Exercise 4 Flashcards
List the four major types of tissues in the human body
The four major types of tissues in the human body are
i) connective tissue ii) muscular tissue iii) nervous tissue iv) epithelial tissue.
How is connective tissue categorized? State the function of each type of connective tissue and give examples.
Connective tissue is categorized into three types:
i) Fibrous connective tissue includes loose fibrous connective tissue (adipose tissue) and dense fibrous connective tissue. It binds and protects organs, stores fat (adipose tissue) and forms the structural framework (ligaments and tendons) ii) Support connective tissue includes cartilage and bone. It supports, protects and moves the body. iii) Fluid Connective tissue includes blood and lymph derived from blood. It transports and fights infection.
What is muscular tissue formed of? What are the three types of muscle tissue, and describe each in terms of striations and whether they function voluntarily or involuntarily?
Muscular tissue is formed of cells called muscle fibres. The three types of muscles are as follows:
i) skeletal muscle – voluntary and striated cells ii) smooth muscle – involuntary and no striations to the cell iii) cardiac muscle – involuntary and striated cells
What is the other name given to nerve cells? Where is nerve tissue found, what is it composed of and what is its main function?
Nerve cells are also called neurons. Nerve tissue is found in the brain and spinal cord and is composed of neurons (nerve cell) and neuroglia (support cell). Individual nerves (axon fibres bound by connective tissue) are found throughout the body. The main function of the nervous system is to transmit information throughout the body.
Describe the structure and function of epithelial tissue and how it is classified.
Epithelial tissue also referred to as epithelium is made up of tightly packed cells that form a continuous layer. The function of epithelium is to cover surfaces and to line body cavities providing protection but it may also secrete, absorb, excrete or filtrate. Epithelial tissue is named according to the shape of the cell and is divided into two categories:
i) simple epithelia (single layer of cells) – squamous (lines lungs and blood vessels) -cuboidal (lines kidney and various glands) -columnar (lines digestive tract and oviducts) ii) stratified epithelia (layers of cells) – line nose, mouth, esophagus, anal canal and vagina
When is epithelium, considered a gland? What are the two categories of glands?
Epithelium is considered a gland when it secretes a product. There are two types of glands, exocrine glands which secrete their products into ducts and endocrine glands which secrete their products into the blood stream.
List the 12 organ systems of the body and briefly state what each does. (Note: The Lymphatic and Immune Systems are considered separate systems although they share organs.)
Integumentary System -Skin and accessory organs such as nails and hair. Covers and protects the body and maintains body temperature
Cardiovascular System – Blood containing nutrients, hormones and oxygen is pumped into blood vessels that carry blood to all the cells of the body and then removes cellular wastes.
Lymphatic and Immune System – Lymphatic vessels absorb fat from the digestive system and collect excess tissue fluid returning it to the blood within veins of CV system. This system is also involved in immunity as it protects the body from disease through the production of antibodies.
Digestive System – receives food and digests it into nutrient molecules which can be absorbed from the system into the blood and transported to the cells of the body. Also rids body of non-digestible food.
Respiratory System – brings oxygen into the body and allows for the exit of carbon dioxide out of the body.
Urinary System – rids the body of nitrogenous and other wastes and helps regulate the fluid level and chemical composition of blood.
Skeletal System – protects and supports body parts and allows for movement by providing a place for the muscular system to attach to.
Muscular System – protects and supports body parts and allows for movement through contraction and produces heat that maintains body temperature.
Nervous System – Conducts nerve impulses originating from both the internal and external environments regulating and coordinating the activities of all the other systems.
Endocrine System – contains glands that produce hormones that act as chemical messengers that communicate between all the systems of the body to help maintain balance.
Reproductive System – carries out functions that allow humans to reproduce.
Name the two main cavities that the body is divided into. What are the two parts in each of these cavities and the organs that are found in each part?
i) Ventral Cavity – Thoracic cavity – lungs and heart
Abdominal cavity – stomach, liver, spleen, gallbladder small and large intestines, rectum, urinary bladder and reproductive organs
(diaphragm separates the thoracic and abdominal cavities)
ii) Dorsal Cavity – Cranial cavity – brain
Vertebral canal – vertebra and spinal cord
List the four major types of membranes, where they are found and their purpose.
Body membranes line cavities and the internal spaces of organs and tubes that open to the outside. They are formed of one or more types of tissue. The four types of membranes are:
i) mucous membranes - line tubes of the digestive, respiratory, urinary and reproductive systems acting to protect them from viruses and bacteria, and in the case of the stomach, from acid.
ii) serous membranes - line the thoracic and abdominal cavities and the organs found within them, acting to support the internal organs and compartmentalize the thoracic and abdominal cavities. Examples are pleura, pericardium and peritoneum.
iii) synovial membranes - line the cavities of freely movable joints, secreting synovial fluid into the joint cavity allowing free movement.
iv) meninges - are membranes found within the dorsal cavity providing a protective covering for the brain and spinal cord
Define homeostasis
Homeostasis refers to the relative constancy of the body’s internal environment. It refers to the body‘s need to remain in balance no matter what is happening internally or externally.
What are the two fluids involved in maintaining homeostasis?
The two fluids involved in maintaining homeostasis are blood and tissue fluid. Blood delivers oxygen and nutrients to the tissues and carries away carbon dioxide and waste products. Tissue fluid bathes all the cells of the body and is the medium through which substances are exchanged between cells and the blood. Body systems must work together to ensure that these substances remain in a normal range.
What is a tissue? What is an organ? What is an organ system?
A tissue is composed of specialized cells of the same type that perform a common function in the body.
An organ contains several types of tissues working together to do a specific job.
An organ system contains several organs working together for a common purpose.
