topic 3: Animal Anatomy and Physiology

Constitute organs, which constitute organ systems, which divides labour and improves efficiency of tasks inside the body.

• Epithelial tissue

• Muscle tissue

• Nervous tissue

• Connective tissue

Tissue covering the outside of the body and lining organs and cavities within the body.

The protein membrane.

• It protects the rest of our body from the outside world.

• It controls the movement of substances in and out through passive transport and active transport.

• It absorbs substances and secretes substances.

• Gap junctions, which are permeable structures made of protein that allow direct communication and passage of small molecules between adjacent cells.

• Tight junctions, which are impermeable structures made of protein forming a barrier between adjacent cells, preventing passage of molecules to maintain tissue integrity.

• Apical surface, which is the top surface facing the lumen (cavity outside of organ) or environment outside of body, and is thus in contact with fluid or air.

• Basolateral surface, which is the bottom and side surfaces facing the basement membrane and neighbouring cells.

• Simple epithelium, which consists of a single layer of cells, involved in processes where diffusion, absorption, and secretion occur.

• Stratified epithelium, which consists of multiple layers of cells stacked on top of each other, involved in protection for its own tissue.

• Squamous epithelium, which is flattened, having most contact for each cell with basement membrane out of all epithelia, specialized for diffusion.

• Cuboidal epithelium, which is cube-shaped, specialized for absorption and secretion of intestine.

• Columnar epithelium, which is elongated and column-shaped, specialized for sideways expansion when a cell is destroyed.

Sites of gas exchange and diffusion, such as the lungs or gills and blood vessels.

Sites of digestion and absorption, such as intestines.

Excitable tissue, having a resting (relaxed) and active (contracted) state, specialized for nearly all forms of body movement, consisting of proteins actin and myosin.

The three types of muscle tissue are: skeletal muscle, smooth muscle, and cardiac muscle.

Contraction occurs when actin and myosin slide past each other.

Actin and myosin proteins, organized in repeating bands called sarcomeres.

Single elongated cell, with a group of muscle fibres making up a muscle.

Also called striated muscle, this muscle has multiple nuclei in between muscle fibres due to fusion of fibres. This is muscle specialized for voluntary movements, and are attached to bones by connective tissues called tendons.

A huge number of sarcomeres can contract and expand, giving a large combined force that is generated for task.

Muscle specialized for involuntary body movements in vertebrates, such as tightening of arteries, and voluntary movements in invertebrates. Composed of muscle fibres but looking less compressed and lacking striations, giving the fibres a spindle-like shape.

• Circular muscular fibres.

• Longitudinal muscular fibres

There is less myosin and more actin in the smooth muscles.

Gap junctions in cardiac muscle, assisting in heart contraction synchronization and to prevent fibres to pull apart during contraction.

Only in vertebrates, muscle composed of muscle fibres interconnected via intercalated disks, responsible for being the heart contractile wall, contracting the heart.

A good indicator is the branched fibre appearance.

Nerve cells sending messages all over your body to allow you to do the things you want your body to do.

Receiving “wires” carrying electrical signals toward the cell body.

“Mini CPU” responsible for the overall functioning and regulation of the neuron and the electrical signals it receives and sends.

Shipping “wires” carrying nerve impulses away from the cell body, often bundling into the nerves.

A type of cell assisting in nourishment and insulation of neurons.

Tissue composed of neurons responsible for the receipt, processing, and shipment of electrical signals.

Neurons receive nerve impulses from other neurons through the dendrites and into its cell body, then shipping off nerve impulses to other cells like other neurons and muscle fibres via the axons.

Tissue made of a scattered population of cells in extracellular matrices, responsible for holding many tissues and organs together.

Matrix outside of the cells, composed of proteins, proteoglycans, and polysaccharides.

Connective tissue composed of dense fibres, responsible for holding a variety of tissue combinations together.

Connective tissue is composed of loose weaves of fibres binding epithelia to underlying tissue, allowing the epithelia to move freely.

It is found where stretching is important.

Specialized loose connective tissue with adipose cells called adipocytes, saving and storing fat as energy.

Each adipose cell has a fat droplet that swells when saving fat and shrinks when using fat.

Mineralized, inflexible structural connective tissue hardened through calcium and nutrients, with mineralized and inflexible extracellular matrix, to provide shape and support for body.

Cells in bones which continually break down and rebuild the extracellular matrix to maintain tissue integrity.

Strong, flexible structural connective tissue acting as a cushion, preventing bones to crush away at each other.

Connective tissue, connecting all systems of the body by transportation of oxygen, nutrients, and wastes.

• Regulator: Animal using internal mechanisms to control internal condition in the face of external changes.

• Conformer: Animal allowing internal condition to change in accordance with external changes.

• Yes, an animal can be a regulator and conformer at the same time, via regulating to specific variables and conforming to other specific variables.

The maintenance of internal balance via achieving a constant internal environment even when external environment changes significantly.

• Endotherm: Animal using internal metabolic processes as a major heat source for homeostasis.

• Ectotherm Animal using external environment as a major heat source for homeostasis.

• Poikilotherm: An animal that has a body temperature varying with environmental conditions.

• Homeotherm: An animal that has body temperature constant against environmental conditions.

• Insulation through hair, feathers, adipose, etc.

• Heat exchangers, which are vascular arrangements wherein blood vessels recapture heat from warm blood via heat transfer.

• Osmoregulator: Animal actively regulating their internal osmolarity to the external environment. E.g. vertebrate animals, both freshwater and seawater.

• Osmoconformer: Animal passively conforming their internal osmolarity to the external environment. E.g. invertebrate fishes. E.g. invertebrate animals.

• Epithelia can originate from all three embryonic germ layers – the ectoderm, the mesoderm, and the endoderm. For example, keratinocytes have an ectodermal origin, the cells that form the lining of the digestive tract develop from the endoderm, and the lining of some body cavities originate from the mesoderm.

• Muscle tissues originate from the mesodermal germ layer.

• Nervous tissues originate from the ectodermal germ layer

• Connective tissues mostly originates from the mesodermal germ layer.