Intro to Biology for Nursing Students

• Lecture 1 is an introduction to biology for nursing students studying Biology, Biophysics, and Biochemistry in 2023-2024, taught by Prof. Laura Pacini.
• All files provided are copyrighted and cannot be reproduced.

Biology Syllabus Overview

• Cell Theory forms the basic unit of life
• Discussion of Prokaryotic and Eukaryotic cells
• The chemistry of life and includes eukaryotic cellular compartments and intracellular organelles, such as: Plasma membrane, Cytoplasm, Ribosomes, Smooth and Rough Endoplasmic Reticulum, Golgi apparatus, Lysosomes, Peroxisomes, and the Cytoskeleton.
• Includes the nuclear compartment, molecular basis of hereditary information, RNA structure and function, and protein synthesis.

Recommended Textbook

• Biology, 13th Edition, McGraw Hill by Peter Raven, George Johnson, Kenneth Mason, Jonathan Losos and Tod Duncan.

Introduction to Biology: Key Questions

• Biology is the scientific study of Life.
• What characteristics defines life?
• What makes something alive?

Characteristics of Living Organisms

• Living organisms are highly organized compared to natural inanimate objects and are made of cells.
• Living organisms reproduce themselves.
• Living organisms are based on a universal Genetic Code which grows and develops.
• Living organisms display homeostasis, maintaining a relatively constant internal environment.
• Living organisms respond to stimuli.
• Living organisms take energy and matter from the environment and transform it.
• Living organisms show adaptation to their environment (Evolution).

Life's Organization

• Biology studies life at levels from molecular and cellular to ecosystems and the biosphere.
• Living systems exhibit hierarchical organization.

Levels of Biological Organization

• Cellular Level: Atoms, molecules, organelles, cells; the cell is the basic unit of life.
• Organismal Level: Tissues, organs, organ systems.
• Populational Level: Population and community.
• Ecosystem Level.
• Biosphere: The Earth is an ecosystem also known as the Biosphere.

Reproduction in Living Organisms

• All living things reproduce, creating new, similar organisms.
• Asexual reproduction involves a single cell producing offspring identical to itself.
• Sexual reproduction involves cells from two parents uniting to form the first cell of a new organism.

Growth and Development

• GROWTH involves an increase in size and mass.
• In a single-celled organism, growth is mainly an increase in size.
• Multicellular organisms grow in size and cell number.
• DEVELOPMENT involves transformation during the life of an organism.

Homeostasis

• Living organisms display homeostasis.

Response to Stimuli

• All living things detect and respond to environmental stimuli.
• A stimulus is a signal that triggers a response in an organism.

Energy

• Metabolism: The sum of chemical reactions that in living cells provide energy.
• The energy is used to grow and reproduce, to build and maintain their structures ,and to respond to their environment.
• Cellular Respiration and Photosynthesis.

Universal Molecules

• Living organisms are composed of similar molecules that participate in the same chemical reactions.
• Metabolism encompasses all chemical reactions necessary to sustain a living organism.
• Cells function as biochemical factories that uses the same basic molecular building blocks.
• The source of atoms (food/matter) and source of energy is required for activity.

Importance of Cell Biology

• Understanding cell biology is important to understand the basis of disease.
• Diseases can mainly be explained by a dysfunction at the cellular level.
• Examples of diseases caused by cellular dysfunction include: Hypercholesterolemia, Cystic Fibrosis, Hypertension, Muscular dystrophy and Cancer.

Relevance of Biology to Medicine

• Crucial for medical students for understanding cell structure.
• Crucial for medical students for understanding Pharmacology, Disease Mechanisms, Genetics, Microbiology, & Immunology.
• Crucial for medical students for understanding Research and Technological Innovation, Diagnosis and Treatment and Ethical Considerations.

Universal Features of Cells

• All living things are made of cells, small membrane-enclosed units filled with a concentrated aqueous solution of chemicals.
• All living things have the ability to replicate by growing and dividing in two.

Unity and Diversity of Life

• Organisms on Earth show great diversity in form and function.
• Despite diversity, all organisms share characteristics differentiating them from non-living things.
• The diversity lies in appearance, size, shape, chemical requirement, and function; cells are fundamentally similar inside.

Tree of Life

• The Tree of Life has three primary branches: Bacteria, Archaea, and Eukaryotes.

Prokaryotes vs. Eukaryotes

• Prokaryotes lack a nucleus or other membrane-enclosed compartments and distinct organelles (Bacteria, Archaea).
• Eukaryotes have a membrane-enclosed nucleus and other membrane-enclosed compartments or organelles (Animals, Plants, Fungi, Protists).