Animal Reproduction and Development

• Regeneration occurs when some animals, such as starfish, regrow lost body parts or form new individuals from body fragments.
• Fertilization is the union of a sperm and an egg to form a zygote, which develops into a new organism.
• External fertilization happens outside the female's body, often in water, common in amphibians and fish.
• Rhizobium bacteria is a type of symbiotic bacteria found in legumes, and helps fix nitrogen in the soil, contributing to both animal digestion and reproduction.
• Ovoviviparous reproduction is a reproductive method where offspring develop inside eggs that remain inside the mother’s body until they hatch, seen in some sharks and snakes.
• Asexual reproduction occurs when an organism produces offspring without fertilization, resulting in genetically identical individuals.
• Viviparous animals give birth to live young instead of laying eggs, examples are humans, dogs, and cats.
• Sperm is the male reproductive cell responsible for fertilization.
• Oviparous animals lay eggs for reproduction, such as birds, reptiles, and most fish.
• Parthenogenesis occurs when an egg develops into an individual without fertilization and is seen in certain reptiles, insects, and fish.
• Binary fission is a form of asexual reproduction where an organism splits into two identical individuals; this is commonly seen in bacteria and protists.
• Internal fertilization occurs inside the female's body, common in mammals, birds, and reptiles.
• Egg (Ovum) is the female reproductive cell that combines with the sperm during fertilization to form a new organism.
• Sexual reproduction requires two parents and results in genetic variation in offspring.
• Budding occurs when a new organism grows out of the body of the parent, as seen in hydra and yeast.
• Sunlight is the main source of energy for plants and is used in photosynthesis.
• Chlorophyll is a green pigment that captures light energy during photosynthesis.
• Plants take in carbon dioxide from the atmosphere for photosynthesis.
• Glucose is the primary product of photosynthesis and provides energy for the plant.
• Magnesium is essential for chlorophyll production.
• Plants obtain nitrogen primarily from the soil in the form of nitrates and ammonium.
• Autotrophic nutrition describes green plants that make their own food through photosynthesis.
• Transpiration is when plants release excess water in the form of vapor.
• Nitrogen is a macronutrient required in large amounts for plant growth.
• Phosphorus is essential for strong root systems and flower formation.
• Roots absorb most of the water and minerals needed by the plant.
• Potassium helps regulate water balance and enzyme functions in plants.
• Phosphorus is a macronutrient, not a micronutrient.
• Plant roots absorb water mainly through passive absorption by osmosis.
• Legumes have Rhizobium bacteria in their root nodules, which helps fix nitrogen from the air into the soil.

Explore animal reproduction including fertilization, regeneration and asexual reproduction. Understand rhizobium bacteria's role in digestion and reproduction. Learn about viviparous, ovoviviparous, and oviparous methods, sperm and eggs.