[RAP0 21LAB] MIDTERM: Lesson 6 Characteristics of Life

Characteristics of Life

• To understand the fundamental characteristics of life as they apply to human anatomy and physiology.

• This discussion will explore how these characteristics define living organisms, specifically humans, and their significance in maintaining homeostasis.

• Life is defined by a set of essential characteristics that distinguish living organisms from non-living matter.

• In human anatomy and physiology, these characteristics ensure the survival, growth, and reproduction of the human body.

• Understanding these characteristics is essential for comprehending how the body functions and adapts to various internal and external changes.

  • Organization

  • Metabolism

  • Responsiveness (Irritability)

  • Movement

  • Growth

  • Differentiation

  • Reproduction

  • Homeostasis

  • Excretion

Life

It is defined by a set of essential characteristics that distinguish living organisms from non-living matter.

Organization

• The human body is highly structured, consisting of cells, tissues, organs, and organ systems.

• Each level of ___ contributes to overall function and homeostasis.

Metabolism

• The sum of all chemical reactions occurring in the body.

• Includes catabolism (breaking down substances) and anabolism (building up substances).

• Example: Cellular respiration, where glucose is broken down to release energy (ATP).

catabolism; anabolism

• Metabolism

• Includes ___ (breaking down substances) and ___ (building up substances).

Responsiveness (Irritability)

• The ability to detect and respond to stimuli.

• Example: Reflex actions, such as withdrawing a hand from a hot surface.

Movement

• Can be internal (blood circulation, digestion) or external (walking, running).

• Example: Muscle contractions enabling movement of limbs.

Growth

• Increase in size or number of cells.

• Example: Growth from infancy to adulthood, repair of tissues after injury.

Differentiation

• Process by which unspecialized cells become specialized.

• Example: Stem cells differentiating into nerve or muscle cells

Reproduction

• The formation of new cells for growth, repair, or producing offspring.

• Example: Mitosis (cell division for growth and repair) and meiosis (production of gametes for reproduction).

Homeostasis

• The ability to maintain a stable internal environment despite external changes.

• Example: Regulation of body temperature, blood glucose levels, and pH balance.

Excretion

• The process of removing waste products from metabolism.

• Example: Elimination of carbon dioxide via the respiratory system and nitrogenous wastes via the urinary system.

Negative and Positive Feedback in Homeostasis

• It is the process by which the body maintains a stable internal environment despite changes in external conditions.

• This stability is achieved through feedback mechanisms, which can be categorized as negative feedback and positive feedback.

• These mechanisms involve sensors (receptors), a control center, and effectors that help regulate physiological processes.

Homeostasis

It is the process by which the body maintains a stable internal environment despite changes in external conditions.

negative feedback; positive feedback

• Homeostasis

• This stability is achieved through feedback mechanisms, which can be categorized as ___ and ___.

receptors

• Negative feedback and positive feedback

• These mechanisms involve sensors (___), a control center, and effectors that help regulate physiological processes.

Negative Feedback Mechanism

Definition:

• A process in which the body counteracts a deviation from a set point, bringing conditions back to normal.

• Most homeostatic processes in the human body use ___ feedback.

Example:

• Regulation of Body Temperature

• Blood Glucose Regulation

counteracts a deviation

• Negative Feedback Mechanism

• Definition

• A process in which the body ___ from a set point, bringing conditions back to normal.

Regulation of Body Temperature

• Example of Negative feedback

• Stimulus: Body temperature rises above 37°C (98.6°F).

• Receptor: Thermoreceptors in the skin and hypothalamus detect the change.

• Control Center: The hypothalamus processes the information.

• Effector: The body responds by increasing sweat production and dilating blood vessels (vasodilation) to release heat.

• Result: Body temperature returns to normal.

Stimulus

• Regulation of Body Temperature

• Body temperature rises above 37°C (98.6°F).

37C (98.6F)

• Regulation of Body Temperature

• Stimulus: Body temperature rises above ___(___).

Receptor

• Regulation of Body Temperature

• Thermoreceptors in the skin and hypothalamus detect the change.

Thermoreceptors

• Regulation of Body Temperature

• Receptor: ___ in the skin and hypothalamus detect the change.

Control Center

• Regulation of Body Temperature

• The hypothalamus processes the information.

Effect

• Regulation of Body Temperature

• The body responds by increasing sweat production and dilating blood vessels (vasodilation) to release heat.

vasodilation

• Regulation of Body Temperature

• Effect: The body responds by increasing sweat production and dilating blood vessels (___) to release heat.

Result

• Regulation of Body Temperature

• Body temperature returns to normal.

Blood Glucose Regulation

• Example of Negative Feedback

• High Blood Sugar:

  • The pancreas releases insulin, which helps cells absorb glucose, reducing blood sugar levels.

