Biology: Cell Structure and Functions

Cellular Biology

• The human cell is considered the basic unit of structure.
• Protoplasm is a colorless, jelly-like substance that contains proteins, fats, carbohydrates, mineral salts, and water.
• The principal parts of a cell are the cytoplasm, nucleus, and cell membrane.

Cellular Differentiation

• Differentiation is the process of specialization of cells through repeated division during early development stages.

Cellular Metabolism

• Anabolism is the process of building up larger molecules from smaller ones.

Tissue Types

• Ectodermal (outer) layer cells form glands of the skin, linings of the mouth, anal canal, epidermis, hair, nails, and nervous system.
• Perichondrium is a membrane that covers cartilage.
• Nervous tissue initiates, controls, and coordinates the body's adaptation to its surroundings.
• Adipose tissue is areolar tissue with an abundance of fat-containing cells.

Body Orientation and Structure

• The coronal plane divides the body into front and back.
• Dorsal cavities contain cranial and spinal cavities.
• The shoulder joint is located in the deltoid region.

Skin Structure and Functions

• Stratum spinosum varies in thickness and consists of irregularly shaped cells containing melanin.
• Stratum germinativum is the deepest layer of the epidermis.
• Pavilion corpuscles are egg-shaped receptors found throughout the subcutaneous layer, sensitive to vibration and pressure.
• Healthy skin has a slightly acidic pH balance.

Skin Functions and Disorders

• Eccrine glands secrete a fluid composed mostly of water and some bodily wastes.
• Arrector pili muscles cause goose bumps.
• A cyst is a closed, abnormally developed sac containing pus, semifluid, or morbid matter above or below the skin.
• A wheal is an itchy, swollen lesion caused by a blow, scratch, insect bite, or skin allergy.
• An excoriation is a skin sore or abrasion produced by scratching or scraping.
• A scale is a thin, dry or oily plate of epidermal flakes.
• Rosacea is associated with excessive oiliness of the skin and chronic inflammation of the cheeks and nose.

Bone Structure and Functions

• Basal cell carcinomas are the most common and least malignant type of skin cancer.
• Long bones, such as legs, arms, fingers, and toes, have compact bone forming their shafts and the outside of flat bones.
• Inside long bones, calcaneus bone consists of irregularly shaped spaces defined by thin bony plates called trabeculae.
• The thoracic cage consists of ribs and sternum.
• The patella is also known as the knee cap.

Joints and Movement

• Synarthrotic joints are functionally or essentially immobile.
• The ball and socket joint allows the greatest range of motion and movement through all planes of the body.
• Osteoarthritis is a chronic disease that accompanies aging, eroding articular cartilage and resulting in abnormal bone thickening and progressive joint immobility.

Muscle Functions and Structure

• Muscle movement is responsible for locomotion, breathing, moving fluids, and transporting goods through the digestive system.
• The skeletal muscular system consists of over 600 large and small muscles.
• Irritability refers to the capacity of muscles to receive and react to stimuli.
• The sarcoplasmic reticulum is a network of membranous channels within the muscle cell that release calcium ions, causing muscle contractions.
• Aerobic cellular respiration takes place in the mitochondria of the muscle cell.

Cellular Biology

• The human cell is considered the basic unit of structure.
• Protoplasm is a colorless, jelly-like substance that contains proteins, fats, carbohydrates, mineral salts, and water.
• The principal parts of a cell are the cytoplasm, nucleus, and cell membrane.

Cellular Differentiation

• Differentiation is the process of specialization of cells through repeated division during early development stages.

Cellular Metabolism

• Anabolism is the process of building up larger molecules from smaller ones.

Tissue Types

• Ectodermal (outer) layer cells form glands of the skin, linings of the mouth, anal canal, epidermis, hair, nails, and nervous system.
• Perichondrium is a membrane that covers cartilage.
• Nervous tissue initiates, controls, and coordinates the body's adaptation to its surroundings.
• Adipose tissue is areolar tissue with an abundance of fat-containing cells.

Body Orientation and Structure

• The coronal plane divides the body into front and back.
• Dorsal cavities contain cranial and spinal cavities.
• The shoulder joint is located in the deltoid region.

Skin Structure and Functions

• Stratum spinosum varies in thickness and consists of irregularly shaped cells containing melanin.
• Stratum germinativum is the deepest layer of the epidermis.
• Pavilion corpuscles are egg-shaped receptors found throughout the subcutaneous layer, sensitive to vibration and pressure.
• Healthy skin has a slightly acidic pH balance.

Skin Functions and Disorders

• Eccrine glands secrete a fluid composed mostly of water and some bodily wastes.
• Arrector pili muscles cause goose bumps.
• A cyst is a closed, abnormally developed sac containing pus, semifluid, or morbid matter above or below the skin.
• A wheal is an itchy, swollen lesion caused by a blow, scratch, insect bite, or skin allergy.
• An excoriation is a skin sore or abrasion produced by scratching or scraping.
• A scale is a thin, dry or oily plate of epidermal flakes.
• Rosacea is associated with excessive oiliness of the skin and chronic inflammation of the cheeks and nose.

Bone Structure and Functions

• Basal cell carcinomas are the most common and least malignant type of skin cancer.
• Long bones, such as legs, arms, fingers, and toes, have compact bone forming their shafts and the outside of flat bones.
• Inside long bones, calcaneus bone consists of irregularly shaped spaces defined by thin bony plates called trabeculae.
• The thoracic cage consists of ribs and sternum.
• The patella is also known as the knee cap.

Joints and Movement

• Synarthrotic joints are functionally or essentially immobile.
• The ball and socket joint allows the greatest range of motion and movement through all planes of the body.
• Osteoarthritis is a chronic disease that accompanies aging, eroding articular cartilage and resulting in abnormal bone thickening and progressive joint immobility.

Muscle Functions and Structure

• Muscle movement is responsible for locomotion, breathing, moving fluids, and transporting goods through the digestive system.
• The skeletal muscular system consists of over 600 large and small muscles.
• Irritability refers to the capacity of muscles to receive and react to stimuli.
• The sarcoplasmic reticulum is a network of membranous channels within the muscle cell that release calcium ions, causing muscle contractions.
• Aerobic cellular respiration takes place in the mitochondria of the muscle cell.