BIOLOGICAL SCIENCES

By:

MARIA KRISIA FAE DELOS REYES DE ASIS, BSN-RN

CLASSIFY!

WOLFKINGDOM: AnimaliaPHYLUM: ChordataClass: MammaliaOrder: CarnivoraFamily: CanidaeGenus: CanisSpecies: lupus

CLASSIFY!

LIONKINGDOM: AnimaliaPHYLUM: ChordataClass: MammaliaOrder: CarnivoraFamily: FelidaeGenus: PantheraSpecies: leo

CLASSIFY!

WALRUSKINGDOM: AnimaliaPHYLUM: ChordataClass: MammaliaOrder: PinnipediaFamily: OdobenidaeGenus: OdobenusSpecies: rosmarus

CLASSIFY!

BLUE WHALEKINGDOM: AnimaliaPHYLUM: ChordataClass: MammaliaOrder: CetaceaFamily: BalaenopteridaeGenus: BalaenopteraSpecies: musculus

CLASSIFY!

POLAR BEARKINGDOM: AnimaliaPHYLUM: ChordataClass: MammaliaOrder: CarnivoraFamily: UrsidaeGenus: UrsusSpecies: maritimus

CELLULAR LEVEL OF ORGANIZATION

+ MATTHIAS SCHLEIDEN- Stated that all plants are composed of cells

+ THEODOR SCHWANN- Stated that all animals are composed of cells

+ RUDOLF VIRCHOW- Used a microscope to study the life of cells

CELL THEORY

= states that all organisms are composed of cells and that cells come only from preexisting cells

+ ROBERT HOOKE- First person to use the term “cell”

CELL

= the structural and functional unit of organs and organisms

= “building block of life”

+ CYTOLOGY- Study of cells

CELL COMPONENTS

= PROTEINS, NUCLEIC ACIDS, CARBOHYDRATES and LIPIDS are the four major molecules that underlie cell structure and also participate in cell function

+ Plasma membrane- Formed by a tightly organized arrangement of lipids, proteins, and protein-sugar compounds

CELL COMPONENTS

= PROTEINS, NUCLEIC ACIDS, CARBOHYDRATES and LIPIDS are the four major molecules that underlie cell structure and also participate in cell function

CELL COMPONENTS+ ENZYMES- Specialized proteins that speed up chemical reactions

+ RIBONUCLEIC ACID (RNA)- works with DNA to build the thousands of proteins the cell needs+ DEOXYRIBONUCLEIC ACID (DNA)- Nucleic acid that contains the hereditary information for cells

CELL STRUCTURE

O PROKARYOTIC- all the components, including the DNA, mingle freely in the cell’s interior as a single compartment

O EUKARYOTIC- contain numerous compartments, or organelles, within each cell

PROKARYOTIC CELL

= Among the smallest of all cells= can be rodlike, spherical, or spiral in shape, are surrounded by a protective CELL WALL

+ PLASMA MEMBRANE-composed of two layers of flexible lipid molecules and interspersed with durable proteins-selectively permeable

PROKARYOTIC CELL

+ CYTOPLASM-Semifluid that fills the cells and enclosed by the plasma membrane

+ RIBOSOMES-The only organelle in prokaryotic cells-Tiny bead-like structures that serve as the cell’s protein factories (PROTEIN SYNTHESIS)

PROKARYOTIC CELL

+ DEOXYRIBONUCLEIC ACID (DNA)-a complex molecule in the form of a double helix-it repeatedly twists and folds to form a compact structure called a CHROMOSOME-Found within the cytoplasm of a prokaryotic cell (nucleoid)-divided into units called GENES found in the PLASMID

EUKARYOTIC ANIMAL CELL

= typically about ten times larger than prokaryotic cells

+ PLASMA MEMBRANE-it separates the cell from its surroundings and regulates the traffic across the membrane

+ CYTOPLASM-Semifluid that fills the cells and enclosed by the plasma membrane-house a nucleus and numerous other membrane-enclosed organelles

EUKARYOTIC ANIMAL CELL

ORGANELLES:

o NUCLEUS-surrounded by a double-layered membrane that protects the DNA from potentially damaging chemical reactions that occur in the cytoplasm-Command center of the cell-In constant communication with the cytoplasm

EUKARYOTIC ANIMAL CELLo ENDOPLASMIC RETICULUM-An elongated membranous sac attached to the nuclear membrane

+ Rough Endoplasmic Reticulum-Studded with ribosomes-Function: PROTEIN SYNTHESIS, forms VESICLES (in which large molecules are transported to other parts of the cell – plasma membrane or Golgi apparatus)

EUKARYOTIC ANIMAL CELL

+ Smooth Endoplasmic Reticulum-Has no attached ribosomes-Function: LIPID SYNTHESIS (phospholipids & steroids)-Other functions are dependent on the type of cell (ex. Testes – produces testosterone, Liver – detoxifies drugs)

EUKARYOTIC ANIMAL CELL

o GOLGI APPARATUS-Named after Camillo Golgi-An organelle that resembles a stack of pancakes-“packaging center of the cell”-packed with enzymes that complete the processing of proteins and lipids by sorting and packaging them in vesicles for transport

EUKARYOTIC ANIMAL CELL

o LYSOSOMES-small, often spherical organelles that function as the cell’s recycling center and garbage disposal-Powerful digestive enzymes break down worn-out organelles and ship their building blocks to the cytoplasm where they are used to construct new organelles-also dismantle and recycle proteins, lipids, and other molecules

EUKARYOTIC ANIMAL CELL

o MITOCHONDRIA-Powerhouses of the cell-enzymes convert the sugar glucose and other nutrients into adenosine triphosphate (ATP)-they contain their own DNA in the form of a prokaryote-like circular chromosome; have their own ribosomes, which resemble prokaryotic ribosomes; and divide independently of the cell

+ CYTOSKELETON- a dynamic network of protein tubes, filaments, and fibers, crisscrosses the cytoplasm, anchoring the organelles in place and providing shape and structure to the cell

EUKARYOTIC ANIMAL CELL

EUKARYOTIC PLANT CELL

= have all the components of animal cells with several added features, including chloroplasts, a central vacuole, and a cell wall

+ CHLOROPLASTS-convert light energy into the sugar glucose by means of photosynthesis

+ VACUOLE-stores water, salts, sugars, proteins, and other nutrients-it stores the blue, red, and purple pigments that give certain flowers their colors-also contains plant wastes that taste bitter to certain insects, thus discouraging the insects from feasting on the plant

EUKARYOTIC PLANT CELL

+ CELL WALL-surrounds and protects the plasma membrane-Its pores enable materials to pass freely into and out of the cell-The strength of the wall also enables a cell to absorb water into the central vacuole and swell without bursting-provides plants with rigidity and support for stems, leaves, and flowers

EUKARYOTIC PLANT CELL