• Low Blood Sugar:

  • The pancreas releases glucagon, which stimulates the liver to release stored glucose, increasing blood sugar levels.

High Blood Sugar

• Blood Glucose Regulation

• The pancreas releases insulin, which helps cells absorb glucose, reducing blood sugar levels.

insulin

• Blood Glucose Regulation

• High Blood Sugar: The pancreas releases ___, which helps cells absorb glucose, reducing blood sugar levels.

Low Blood Sugar

• Blood Glucose Regulation

• The pancreas releases glucagon, which stimulates the liver to release stored glucose, increasing blood sugar levels.

glucagon

• Blood Glucose Regulation

• Low Blood Sugar: The pancreas releases ___, which stimulates the liver to release stored glucose, increasing blood sugar levels.

Positive Feedback Mechanism

Definition:

• A process in which the body amplifies a change instead of counteracting it.

• Typically occurs in processes that need a rapid response and do not require constant regulation.

Example:

• Childbirth (Labor Contractions)

• Blood Clotting

Childbirth (Labor Contractions)

• Example of Positive Feedback

• Stimulus: Baby pushes against the cervix, causing it to stretch.

• Receptor: Stretch receptors in the cervix send signals to the brain.

• Control Center: The brain releases oxytocin, which stimulates stronger contractions.

• Effector: The uterus contracts more forcefully, pushing the baby further.

• Result: This cycle continues until the baby is delivered, after which oxytocin release stops.

Stimulus

• Childbirth (Labor Contractions)

• Baby pushes against the cervix, causing it to stretch.

Receptor

• Childbirth (Labor Contractions)

• Stretch receptors in the cervix send signals to the brain.

Control Center

• Childbirth (Labor Contractions)

• The brain releases oxytocin, which stimulates stronger contractions.

oxytocin

• Childbirth (Labor Contractions)

• The brain releases ___, which stimulates stronger contractions.

Effector

• Childbirth (Labor Contractions)

• The uterus contracts more forcefully, pushing the baby further.

Result

• Childbirth (Labor Contractions)

• This cycle continues until the baby is delivered, after which oxytocin release stops.

Blood Clotting

• Example of Positive feedback

• Stimulus: Injury to a blood vessel.

• Receptor: Platelets detect the damage and begin to adhere to the site.

• Control Center: Platelets release chemicals that attract more platelets.

• Effector: Clot formation continues until the wound is sealed.

• Result: Bleeding stops, and normal circulation resumes.

Stimulus

• Blood Clotting

• Injury to a blood vessel.

Receptor

• Blood Clotting

• Platelets detect the damage and begin to adhere to the site.

Control Center

• Blood Clotting

• Platelets release chemicals that attract more platelets.

Effector

• Blood Clotting

• Clot formation continues until the wound is sealed.

Result

• Blood Clotting

• Bleeding stops, and normal circulation resumes.

Terminology and Body Plan

• In radiologic technology, proper communication of anatomical locations and orientations is crucial.

• Understanding anatomical terminology ensures precise positioning of patients and accurate interpretation of radiographic images.

• This discussion will focus on key terminologies used in radiology and medical imaging.

  • Body Positions

  • Directional Terms

  • Body Parts and Regions

  • Anatomical Planes

  • Body Cavities

  • Serous Membranes

anatomical terminology

• Terminology and Body Plan

• Understanding ___ ensures precise positioning of patients and accurate interpretation of radiographic images.

Body Positions

• Standard Anatomical Position

• Common Radiologic Positions

Standard Anatomical Position

• Body Positions

• The body is upright, facing forward, with arms at the sides and palms facing forward.

• Feet are flat on the ground and slightly apart.

• This position serves as a reference for describing all anatomical directions and regions.

upright

• Standard Anatomical Position

• The body is ___, facing forward, with arms at the sides and palms facing forward.

Common Radiologic Positions

• Body Positions

• Supine Position

• Prone Position

• Lateral Position

• Oblique Position

• Erect Position

• Trendelenburg Position

Supine Position

• Common Radiologic Positions

• Lying on the back, face up

Prone Position

• Common Radiologic Positions

• Lying on the stomach, face down.

Lateral Position

• Common Radiologic Positions

• Lying on the side (left or right lateral decubitus).

decubitus

• Common Radiologic Positions

• Lateral Position: Lying on the side (left or right lateral ___).

Oblique Position

• Common Radiologic Positions

• Body is angled between supine and lateral positions.

Erect Position

• Common Radiologic Positions

• Standing upright (used for chest X-rays and spine imaging).

Trendelenburg Position

• Common Radiologic Positions

• Head lower than the feet (used in trauma imaging).

