Biology Flashcards
What is the scientific method and how is it used in biological sciences?
The scientific method is a systematic approach to answering questions and solving problems in science. It involves the formulation of a hypothesis, the design and execution of experiments or observations, the analysis of data, and the interpretation of results. In biological sciences, the scientific method is used to understand the mechanisms of life, from the molecular to the ecological level.
What are the key characteristics that distinguish living organisms from non-living ones?
Living organisms have several key characteristics that distinguish them from non-living ones, such as the ability to grow, reproduce, respond to stimuli, maintain homeostasis, and acquire and use energy.
What is the structure of DNA, and how does it code for biological information?
DNA is a double-stranded molecule that consists of nucleotides. Each nucleotide consists of a sugar, a phosphate group, and a nitrogenous base. The four nitrogenous bases are adenine, guanine, cytosine, and thymine. The sequence of these bases in DNA codes for the biological information that determines an organism’s traits.
How do different organisms acquire and process energy for their survival and growth?
Organisms acquire and process energy in different ways, depending on their metabolism. Autotrophs, such as plants, use energy from sunlight to synthesize organic compounds through photosynthesis. Heterotrophs, such as animals, obtain organic compounds by consuming other organisms or their products.
What are the mechanisms of cellular respiration and how are they regulated?
Cellular respiration is the process by which cells use oxygen and glucose to produce ATP, the energy currency of cells. It consists of three stages: glycolysis, the Krebs cycle, and oxidative phosphorylation. The process is regulated by enzymes, hormones, and feedback mechanisms.
What are the different types of cells and how do they function in different organisms?
There are two main types of cells: prokaryotic and eukaryotic. Prokaryotic cells, such as bacteria, lack a nucleus and other membrane-bound organelles. Eukaryotic cells, such as animal and plant cells, have a nucleus and other membrane-bound organelles. Different cells in different organisms have specialized functions, such as nerve cells that transmit signals, muscle cells that contract, and immune cells that defend against pathogens.
How do cells communicate with each other, and what are the signaling pathways involved?
Cells communicate with each other through a variety of signaling pathways, such as neurotransmitters, hormones, and cytokines. These pathways involve specific receptors, intracellular signaling molecules, and gene expression regulation.
What are the different levels of organization in biological systems, from molecules to ecosystems?
Biological systems can be organized into different levels of complexity, from molecules, cells, tissues, organs, organ systems, organisms, populations, communities, ecosystems, and the biosphere.
How do biological systems maintain homeostasis and respond to environmental changes?
Biological systems maintain homeostasis, a stable internal environment, through various mechanisms, such as feedback loops and regulatory systems. They also respond to environmental changes through adaptation, behavior, and evolution.
What is evolution and how does it shape the diversity of life on earth?
Evolution is the process by which species change over time through natural selection, genetic drift, and mutation. It shapes the diversity of life on earth by producing new species, adapting organisms to their environments, and promoting biodiversity.
