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1 Nov 2017
K. Selph, OCN 201 Fall 2017 1
Science of the Sea - Biology Karen Selph Department of Oceanography School of Ocean and Earth Sciences and Technology
Science of the Sea ! Between 1 – 10 million species of plants and animals live in
the Ocean ! The ocean has the greatest diversity of plants, animals and
microbial groups on Earth
! Study of Marine Life - ! Marine Biology
! Scientific study of organisms that live in the marine environment
! Marine Ecology ! How organisms interact with each other and their environment
! Biological Oceanography ! How the physical and environmental properties of the ocean control biological processes
“How inappropriate to call this planet Earth, when it is quite clearly Ocean”
! Arthur C. Clarke
1 Nov 2017
K. Selph, OCN 201 Fall 2017 3
iClicker Quiz
! Why are you taking OCN 201?
A. Marine Science or GES major
B. I want to be a marine biologist!
C. I like physical oceanography/chemistry or geology!
D. I love whales and dolphins!
E. I’m not in the right classroom……
There’s a lot more to the ocean than whales and dolphins…..
! Origins of Life
! Classification of Life
! Primary Production
! Consumers
! Invertebrates
! Vertebrates
! Marine Community Ecology
! Survival
! Corals and Coral Reefs
! Fisheries
! Marine Food Webs
! Marine Environmental Issues
1 Nov 2017
K. Selph, OCN 201 Fall 2017 4
Origins of Life
Karen E. Selph
What is life? ! Definition of “Life” -
! Self-Replicating
! Self Repairing
! Responsive, Adaptive
! Controlled transformation of matter and energy
! Life on Earth today – ! Cellular
! Water-dependent
! Carbon-based
! Four major components – ! Carbohydrates, Nucleotides,
Protein, Lipid
1 Nov 2017
K. Selph, OCN 201 Fall 2017 5
iClicker Quiz
! Which of these is alive?
A. Rocks
B. Viruses
C. Bacteria & Plants & Animals
D. Fossils
E. Your shoes
Building Blocks of Life ! Carbohydrates
! Monosaccharides ! Glucose, Fructose
! Unmodified - C.H2O
! Fuel & building blocks for nucleic acids
! Disaccharides ! Sucrose, Lactose
! Two monosaccharides
! Fuel
! Oligosaccharides & Polysaccharides ! Longer chains of monosaccharides
! Glycogen, Cellulose, Starch
! Structure & Storage of Energy
1 Nov 2017
K. Selph, OCN 201 Fall 2017 6
Building Blocks of Life ! Nucleotides
! Nucleobase & Sugar & One Phosphate Group ! DNA – Deoxyribonucleic Acid
! Instructions for development and functioning of all living organisms
! Double stranded
! Two long polymers of nucleotides & backbone of sugars & phosphates
! Each sugar has a base that encodes information
! Guanine – Cytosine (3 hydrogen bonds)
! Adenine – Thymine (2 hydrogen bonds)
! RNA – Ribonucleic Acid
! Synthesis of proteins
! Single Stranded
! Structural
Building Blocks of Life ! Proteins (Polypeptides)
! Amino Acids (20) ! Linear chain folded into globular
form ! Short chain – peptide ! Long chain - polypeptide
! Sequence of amino acids defined by sequence of gene
! Three main classes ! Globular Protein
! Enzymes ! E.g. – Hemoglobin
! Fibrous Protein ! Structural ! E.g. - Collagen
! Membrane Protein ! Cell membrane functions ! E.g. – insulin
1 Nov 2017
K. Selph, OCN 201 Fall 2017 7
! TRANSCRIPTION ! Enzymes
! Makes RNA from DNA
! TRANSLATION ! Ribosomes
! Makes amino acids (& proteins) from RNA
DNA
Makes
RNA
Makes
PROTEINS
“central dogma”
Animation of Central Dogma: https://www.dnalc.org/resources/3d/central-dogma.html
1 Nov 2017
K. Selph, OCN 201 Fall 2017 8
Building Blocks of Life ! Lipids
! Structural component of membranes ! Eight Major Lipids
! Fatty Acids ! Immune system & blood pressure
regulation ! Phospholipid
! Lipid bilayers ! Metabolism, Cell signaling
! Sterol Lipids ! Hormones & Signaling molecules ! Cholesterol & Testosterone
! Sphingolipids ! Glycerolipids ! Prenol Lipids ! Saccharolipids ! Polyketides
Element Atomic Percentage Role
Oxygen 8 65 Cellular respiration, water
Carbon 6 18.5 Basis of organic molecules
Hydrogen 1 9.5 Water, organic molecules, electron carrier
Nitrogen 7 3.3 Proteins & nucleic acids
Calcium 20 1.5 Bones, teeth, muscle contraction
Phosphorous 15 1 Nucleic acids, energy transfer
Potassium 19 0.4 Positive ion inside cells, energy transfer
Sulfur 16 0.3 Proteins
Sodium 11 0.2 Positive ion outside cell, nerve function
Chlorine 17 0.2 Negative ion outside cell
Magnesium 12 0.1 Energy transferring enzymes
Iron 26 trace Hemoglobin in blood
Copper 29 trace Enzymes
Molybdenum 42 trace Enzymes
Zinc 30 trace Enzymes
Iodine 53 trace Thyroid hormone
1 Nov 2017
K. Selph, OCN 201 Fall 2017 9
! What are the main building blocks of life?
