Understanding Decision-Making, Cancer, and Health
Steps to Make a Decision
Steps to making a decision:
- Recognition of dissatisfaction with oneself.
- Decision to change or to fill a void.
- Dedication to implement the decision.
Steps to continue making a decision:
- Identify the problem.
- Recognize the problem.
- Establish parameters.
- Consider alternatives.
- Make a decision.
- Evaluate the results.
Understanding Cancer
Cancer: A group of diseases in which the body produces an excess of malignant cells (known as carcinogens or cancerous cells).
Cancer Classifications
Benign
Read MoreSkin: Structure, Functions, and Layers
The Integumentary System
The integument as an organ: The integument, also known as skin, is the body’s largest organ, accounting for 15% of body weight. The integumentary system includes the skin and its derivatives: hair, nails, and glands.
Derivatives of the Integument
- Hair: Functions include protection and sensing light touch. Hair is composed of columns of dead, keratinized cells bound together by extracellular proteins.
- Nails: Participate in grasping and handling small objects. Nails are plates
Vertebrate Animals: Fish, Amphibians, Reptiles, Birds, Mammals
Vertebrates
Vertebrates share these characteristics:
- Internal skeleton with a backbone.
- The body is usually divided into head, trunk, and tail.
- Four limbs.
- Bilateral symmetry.
- Complete digestive tube (mouth, anus) with digestive glands.
- Closed circulatory system.
- Nervous system.
- Sexual reproduction.
Fish
Habitat: Aquatic; can live in freshwater or marine environments.
Characteristics:
- Head, trunk, and tail.
- Limbs modified into fins.
- Scales.
- Swim bladder.
Vital Functions:
- Nutrition: Complete digestive system (mouth
Plant Tropisms, Nasties, and Reproductive Strategies
Types of Tropisms
Tropisms are directional growth responses of a plant to environmental stimuli.
Phototropism
Response of a plant to light variation. It is manifested by a curvature of the plant. Stems exhibit positive phototropism (growing towards light), and roots exhibit negative phototropism (growing away from light).
Hydrotropism
Response of a plant to a stimulus based on water. Roots show positive hydrotropism, growing towards water sources.
Thigmotropism
Response to stimuli from touch or physical
Read MorePhotosynthesis and Chemosynthesis in Autotrophs
Photosynthesis
All cells can obtain energy from the oxidation of organic molecules (such as glucose). Autotrophic cells must synthesize these molecules before they can catabolize them: autotrophic metabolism. The process of synthesizing biomolecules from CO2 and H2O as initial substrates, using sunlight as an energy source, is called photosynthesis.
- Overall reaction: 6CO2 + 6H2O + light → C6H12O6 + 6O2
- Photosynthetic organisms: Green plants, algae (green, red, brown), cyanobacteria, and some bacteria
Understanding the Peripheral and Central Nervous Systems
The Peripheral Nervous System
The peripheral nervous system is responsible for connecting the sensory organs and nerves with the effector organs. It consists of nerves, which are like strands formed by several axons. To prevent the passage of current, the axons are electrically isolated from each other by the myelin sheath.
The nerves are classified as:
- Sensory nerves: transmit sensory information from the sensory organs.
- Motor nerves: send commands to the effector organs.
- Mixed nerves: contain axons