Circulatory Systems: Open vs. Closed & Vertebrate Hearts
Circulatory Systems: Open and Closed
Two main types of circulatory systems exist: open and closed. Both share three common elements:
- A fluid (in echinoderms, it’s called hydrolymph; in most invertebrates, hemolymph; and in vertebrates, blood and lymph).
- A network of blood vessels to carry the fluid.
- A heart, a muscular organ that pumps the fluid.
Open Circulatory System
Typical of arthropods and most mollusks (except cephalopods). Blood vessels don’t form a complete network; instead, blood drains into
Read MoreUnderstanding Lipids: Types, Functions, and Classifications
Lipids: An Introduction
Lipids: They do not have a characteristic functional group but are substances of biological origin, soluble in organic solvents and insoluble in water. All lipids share a common carbohydrate-based structure, which explains their insolubility in water.
Biological Functions of Lipids
Biological functions: Lipids serve as the primary energy reserves for living organisms. They are integral components of cell membranes and play a role in regulating cellular and tissue activity.
Lipid
Read MoreHygiene and Skin Lesions
Hygiene and Cleanliness
Hygiene and cleanliness are concepts aimed at preventing disease and preserving health.
Postural Hygiene
Proper posture to avoid injuries during daily activities or work.
Occupational Hygiene
Conservation measures for health in the workplace.
The Necessity of Hygiene as Basic Health
Virginia Henderson framed hygiene within the basic needs of individuals. Maslow set physiological needs, including thermoregulation, as a priority. The skin plays an important, essential role when in
Read MorePhotosynthesis: Unveiling the Z-Scheme and Light Reactions
Photosynthesis is the process by which green plants, algae, and some bacteria convert light energy from the sun into chemical energy in the form of glucose (a type of sugar) and oxygen. This process is crucial for the sustenance of life on Earth, as it is responsible for producing the oxygen we breathe and providing the primary source of food for many organisms.
Photosynthesis takes place in the chloroplasts of plant cells, specifically in structures called thylakoids, which are disk-like membranes
Read MoreUnderstanding the Cardiovascular, Blood, and Lymphatic Systems
The Cardiovascular System
The heart is the pump that moves blood through the cardiovascular system. It consists of two halves separated by a muscular wall.
Structure of the Heart
Each half of the heart is divided into an upper and lower cavity. The heart is enclosed in the pericardium, a double sac that provides a fluid-filled space for it to beat freely.
- Myocardium: Muscle tissue that forms the heart.
- Atria: The upper chambers of the heart.
- Ventricles: The heart’s lower chambers.
- Atrioventricular Valves:
Nutrients, Digestion, and Your Body
Core Concepts in Nutrition and Digestion
Key Definitions
- Feeding: The ingestion of food selected from the environment, making up our diet.
- Food: Any substance (solid or liquid) usually ingested for living, nutritional, and psychological purposes.
- Nutrition: An involuntary process by which our body extracts the nutrients our cells need from food and transforms them into its own structures.
- Nutrients: Food substances that provide matter and energy for our cells to perform vital functions.
- Basal Metabolism: