Life Cycle of Plants: Sexual & Asexual Reproduction
Life Cycle of Plants
Sexual Reproduction
Plants are formed from the union of two specialized cells called gametes during fertilization to create a zygote.
Advantages:
- Genetic diversity through recombination.
- Different genotypes in each generation.
Asexual Reproduction
New plants develop from one or more cells of a progenitor plant.
Disadvantage:
- Produces clones with identical genotypes to the parent.
Advantage:
- Faster reproduction requiring only one individual.
- Effective colonization.
Haploid and Diploid Phases
Haploid
Read MoreViruses, Cellular Structures, and Processes
Viruses
Viruses originate in aquatic environments and can associate with particular ways of life. They are free, evolving entities that survive by becoming parasites. Essentially, they are organisms that have lost their cellular machinery through adaptation to parasitism or are genetic fragments detached from cellular organisms. Their specificity lies in their nucleic acid, which allows them to parasitize cells.
Each virion consists of a nucleic acid (DNA or RNA, never both simultaneously), a capsid
Read MoreHuman Biology: A Comprehensive Overview of Organ Systems
Human Biology
Circulatory System
Arteries
Structure: Arteries have thick, slightly elastic walls to withstand high pressure from the heart’s pumping action.
Function: Arteries carry oxygenated, nutrient-rich blood away from the heart. Muscle contractions in artery walls regulate blood flow to organs.
Veins
Structure: Veins have thinner walls and one-way valves to prevent backflow.
Function: Veins return deoxygenated blood carrying cellular waste to the heart. Muscle contractions also control blood volume.
Read MorePrimate Classification and Characteristics
Classification of Primates
Primates belong to the class of mammals and are divided into:
Prosimians
Retain some characteristics of insectivorous mammals. These include the lemurs of Madagascar, lorises, and tarsiers.
Apes
Characterized by exploratory activity and liveliness. They have a complex social life based on sharp colors on the head, buttocks, and fur. Well-developed facial muscles allow them to express their emotions. Their vocal communication includes signs. Examples include New World monkeys
Read MoreThe Musculoskeletal System: Bones, Muscles, and Joints
The Musculoskeletal System
Bones
Bones are the main components of the skeleton. They are strong, hard, and tough organs composed of bone tissue, a specialized connective tissue with calcified extracellular components.
Chemical Composition:
- 25% H2O
- 45% mineral
- 30% organic matter
Functions of Bone:
The musculoskeletal system causes the skeleton to serve as the structural framework of the body. It protects vital organs, allows movement, and is a deposit of hematopoietic organs. Bone marrow houses and forms
Read MoreIntroduction to Cell Biology and Genetics
Cell Theory
The cell is the smallest form of life and the basic unit of all living organisms. Every cell in a living being originates from another existing cell. Information necessary for the life of cells is passed from one generation to the next.
Chromosome Theory of Heredity
A gene, located on a DNA fragment, carries the information for a particular character. Genes are aligned one after another on chromosomes. Each gene occupies a specific location (loci) on a chromosome. Each character is located
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