Unifying Themes of Biology PDF

1.2 Unifying Themes of Biology KEY CONCEPT Unifying themes connect concepts from many fields of biology. 1.2 Unifying Themes of Biology All levels of life have systems of related parts. A system is an organized group of interacting parts. – A cell is a system of chemicals...

1.2 Unifying Themes of Biology KEY CONCEPT Unifying themes connect concepts from many fields of biology. 1.2 Unifying Themes of Biology All levels of life have systems of related parts. A system is an organized group of interacting parts. – A cell is a system of chemicals and processes. – A body system includes organs that interact. 1.2 Unifying Themes of Biology All levels of life have systems of related parts. An ecosystem includes living and nonliving things that interact. An ecosystem is composed of three primary components. These consist of living organisms and their material remains, also referred to as organic or ​biotic factors​; their physical environment, which includes rocks and minerals, sunlight, atmosphere, water and other non-organic ​abiotic factors​; and the interrelationships between them within a given area. 1.2 Unifying Themes of Biology Structure and function are related in biology. One of the unifying themes of Biology is that structure determines function; how something is arranged allows it to perform a specific job. Structure determines function. – Proteins with different structures perform different functions. – Heart muscle cells have a different structure and function than stomach muscle cells. – Different species have different anatomical structures with different functions. 1.2 Unifying Themes of Biology The shape (structure) of a protein determines its function. For example, there are two basic shapes for proteins: fibrous and globular (round). Fibrous proteins, such as collagen are shaped like a rope and give strength to our skin to prevent it from tearing. Fibrous proteins are structural proteins because they help give shape to and support the skin. Globular proteins, such as hemoglobin, are used to transport oxygen in the blood. 1.2 Unifying Themes of Biology Organisms must maintain homeostasis to survive in diverse environments. Homeostasis is the maintenance of constant internal conditions. 1.2 Unifying Themes of Biology Homeostasis is the maintenance of constant internal conditions. – Homeostasis is usually maintained through negative feedback. 1.2 Unifying Themes of Biology Behaviors and adaptations can help maintain homeostasis. Polar bear hair shafts are actually hollow, which allows the fur to reflect back the light of the sun. Much like ice, this reflection is what allows these bears to appear white or even yellow at times. 1.2 Unifying Themes of Biology Behaviors and adaptations can help maintain homeostasis. ▪ long neck, which allows it to reach food high up in trees ▪ strong legs, which enable it to run fast and escape predators ▪ and its long eyelashes, which protect its eyes from dust and dirt. 1.2 Unifying Themes of Biology Behaviors and adaptations can help maintain homeostasis. ▪ A peacock’s most obvious adaptation is its long tail. ▪ The male uses his long, brightly colored tail to attract a mate. Cactus have thorns to trap air, collect water, provide shade, and keep predators at a distance. 1.2 Unifying Themes of Biology Evolution explains the unity and diversity of life. Evolution is the change in living things over time. – The genetic makeup of a population of a species changes. – Evolution can occur through natural selection of adaptations. – Adaptations are beneficial inherited traits that are passed to future generations. 1.2 Unifying Themes of Biology Evolution explains the unity and diversity of life. Evolution is the change in living things over time. – The genetic makeup of a population of a species changes. – Evolution can occur through natural selection of adaptations. 1.2 Unifying Themes of Biology Evolution explains the unity and diversity of life. Evolution is the change in living things over time. – The genetic makeup of a population of a species changes. – Evolution can occur through natural selection of adaptations. 1.2 Unifying Themes of Biology All levels of life have systems of related parts A system is an organized group of interacting parts. – A cell is a system of chemicals and processes. – A body system includes organs that interact. – An ecosystem includes living and nonliving things that interact. 1.2 Unifying Themes of Biology Biology and Society Knowledge from biological science can be applied to specific problems in the society to improve human life.