Day 5 Body Structure
In order to understand the evolution of complexity in organisms we will spend some time talking about body structure
Lets learn the parts...
Animal Body Structures
Tissue
Animal tissues are classified into 4 types
-Epithelial
-Connective
-Muscle
-Nervous
-Epithelial Tissue is basically any tissue that covers something or lines something
-Ex: Skin or stomach lining
-Connective Tissue supports and binds things together
-There are four major types of connective tissue
-Adipose Tissue - a type of loose connective tissue that stores lipids. Known as fat
-Cartilage - A hard yet flexible tissue used for support
-Like human ears or the whole skeleton of a shark
-Bone Cells - Made of calcium phosphate and calcium carbonate making it very hard
-Blood - a connective tissue in which fluid called plasma suspends special cells (blood cells)
-Muscle Tissue allows movement
-There are three kinds of muscle tissue
-Skeletal muscles are the ones associated with movement
-Smooth muscle has a turning motion. It is the type that moves food around and expands the bladder
-Cardiac muscles cause the heart beat
-Nervous tissue is for communication
-There are lots of types
-Neurons - Impulse conducting
-Neuroglia - Protection, support, and nourishment
-Peripheral glial cells - Form sheaths to protect the peripheral nervous system
Organ systems
Integumentary system
Skin, hair, nails
Nervous system
Brain, spinal cord, nerves
Endocrine system
Hormone-secreting glands (pituitary, thyroid, adrenals)
Skeletal system
Bones, cartilages
Muscular system
Skeletal muscles
Circulatory system
Heart, blood vessels, lymphatic vessels
Immune system
Bone marrow, lymphoid organs
Respiratory system
Lungs, Airways
Urinary system
Kidneys, ureters, urethra
Digestive system
Mouth, stomach, intestine, liver, gallbladder, pancreas
Reproductive system
Gonads, external genitalia, associated glans and ducts
Assignment:
Sign up for an organ system. Once you pick your system you need to pick an animal. By yourself or with your partner you are going to draw and diagram that system in that animal in your sketchbook. You will also describe how that system works in that animal. You need to explain what each organ in that system does. Everyone in your group needs to have the work in their sketchbook. You will present to the class together as a group next week. You cannot have the same animal as anyone else, including the other classes. This is worth 25 points.
Body symmetry
Animals come in three different types of symmetry
-Asymmetry - Has no symmetry like sea sponges
-Bilateral symmetry - The animals can be divided into right and left mirror images like humans
-Radial symmetry - The animal can be divided in anyway along the aboral oral axis and make a mirror image like sea jellies
Terms of direction
When doing dissections or describing animals we use terms of directions. Sometimes animals do not have heads, a mouth, a front, or a back, so describing them can be difficult without knowing the terms of direction.
Aboral - The end opposite the mouth
Oral - The end containing the mouth
Anterior - The head end
Posterior - The tail end
Caudal - Toward the tail
Cephalic - Toward the head
Distal - Away from the point of attachment (Toes are distal to the knee)
Proximal - Toward the point of attachment (The hip is proximal to the knee)
Dorsal - The back of an animal
Ventral - The belly or underside of an animal
Inferior - Below a point
Superior - Above a point
Lateral - Away from the plane that divides a bilateral animal into a mirror image
Medial (Median) - On or near the plane that divides a bilateral animal into a mirror image
Assignment:
Draw or print a picture of an animal, any animal, and in your sketchbook draw with arrows and circles these terms of direction:
Aboral - The end opposite the mouth
Oral - The end containing the mouth
Anterior - The head end
Posterior - The tail end
Caudal - Toward the tail
Cephalic - Toward the head
Dorsal - The back of an animal
Ventral - The belly or underside of an animal