Heart Function, Blood Circulation, and Kidney Filtration
Heart Function and Blood Circulation
Phases of the Cardiac Cycle
Atrial Systole
The atria contract, pumping blood into the ventricles through the atrioventricular valves.
Ventricular Systole
The ventricles contract. Blood exits into the pulmonary artery and aorta as the semilunar valves open. Simultaneously, the atrioventricular valves close.
Diastole
The heart relaxes. Blood from the vena cavae and pulmonary veins enters the atria. Blood just pumped into the arteries cannot return to the ventricles due
Cell Biology: Characteristics, Structure, and Processes
Characteristics of Living Organisms
- Nutrition: Taking in, absorbing, and assimilating nutrients (organic substances, mineral ions) containing raw materials/energy for growth and tissue repair.
- Plants: Photosynthesis – H2O, CO2, Light
- Excretion: Removal of toxic materials and waste products of metabolism and substances in excess, produced by chemical reactions in cells (respiration).
- Respiration: Breaking down food in cells to release energy.
- Sensitivity: Sensing and responding to changes in the environment
Photosynthesis: The Core of Life on Earth
What is Photosynthesis?
Photosynthesis is the chemical process by which green plants, certain algae, and some bacteria capture light energy from the sun and convert it into chemical energy. Plants contain a green pigment called chlorophyll, located in the chloroplasts of their cells. This pigment absorbs sunlight’s energy and uses it to produce carbohydrates like glucose from water and carbon dioxide. As a byproduct, photosynthesis releases oxygen into the atmosphere, crucial for life and respiration.
Read MoreCell Biology: Structure, Function, Mitosis, and Meiosis
Cell Biology: Structure, Function, and Reproduction
Cell: The fundamental physiological, morphological, developmental, reproductive, and genetic unit of organisms.
It is the smallest unit of life.
There are two main types: prokaryotic and eukaryotic.
Prokaryotes possess a cell wall but lack a nucleus.
Eukaryotes are divided into animal and plant cells.
Animal cells, unlike plant cells, contain lysosomes that absorb lipids. Plant cells, unlike animal cells, have a cell wall made of cellulose.
Cytoplasmic
Read MoreCellular Organization: Eukaryotic vs. Prokaryotic Cells
Cellular Organization: Eukaryotic vs. Prokaryotic
Types of Cellular Organization
Eukaryotic Cell Organization: Possesses cytoplasmic compartments surrounded by membranes, producing specific chemical reactions.
Prokaryotic Cell Organization: Lacks internal compartments surrounded by membranes and a true nucleus.
Prokaryotic Cells
Plasma Membrane: The cell boundary between the cell’s interior and the external environment.
Nucleoid: The region inside the cell containing hereditary material, typically a single
Read MoreGregor Mendel: Inheritance and Genetics Pioneer
Gregor Mendel: A Biography
Early Life and Education
Born on July 22, 1822, in Heinzendorf, Austria, Gregor Mendel died on January 6, 1884, in Brno (then Brünn). In 1843, he entered the Augustinian Monastery of St. Thomas in Brno. He later studied physics, mathematics, and natural sciences in Vienna. Upon returning to the monastery, Mendel dedicated himself to investigating the variety, inheritance, and evolution of plants.
Basic Terminology of Inheritance
- Allele:
- One of two or more alternative forms