Life Sciences Prepared By: Ma’am Justine Life Sciences • Life Sciences are the branches of science that study living things. A student who studies the life sciences would be learning more about plants, animals, human beings or even tiny microscopic organisms. Biology is the foundation of the life sciences. It’s defined as the study of life and how living things survive and change. Because biology covers so many aspects important to life, many scientists consider biology and life sciences to synonymous terms. Below are some fields in the life sciences: • • • • • • • Anatomy/Anthropology Astrobiology Biochemistry Botany Microbiology Toxicology Zoology • Anatomy/Anthropology • Anatomy and anthropology are two distinct disciplines that focus on different aspects of the human body and human society. Here's a brief explanation of the difference between the two: • Anatomy is the branch of science that deals with the structure and organization of the human body. It involves studying the various systems, organs, and tissues of the body, their functions, and how they are interconnected. • Anthropology is a social science that encompasses the study of human beings, their societies, cultures, and behaviors. It seeks to understand the diverse aspects of human existence, including their social, cultural, linguistic, and biological dimensions. • Astrobiology • Astrobiology is the study of life in the universe. The search for life beyond the Earth requires an understanding of life, and the nature of the environments that support it, as well as planetary, planetary system and stellar interactions and processes. • Biochemistry • Biochemistry explores chemical processes related to living organisms. It is a laboratory-based science combining biology and chemistry. • Botany • “Botany is the branch of Biology that deals with the study of plants.” The term 'botany' is derived from an adjective 'botanic' that is again derived from the Greek word 'botane'. One who studies 'botany' is known as a 'botanist'. Botany is one of the world's oldest natural sciences. • Microbiology •Microbiology is the study of the biology of microscopic organisms viruses, bacteria, algae, fungi, slime molds, and protozoa. • Toxicology •Toxicology is the study of how natural or man-made poisons cause undesirable effects in living organisms. • Zoology • Zoology is the study of all animals of all shapes and sizes, from tiny insects to large mammals. Zoologists investigate what animals eat and how they live, and how animals interact with their habitats. Lesson 1: The Beginning of Life How Life Began? o The universe is about 4.6 billion years old. The formation of the Earth along with other planets of our solar system is believed to have occurred some 4.5 billion years ago. Life on Earth, however, probably began only between 3.5 and 4.0 billion years ago. The important question is how was life first formed? Evidence from fossil records show that the oldest fossil resembled the onecelled organism like bacteria. Life on Earth – A Timeline 5 to 4.6 Billion Years Ago Origin of the earth from a swirling disk of gas, dust and debris surrounding the infant sun. 4 to 3.7 Billion Years Ago Life begins! Scientists believe it didn’t take long after the infant Earth cooled from a molten, asteroid bombarded hell for microbes to start spreading. Chemical evidence suggests life had originated before 3.7 billion years ago. No one knows exactly when it happened, or how it happened, but scientists have devised some plausible scenarios by which complex molecules organized themselves into something like DNA which could start evolving through natural selection. About 1.2 Billion Years Ago First multi-celled organisms are thought to have appeared. Around the same time, sex was invented. 415-375 Million Years Ago Invasion of the land! First plants colonized the continents, the insects, and then, with all that good stuff up there to eat, vertebrates. The fish best equipped for the journey to land were species with muscular fins that had come in handy for crawling around the bottoms of swamps. 250 MILLION YEARS AGO Continents unite to form Pangea. A mass extinction takes place wiping out 95% of all species that had inhabited the Earth. 230 MILLION YEARS AGO Age of dinosaurs begins. 200 MILLION YEARS AGO Giant continent begins to break apart. 65 MILLION YEARS AGO Age of dinosaurs abruptly ends. Many scientists believed they died in a mass extinction precipitated by an asteroid impact and subsequent climate change. What they don't know is why dinosaurs died and not early alligators, turtles, and mammals survived. Some descendants of dinosaurs still survive: birds. 28 MILLION YEARS AGO Apes appear 8-6 MILLION YEARS AGO Human lineage diverges from that of our closet living relatives. chimpanzees. THANK YOU!!