Directional Terms

These terms describe the location of body structures in relation to one another:

• Superior (Cranial)

• Inferior (Caudal)

• Anterior (Ventral)

• Posterior (Dorsal)

• Medial

• Lateral

• Proximal

• Distal

Superior (Cranial)

• Directional Terms

• Toward the head (e.g., the heart is ___ to the stomach).

Inferior (Caudal)

• Directional Terms

• Away from the head (e.g., the liver is ___ to the lungs).

Anterior (Ventral)

• Directional Terms

• Front side of the body (e.g., the sternum is ___ to the heart).

Posterior (Dorsal)

• Directional Terms

• Back side of the body (e.g., the spine is ___ to the stomach).

Medial

• Directional Terms

• Toward the midline (e.g., the nose is ___ to the ears).

Lateral

• Directional Terms

• Away from the midline (e.g., the arms are ___ to the chest).

Proximal

• Directional Terms

• Closer to the point of attachment (e.g., the elbow is ___ to the wrist).

Distal

• Directional Terms

• Farther from the point of attachment (e.g., the fingers are ___ to the elbow).

Body Parts and Regions

• Cephalic Region: Head

• Cervical Region: Neck

• Thoracic Region: Chest

• Abdominal Region: Stomach area

• Pelvic Region: Lower abdomen

• Upper Limb: Shoulder, arm, forearm, and hand

• Lower Limb: Thigh, leg, ankle, and foot

• Axial Region: Head, neck, and trunk

• Appendicular Region: Limbs and appendages

Cephalic Region

• Body Parts and Regions

• Head

Cervical Region

• Body Parts and Regions

• Neck

Thoracic Region

• Body Parts and Regions

• Chest

Abdominal Region

• Body Parts and Regions

• Stomach area

Pelvic Region

• Body Parts and Regions

• Lower abdomen

Upper Limb

• Body Parts and Regions

• Shoulder, arm, forearm, and hand

Lower Limb

• Body Parts and Regions

• Thigh, leg, ankle, and foot

Axial Region

• Body Parts and Regions

• Head, neck, and trunk

Appendicular Region

• Body Parts and Regions

• Limbs and appendages

Anatomical Planes

• Used in radiology to obtain specific cross-sectional images:

  • Sagittal Plane

  • Midsagittal Plane

  • Parasagittal Plane

  • Frontal (Coronal) Plane

  • Transverse (Horizontal) Plane

  • Oblique Plane

Sagittal Plane

• Anatomical Planes

• Divides the body into left and right halves.

Midsagittal Plane

• Anatomical Planes

• Equal left and right halves.

Parasagittal Plane

• Anatomical Planes

• Unequal left and right portions.

Frontal (Coronal) Plane

• Anatomical Planes

• Divides the body into anterior and posterior sections.

Transverse (Horizontal) Plane

• Anatomical Planes

• Divides the body into superior and inferior sections.

Oblique Plane

• Anatomical Planes

• Diagonal cut at an angle between horizontal and vertical planes.

Body Cavities

These cavities house and protect internal organs:

• Dorsal Cavity (posterior side)

  • Cranial Cavity

  • Vertebral (Spinal) Cavity

• Ventral Cavity (anterior side)

  • Thoracic Cavity

  • Abdominopelvic Cavity

    • Abdominal Cavity

    • Pelvic Cavity

Dorsal Cavity

• Body Cavities

• Posterior side

  • Cranial Cavity

  • Vertebral (Spinal) Cavity

Cranial Cavity

• Dorsal Cavity

• Contains the brain.

Vertebral (Spinal) Cavity

• Dorsal Cavity

• Contains the spinal cord.

Ventral Cavity

• Body Cavities

• Anterior side

  • Thoracic Cavity

  • Abdominopelvic Cavity

    • Abdominal Cavity

    • Pelvic Cavity

Thoracic Cavity

• Ventral Cavity

• Contains the heart and lungs.

Abdominopelvic Cavity

• Ventral Cavity

  • Abdominal Cavity

  • Pelvic Cavity

Abdominal Cavity

• Abdominopelvic Cavity

• Contains digestive organs (stomach, liver, intestines).

Pelvic Cavity

• Abdominopelvic Cavity

• Contains reproductive and excretory organs.

Serous Membranes

• It line body cavities and cover organs, reducing friction during movement.

  • Pleura

  • Pericardium

  • Peritoneum

Pleura

• Serous Membranes

• Surrounds the lungs (visceral ___ covers lungs; parietal ___ lines the thoracic cavity).

Pericardium

• Serous Membranes

• Surrounds the heart (visceral ___ covers heart; parietal ___ lines heart cavity).

Peritoneum

• Serous Membranes

• Surrounds the abdominal organs (visceral ___ covers organs; parietal ___ lines abdominal cavity).