Chapter 5 Biological Concepts Karleskint Turner Small
Key Concepts All living organisms are composed of cells. Cells can be either prokaryotic or eukaryotic Cells produce new cells by the process of cell division Evolution is the process by which the genetic composition of populations of organisms changes over time Natural selection favors the survival and reproduction of those organisms that possess variations that are best suited to their environment
Key Concepts A species is a group of physically similar, potentially interbreeding organisms that share a gene pool, are reproductively isolated from other such groups, and are able to produce viable offspring. The binomial system of nomenclature uses two words, the genus and the species epithet, to identify an organism.
Key Concepts Most biologists classify organisms into one of three domains, categories that reflect theories about evolutionary relationships. Phylogenetic trees and cladograms indicate evolutionary relationships among groups of organisms
What makes you a Human? IQ#1: What are humans composed of???
CELLS: Fundamental Unit for Life and Death.
Cells All cells are capable of: metabolism Growth (mitosis)- cells grow and replicate ex. Skin cells regrow. Reproduction (meiosis)- egg and sperm cells combine to create a new cell an offspring
Types of Cells Prokaryotic cells Eukaryotic cells
Prokaryotic Cell Architecture Prokaryotic Diversity Prokaryotic cells are diverse and classified in two domains: Archaea (Archaebacteria) and Bacteria (Eubacteria) Prokaryotes come in all shapes and sizes, and all are single cell organisms They can live in social groups, and form chains, clusters or films. Ex. Biofilm in your bath tub
Prokaryotes Prokaryotes: Contain a cell wall made of peptidoglycan Lack internal membranes membrane bound organelles Contain a primitive cytoskeleton Move simply through their flagellum
IQ#2 Antibiotic medicine kill bacterial cells Scenario: You have a flu which is caused by a virus, however you take an antibiotic to help cure yourself what do you think happens?
Common Misconceptions DO you know the difference between a virus and a bacterial cell? Virus are even smaller than bacteria! Viruses require a living host to multiply. Otherwise they cant survive. Therefore, you can conclude that virus are asleep until they meet a host. When a virus enters your body, it hijacks some of your cells and takes over the cell machinery, redirecting it to produce the virus.
Prokaryotic genetic Features DNA storage, structure and replication for division are distinguishing features for prokaryotic cells Prokaryotes: contain a circular nucleoid where DNA is packed No organelles Small amounts of DNA Some have plasmids that contain extra DNA Binary fission is the process through which cells divide A complete copy of DNA is passed on to a daughter cell Genetic information can be shared between organism's aka bacteria can have sex
IQ#3 Are Viruses prokaryotes or eukaryotes? Can you explain why?
3 points learned 1. 2. 3. Reflection 3 points confused 1. 2. 3.
Organelles Nucleus and ribosomes Nucleus: contains the cell s DNA and acts as the control center Ribosomes endoplasmic reticulum rough ER smooth ER
Organelles Golgi apparatus lysosomes Vacuoles chloroplasts mitochondria Flagella Cilia
Animal Cell Organelles
CYTOSKELETON Structurally supports, imparts shape to cell; moves cell and its components microtubules microfilaments intermediate filaments nuclear membrane nucleolus DNA in nucleoplasm NUCLEUS Keeps DNA and its transcription into RNA away from potentially damaging reactions in cytoplasm MITOCHONDRION Energy powerhouse; produces much ATP by aerobic respiration CENTRIOLES Special centers that produce and organize microtubules CELL MEMBRANE Selectively controls the kinds and amounts of substances moving into and out of cell; helps maintain cytoplasmic volume, composition ROUGH ER Modifies new polypeptide chains SMOOTH ER Diverse roles; e. g., makes lipids, degrades fats, inactivates toxins GOLGI BODY Modifies, sorts, ships proteins and lipids for export or for insertion into cell membranes LYSOSOME Digests, recycles materials Figure 5-7b p102
Plant Cell Organelles
CYTOSKELETON Structurally supports, imparts shape to cell; moves cell and its components CELL WALL Protects, structurally supports cell microtubules microfilaments intermediate filaments (not shown) MITOCHONDRION Energy powerhouse; produces much ATP by aerobic respiration CELL MEMBRANE Selectively controls the kinds and amounts of substances moving into and out of cell; helps maintain cytoplasmic volume, composition CHLOROPLAST Specializes in photosynthesis CENTRAL VACUOLE Increases cell surface area, stores metabolic wastes LYSOSOME-LIKE VESICLE Digests, recycles materials nuclear membrane nucleolus DNA in nucleoplasm NUCLEUS Keeps DNA and its transcription into RNA away from potentially damaging reactions in cytoplasm ROUGH ER Modifies new polypeptide chains SMOOTH ER Diverse roles; e. g., makes lipids, degrades fats, inactivates toxins GOLGI BODY Modifies, sorts, ships proteins and lipids for export or for insertion into cell membranes Figure 5-7a p102