A. Carbohydrates and fats
B. Lipids and proteins
C. DNA and RNA
D. Carbohydrates, lipids, proteins & nucleotides
E. Beer and chips
iClicker Quiz!
But how was it all put together?
1 Nov 2017
K. Selph, OCN 201 Fall 2017 10
Origin of Life on Earth ! Panspermia (Exogenesis)
! “The seeds of life exist all over the universe and these seeds are transported across the universe”
! “Germs from space landed in our oceans and evolved…..”
! The problem: Challenges of life in space make it unlikely
! Divine Creation (Intelligent Design) ! “Life was created by a divine being 6000 yrs ago”
! “All living things are explained by an intelligent cause not an undirected process such as natural selection”
! The problem: The Earth, and life, are older than 6000 years
! Chemical Evolution (Abiogenesis) ! How life evolved from inanimate matter
! Amino acids can form via natural chemical reactions unrelated to life
! What is the theory of Panspermia?
A. Life started from inanimate matter found on earth millions of years ago
B. Life on earth was kick-started by single celled organisms from space rocks
C. Sperm were the first signs of life on earth and started evolution
D. All living creatures appeared on earth at the same time
E. Fish falling from space and colonizing earth’s oceans
iClicker Quiz!
1 Nov 2017
K. Selph, OCN 201 Fall 2017 11
Where did diversity come from? ! Single-celled organisms
are thought to be first living things on Earth
! How did we get from a single cell to Humans?
! Evolution
! Change in genetic material passed from one generation to the next
! Formation of new species
The Miller-Urey Experiment ! Published 1953
! Simulated conditions 10 mya – primitive Earth
! H2O, Methane, Ammonia, Hydrogen ! Spark – Lightning
! Carbon transformed to organic compounds
! Amino Acids
! Inspired many others – repeated
! Comets & Meteorites found to contain organic compounds
1 Nov 2017
K. Selph, OCN 201 Fall 2017 12
The Origins of Life: a theory http://youtube/U6QYDdgP9eg Movie, inspired by the research of: Dr. Jack Szostak, Harvard
Winner of the 2009 Nobel Prize in Physiology or Medicine
Life came from the Oceans ! Life needs Water
! Photosynthesis & Chemosynthesis uses water
! Transport of molecules in chemical reactions
! Hydrothermal vents ! Source of chemosynthetic energy (H2S)
! Organic molecules not stable at high temperatures, so mixing with cold water necessary…
! Still an ongoing active area of research!
! No matter how it came about, the first replicating form would be acted upon by NATURAL SELECTION
https://imgur.com/gallery/VC9cLvy
https://origin-of-life-gquirke.weebly.com/
1 Nov 2017
K. Selph, OCN 201 Fall 2017 13
Evolution ! Based on two processes
! Heredity ! Traits are passed to offspring
! Recognized early in history, but Gregor Mendel (“father of genetics”) formalized its study using peas (29,000!)
! 50 years later DNA indentified (Watson and Crick) as the carrier of genetic information
! Variation ! Evolution occurs when heritable traits
change
! An individual (phenotype) results both from gene expression (genotype) and environmental influences
! Methods of Evolution ! Natural Selection & Genetic Drift
Major Concepts ! The building blocks of life
! Carbohydrates, Nucleotides, Proteins, Lipids
! How did life begin on earth? ! Most likely theory: Abiogenesis
! Two PROCESSES of evolution ! Heredity & Variation
! Two METHODS of evolution ! Natural Selection ! Genetic Drift
! Diversity on earth comes from ~3.5 billion years of evolution