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First-Year Biology

Caltech's First-Year Biology Requirement

Biology is one of the most exciting and impactful disciplines of the 21st century and at Caltech. From investigating how complex organisms develop from a single cell, to understanding the neurobiology of emotion, to recognizing the critical role microbes have played and continue to play in shaping and sustaining our planet, to coming up with new ways to control viruses, biology offers something fascinating for everyone regardless of primary major.  Indeed, some of the greatest opportunities for discovery and applications lie at the interface of biology with other disciplines. Accordingly, All Caltech students are required to take 9 units of first-year biology, which can be satisfied by taking any course numbered Bi 1. Several different course options are available, with each Bi 1 course representing a different approach to providing an introductory understanding of the biological sciences. All Bi 1 courses may be taken pass/fail if they are taken in the freshman year, independent of the term in which the course is taken. For students who are interested in the fundamentals of eukaryotic molecular and cellular biology, the freshman biology requirement can also be satisfied by completing both Bi 8 and Bi 9.

This page provides information on the different options available to students and gives guidance on how to choose the Bi 1 course that is best for you.

Bi 1 and the Core

Caltech's core curriculum is designed to provide all Caltech undergraduates with the scientific background that they need to understand the world around them and to pursue studies in any of the disciplines in which Caltech offers a degree. A basic understanding of biological principles is an integral part of a Caltech student's scientific education. Thanks to our small size and creative approach to science and instruction, we are able to teach fundamental principles of Biology in a variety of ways that tap into the interdisciplinary strengths and interests of our faculty.

Bi 1 is designed to provide insights into modern biology in a manner that provides students insights into fundamental biological mechanisms and how to understand the biological world. Core concepts such as the nature of the cell, gene expression and regulation, evolution and mutation, and energy conservation and metabolism are unique to the biological sciences and provide the starting points for understanding the biological world, with applications ranging from human health to the global environment to biotechnology.

2023-24 First-Year Biology Course Offerings

For academic year 2023-24, there are five different Bi 1 courses available.

Winter 2024

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Professor Lior Pachter

Bi 1c. Biology Through the Algorithmic Lens
9 units (3-0-6); second term. Do biological systems compute? Can we compute with biological systems? Is computer code a meaningful metaphor for genetic code? Do neural networks in biology have much to do with neural networks in computer science? In this class we will investigate these and other questions with a view towards learning about deep connections between biology and computer science that shed light on fundamental questions in biology. May be taken pass/fail if taken in a first-year student's first year. Instructor: Pachter

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Professor Ellen Rothenberg

Bi 1i. Construction and Guidance of Biological Defense
9 units (4-0-5); second term. We are bombarded by biological threats from the outside, ranging from toxic particulates to epidemic viruses, and also by threats from within, like cancer.  How do our bodies manage to be victorious against these threats for so many years, in most cases?  Many people have some familiarity with aspects of the answers now, due to COVID-19.  But how can these defense mechanisms actually work, and how can they coordinate their actions to be effective and safe?  Why do they fail?  This course will zoom between scales to introduce the cells that the body uses for immune defense and how they execute their roles, both system-wide and at the molecular level.  A central theme will be how the system is controlled by cellular "software" reading the genetic code, by ultra-rapid evolutionary mechanisms, and by elegant cell-cell communication networks.  Lectures and student presentations will be included.  May be taken pass/fail if taken in the freshman year. Limited enrollment. Given in alternate years; offered 2023-24. Instructor: Rothenberg

Spring 2024

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Professor Rob Phillips

Bi 1. The Great Ideas of Biology
9 units (4-0-5); third term. Biological processes take place at length scales ranging from that of individual protein molecules all the way to the algal blooms or rainforests that can be seen from space and over a dizzying nearly 30 orders of magnitude in time scales. This course will start by examining the biology of processes such as how plants and animals colonize oceanic islands and the physics of how animals such as wildebeest form giant herds during their year-long migration. With these wonders of the living world revealed, we will then seek to understand biological phenomena by thinking about genes and cells. May be taken pass/fail if taken in a first-year student's first year. Instructor: Phillips

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Professor Michael Dickinson

Bi 1b. The Biomechanics of Organismal Design
9 units (3-0-6); third term. Have you ever wondered how a penguin swims or why a maple seed spins to the ground? Can a flea jump as high as a kangaroo? Is spider silk really stronger than steel? This class will offer answers to these and other questions related to the mechanical design of plants and animals. The course will provide a basic introduction to how engineering principles from the fields of solid and fluid mechanics may be applied to the study of biological systems. The course emphasizes the organismal level of complexity, although topics will also connect phenomenology at the molecular, cellular, and tissue-level scales. The class is explicitly comparative in nature and will not cover medically-related biomechanics. Topics include the physical properties of biological materials, viscoelasticity, biological pumps, muscle mechanics, neural control, and animal locomotion. May be taken pass/fail if taken in the freshman year. Limited enrollment. Instructor: Dickinson

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Professor Justin Bois

Bi 1 x. The Great Ideas of Biology: Exploration through Experimentation.
9 units (0-6-3); third term. Introduction to concepts and laboratory methods in biology. Molecular biology techniques and advanced microscopy will be combined to explore the great ideas of biology: the cell, the gene, evolution by natural selection, and life as chemistry. This course is intended for nonbiology majors. May be taken pass/fail if taken in a first-year student's first year. Limited enrollment. Instructor: Bois

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