Energy Transfer in Cells Photosynthesis low-energy molecules combine to form highenergy food molecules chloroplasts
Two outer membranes Thylakoids (inner membrane system folded into flattened disks) Figure 5-10a p105
Energy Transfer in Cells
Sun O 2 Glucose (energy-rich) Algae and phytoplankton (autotrophs) Animals (heterotrophs) Seagrass and seaweed (autotrophs) PHOTOSYNTHESIS CELLULAR RESPIRATION CO 2 + H 2 O (energy-poor) Figure 5-9 p104
Energy Transfer in Cells Cellular respiration releases energy from food molecules most occurs within mitochondria food molecules are broken down to create ATP and release CO 2 as a waste product
Outer membrane Outer compartment Inner compartment Inner membrane Figure 5-10b p105
Cellular Reproduction Cell division in prokaryotes single chromosome binary fission
Chromosome Chromosome is duplicated Two new cells (a) Prokaryote Figure 5-11a p106
Cellular Reproduction Cell division in eukaryotes Mitosis Cytokinesis
Chromosomes separating Chromosomes (b) Eukaryote Two new nuclei Figure 5-11b p106
Levels of Organization cells are grouped into tissues different tissues combine into organs groups of organs make up organ systems
a cell Smallest unit that can live and reproduce on its own or as part of a multicelled organism. It has an outer membrane, DNA, and other components. Figure 5-12a p107
b tissue Structural unit of certain types and proportions of cells interacting in some task. Many cells ( white ) made this bone tissue from their own secretions. Figure 5-12b p107
c organ Structural unit of two or more tissues interacting in some task. A parrotfish eye is a sensory organ used in vision. Figure 5-12c p107
d organ system Organs interacting physically, chemically, or both in some task. Parrotfish skin is an integumentary system with tissue layers, organs such as glands, and other parts. Figure 5-12d p107
e multicelled organism Individual made of different types of cells. Cells of most organisms, including this Red Sea parrotfish, are organized as tissues, organs, and organ systems. Figure 5-12e p107
3D ANIMATION: Tour of an Animal Cell
3D ANIMATION: Photosynthesis Bio Experience 3D
3D ANIMATION: Mitosis
ANIMATION: Common eukaryotic organelles To play movie you must be in Slide Show Mode PC Users: Please wait for content to load, then click to play Mac Users: CLICK HERE
ANIMATED FIGURE: Flagella structure To play movie you must be in Slide Show Mode PC Users: Please wait for content to load, then click to play Mac Users: CLICK HERE
ANIMATED FIGURE: Structure of a mitochondrion To play movie you must be in Slide Show Mode PC Users: Please wait for content to load, then click to play Mac Users: CLICK HERE
INTERACTION: Structure of a chloroplast To play movie you must be in Slide Show Mode PC Users: Please wait for content to load, then click to play Mac Users: CLICK HERE
INTERACTION: Structure of a mitochondrion To play movie you must be in Slide Show Mode PC Users: Please wait for content to load, then click to play Mac Users: CLICK HERE
ANIMATION: Sites of photosynthesis To play movie you must be in Slide Show Mode PC Users: Please wait for content to load, then click to play Mac Users: CLICK HERE
ANIMATED FIGURE: Overview of aerobic respiration To play movie you must be in Slide Show Mode PC Users: Please wait for content to load, then click to play Mac Users: CLICK HERE
ANIMATED FIGURE: Prokaryotic fission To play movie you must be in Slide Show Mode PC Users: Please wait for content to load, then click to play Mac Users: CLICK HERE
ANIMATED FIGURE: Typical prokaryotic cell To play movie you must be in Slide Show Mode PC Users: Please wait for content to load, then click to play Mac Users: CLICK HERE
ANIMATION: Generalized animal cell
ANIMATION: Generalized plant cell
Evolution and Natural Selection Evolution the process by which populations of organisms change over time Evolutionary biology investigates: how and when organisms evolved what role the environment plays in determining the characteristics of organisms that can live in a given area
Darwin and the Theory for Evolution Voyage of discovery Darwin traveled on the HMS Beagle for 5 years, beginning in 1831 Darwin was influenced by Charles Lyell and other geologists who concluded that: since geological change is slow and continuous, the earth is very old slow and subtle changes become substantial when they continue for centuries/millennia
Darwin and the Theory for Evolution Formulating a theory for evolution Darwin was inspired by Thomas Malthus Darwin developed his hypothesis evolution by natural selection Published On the Origin of Species by Means of Natural Selection
Darwin and the Theory for Evolution Theory of evolution by natural selection artificial selection similar process was occurring in nature? natural selection favors survival and reproduction of those organisms best suited to their environment
Darwin and the Theory for Evolution Four basic premises of Darwin s theory 1. All organisms produce more offspring than can possibly survive to reproduce. 2. Variation in inherited traits 3. Resources are limited 4. Traits that make individuals better adapted to their environment are more successful, and pass on those traits to their offspring.
