Human Body Science

Anatomy = the study of structure of organs and organ systems Physiology = the study of function of the organs and organ systems

• Atom • Molecule • Organelles: made up of molecules • Cells: made up of organelles • Tissue: made up of many cells with the same function • Organ: made up of multiple types of tissue • Organ System: when organs work together to perform a task • Organism: the result of all organs working together

• Epithelial • Connective • Muscular • Nervous

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• Functions: Provides protection by covering and secretes substances. • Characteristics: ➢Does NOT have it’s own blood supply ➢Dependent on diffusion of nearby capillaries for food and oxygen ➢Regenerates • Classification: Based on cell shape and number of layers Cell shape: squamous, cuboidal, or columnar Number of layers: simple (absorption, filtration, diffusion) & stratified (for areas subject to abrasion)

• Connective tissue is found throughout the body; it serves to connect different structures of the body. • Commonly has it’s own blood supply

• Bone - Cartilage - Adipose - Blood vessels

Ligaments

Produce movement and generate heat.

• Skeletal - Smooth - Cardiac

Voluntary; because it’s attached to bones.

Involuntary; found in the walls of hollow organs, intestine, blood vessels, uterus, bladder etc.

Involuntary; only found in the walls of the heart.

Cardiovascular System

It is made up of the heart, blood vessels (arteries, veins, and arterioles) and blood.

• It supports the circulation and distribution of various substances throughout the body: oxygen, hormones, and nutrients from food are some of these substances.

• Hormones released from the endocrine system influence blood pressure. • The urinary system helps regulate blood volume and pressure by adjusting urine volume. • Estrogen helps vascular health (women) • The integumentary system allows heat to escape by dilating BV’s

• The digestive system consists of all the organs from the mouth to the anus that ingest and digest food. • The organs along path include: esophagus, stomach, small and large intestine, rectum, and anus.

The digestive system manufactures enzymes that breakdown the food to release nutrients into bloodstream ⇒ Anything that is not digested is expelled through the anus ⇒ The absorption of nutrients occurs in the small intestine which consists of the duodenum, jejunum, and ileum ⇒ The colon removes water from the waste that remains. • The liver produces bile that helps break down fats, and the pancreas delivers enzymes to the small intestine that aid in digestion.

Fats are broken down by bile (produced by liver delivered through pancreas) in the stomach Carbohydrates are broken down by salivary amylase in the mouth Protein is broken down by pepsin in the small intestine

Increased skeletal muscle activity increases the motility of the gastrointestinal tract.

The endocrine system serves to control body functions through glands that secrete hormones through the blood to reach organs throughout the body.

• Glands such as the pineal, pituitary, thalamus, and hypothalamus, thyroid, thymus, and adrenal: regulate processes such as growth and metabolism. • The pancreas, testis, and ovaries also hace endocrine functions, even though they are part of other body systems.

• They lymphatic system provides a means of transportation for some hormones. • The muscular system provides protection for some endocrine glands. • The nervous system controls the secretion of hormones from the pituitary gland.