BIOLOGY 1021 UNIT 1: MULTICELLULAR STRUCTURE CHAPTER 15 P. 307-311 AND CHAPTER 16 P. 328-331
Be sure to know flow chart an understanding from atoms to multicellular organisms. Importance of carbon, hydrogen, proteins, carbohydrates, phospholipids, various cellular organelles and their functions TWO TYPES OF CELLS (Prokaryotic and Eukaryotic) Cell functions: metabolism and transport etc.
REVIEW
REVIEW OF UNICELLULAR ORGANISMS Unicellular 1 cell is the entire organism, microscopic but a highly efficient metabolic machine. All life processes must take place within or by that one cell.. Reproduction Movement Diffusion Osmosis Active transport Respiration DNA replication Protein synthesis enzyme reactions Homeostasis etc.. Unicellular organisms include Bacteria (prokaryotic) and some Protists (Eukaryotic)
Main disadvantage of being unicellular is the fact if the cell is destroyed then the organism is also destroyed! Protection and Reproduction is VERY important! 1. Produce high number of offspring for very large populations. 2. Have capsule (or pellicles), cell wall and membranes for protection. 3. Sexual reproduction to increase genetic variety (need more energy so this type of reproduction is less frequent because they prefer to reserve energy for other metabolic functions needed to survive. 4. Reproduce asexually until it is absolutely necessary to revert to sexual reproduction.
https://study.com/academy/lesson/kingdom-protistadefinition-characteristics-examples.html
PROTISTS: TYPES OF UNICELLULAR ORGANISMS P. 308 1. Protozoans: protists that display characteristics similar to animals. Live in aquatic environments and some parasitic. They are motile (use flagella, pseudopods), eukaryotic and heterotrophic. Ex. Protists (Giardia causes Beaver Fever) (Plasmodium causes Malaria)
TYPES OF UNICELLULAR ORGANISMS P. 309 2. Slime molds protists that appear like fungus but are not related. Unicellular in structure (have many nuclei), able to form colonies that make them quite large in size and fungus-like, they feed on dead plant material. 2 types slime molds and plasmodial slime molds
TYPES OF UNICELLULAR ORGANISMS P. 310 3. Unicellular algae similar to plants because they photosynthesize phytoplankton they support marine food chains and webs. PHYTOPLANKTON Volvox colonial green algae Dinoflagellates bloom cause RED TIDES
TYPES OF UNICELLULAR ORGANISMS P. 310-311 4. Seaweed actually multicellular but each cell is identical and performs its own life processes. (later in notes) classified in 3 different groups (Green, red and brown algae)
UNIT 1: MULTICELLULAR STRUCTURE Multicellular Organisms To be multicellular means the organism is composed to more than one cell. As a result cells are much larger and can be seen with the naked eye (still microscopic but millions and billions of cells together eventfully produces a structure that can be seen.) Multicellular organisms can be simply multicellular or multicellular with a division of labour for life processes!
Simply Multicellular Some protists and fungi They are composed of many cells and are thus visible in terms of size but each cell making up the organism is behaving on its own independent of each other. Like unicellular organisms, each cell is preforming all characteristic of life, if one of the billions of cells making up the organism is destroyed, it will occur unnoticed and the organism continues to function unchanging. The numbers or quantity of cells also offers protection, whereas in a unicellular organism structure is required for protection. Disadvantage requires excessive energy
2 types of multicellular organisms Simple no division of labour 1. Multicellular protists 2. Multicellular fungi
1. MULTICELLULAR SEAWEED Seaweed multicellular but no division of labour. Every cell making up the seaweed will perform all the same functions regardless of their location on the seaweed body.
SEAWEED Seaweed the grow on rocky shores are subject to coastal action harsh environment but need to live here because they need access to sunlight to photosynthesize. Every cell photosynthesizes, are well protected, perform all their own life processes therefore no need to an elaborate transport system. Because they are simply multicellular, they no not have any form of skeletal or support system which explains why, out of water, they have no shape. They simply rely on water for support.
Seaweed look like plants and are structurally like plants BUT They have a holdfast that looks like a root actually holds it to the rock They have a stipe which looks like a stem They have a blade which looks like a leaf In seaweeds there are no tissues, organs or organ systems, all cells are identical. Cells of the seaweeds holdfast, stipe and blade are all similar in appearance and perform all the same functions every cell photosynthesize. Roots, stems and leaves of a plant are organs composed of very different tissues with different functions. The leaves of a plant are designed for photosynthesis The root of the plant are underground and is designed for anchorage and uptake of water and nutrients different function different cells so no chloroplasts
1I. MULTICELLULAR FUNGI P. 328 Kingdom Fungi is made up of multicellular eukaryotic cells that also does not form tissues, organs or systems. Cells are not like other eukaryotic cells but appear as long threads so long that one nuclei cannot control the entire length therefore several nuclei are present. These cells are called hyphae. Fungi are composed of numerous hyphae that can make the fungi large in size (ex. Mushroom) All cells or hyphae are absorptive heterotrophs with the ability to produce substances to dissolve nutrients that can then be absorbed into the cell. All cells or hyphae contain cell walls comprised of chitin for support as they do not have a support or skeletal system.
All the hyphae in a mushroom are the same above ground in the cap or in the stalk that is below ground. (no division of labour)
Fungi are very important decomposers. They help recycle nutrients. P. 330 Beneficial. Eat mushrooms and truffles Culture fungi to produce antibiotics and other drugs - Penicillin Culture to make cheese and ferment alcohol Make bread rise They can also be parasitic Vaginal yeast infections, athletes foot, jock itch
2. Multicellular with division of labour An organism of many cells that conserves energy, by division of labour for life processes. The division of labour conserves energy via brining each organelle together as a team and gives each a certain function. This creates a much more efficient organism. Cells Tissues Organs Organ systems To be multicellular with division of labour, the organism must have tissues, organs and organ systems rather than just simply composed of many cells
The organisms as a result will be much larger, more complex and highly efficient! Although losing one cell may not be as detrimental in term of the organism as a whole, all components of the system must work together since they are concerned only with their own function. Therefore, losing a tissue, organ and especially an organ system WILL be detrimental to the organism as a whole, since then the entire function will also be lost.
Tissues a group of cells of similar shape and size that perform one specific function. Ex. Muscle tissue many cells working together to perform the function of movement or contraction OR Nervous tissue many cells working together to perform their function of receiving and transmitting impulses. Organs a group of tissues working together for a specific function. Ex. Stomach is an organ composed of several tissue types such as epithelial tissue, muscle tissue ans connective tissue, all working for breakdown of materials. Organ system A group of organs working together for a specific function. Ex. Digestive system is composed of various organs such as the stomach, intestine, colon whose function is digestion. The cardiovascular system is composed of vital organs such as the heart, veins, arteries that work together for transport.
LAB # 1