Genes and Natural Selection Modern evolutionary theory Darwin s 1858 idea refined by modern genetics genes produce traits can exist in alleles the offspring receives 1 allele for a trait from each parent, producing many possible combinations
a A pair of homologous chromosomes, each in the unduplicated state (most often, one from a male parent and its partner from a female parent) b c A pair of alleles (each being a certain molecular form of a gene) on a pair of homologous chromosomes Three genes; regions of DNA that code for specific proteins. Figure 5-15 p110
Genes and Natural Selection Role of reproduction in asexual reproduction, offspring are clones variation results from mutation only
ASEXUAL REPRODUCTION Figure 5-16a p111
Genes and Natural Selection Role of reproduction in sexual reproduction, chromosomes from 2 parents are combined
Fertilized egg Sperm Egg SEXUAL REPRODUCTION Figure 5-16b p111
Genes and Natural Selection Role of reproduction meiosis forms haploid cells called gametes
Genes and Natural Selection Population genetics Organisms adapt to survive ability to adapt is limited by the gene pool Only individuals that have combinations of genes and alleles that allow adaptations to their surroundings are likely to survive and reproduce Reproduction is success
Evolution of New Species Typological definition of species based on morphology
Evolution of New Species Modern species definition a species is one or more populations of potentially interbreeding organisms that are reproductively isolated from other such groups reproductive isolation: members of a different species are not in the same place at the same time or are physically incapable of breeding, so genes from different species are not mixed
Evolution of New Species Modern species definition isolating mechanisms that prevent fertilization habitat isolation anatomical isolation behavioral isolation temporal isolation biochemical isolation
Evolution of New Species Post fertilization isolating mechanisms incompatible genes or biochemical differences the hybrid offspring may survive but be infertile or weak
Evolution of New Species Allopatric speciation
Single population of spotted cowry (ancestral species) Figure 5-19a p114
Species B (measled cowry) Species A (Little deer cowry) Figure 5-19b p114
3D ANIMATION: Meiosis
ANIMATED FIGURE: Genetic terms To play movie you must be in Slide Show Mode PC Users: Please wait for content to load, then click to play Mac Users: CLICK HERE
ANIMATED FIGURE: Reproductive isolating mechanisms To play movie you must be in Slide Show Mode PC Users: Please wait for content to load, then click to play Mac Users: CLICK HERE
ANIMATION: Models of speciation To play movie you must be in Slide Show Mode PC Users: Please wait for content to load, then click to play Mac Users: CLICK HERE
ANIMATED FIGURE: Allopatric speciation on an archipelago To play movie you must be in Slide Show Mode PC Users: Please wait for content to load, then click to play Mac Users: CLICK HERE
Classification: Bringing Order to Diversity Linnaeus and the binomial system
Classification: Bringing Order to Diversity Taxonomic categories Early schemes of classification all living things were classified into 1 of 2 kingdoms, Animalia and Plantae, until 1960s
Classification: Bringing Order to Diversity Modern classification major categories: domain, kingdom, phylum, class, order, family, genus, and species domains: Archaea, Eubacteria, Eukarya kingdoms: Eukarya contains 3 kingdoms, Fungi, Plantae and Animalia protists: eukaryotic organisms that do not fit the definition of animal, plant or fungus
Classification: Bringing Order to Diversity Modern classification
Bacteria Archaea Protista Plantae Protista Animalia Fungi Common ancestor of all eukaryotes Common ancestor of all living organisms Figure 5-22 p116
Classification: Bringing Order to Diversity Phylogeny: phylogenetic tree phenetics cladistics
Lungfishes Amphibians Turtles Lizards, snakes Tuataras Crocodiles Birds Mammals Coelacanths Bony fishes Cartilaginous fishes Lampreys Hagfish Figure 5-24a p119
Hagfish Shark Sea turtle Seal Hair, mammary glands 4 Limbs Jaws Common vertebrate ancestor Figure 5-24b p119
ANIMATED FIGURE: Classification systems To play movie you must be in Slide Show Mode PC Users: Please wait for content to load, then click to play Mac Users: CLICK HERE
ANIMATED FIGURE: Interpreting a cladogram To play movie you must be in Slide Show Mode PC Users: Please wait for content to load, then click to play Mac Users: CLICK HERE