chapter 10 – multicellular organisms 10-1 – how they meet needs 10-2 – plants are producers...
TRANSCRIPT
Chapter 10 – Multicellular Organisms
10-1 – How they meet needs
10-2 – Plants are producers
10-3 – Animals are consumers
10-4 – Fungi are decomposers
Chapter 10-1 – Meeting needs
Multicellular organisms (mo’s) have cells that are specialized. In single-celled organisms, all functions are performed by each cell.MO’s life functions (getting energy/raw materials, waste removal, responding to changes in environ, reproducing) - done by specialized cells.
10-1 Levels of Organization
MO’s cells must work together for an organism to survive.Specialized organization starts with the cells (ex. Skin, nerve, muscle are different)Cells of same type = tissueDifferent tissues working together to perform the same function = organOrgans have different functions
10-1 Organ SystemsOrgan systems have multiple organs
working together (ex: nervous, respiratory, muscular, circulatory, digestive) to perform the same function & help organism surviveNervous = enables responses to changing conditionsMuscular = movement & heatRespiratory = Oxygen in; CO2 outCirculatory = delivers oxy. & removes CO2.Digestive = breaks down food into useable form
10-1 MO’s have varied adaptations
Adaptation– any inherited characteristic (shape, structure, behavior, etc) that increases an organism’s ability to survive & reproduce offspring that reproduce.
Single celled organisms reproduce A-sexually (only 1 parent; offspring identical to parent)
10-1 Sexual Reproduction & Diversity
Most MO’s reproduce sexually (2 parents needed; offspring’s DNA not identical to parents)Sexual Reproduction:
Meiosis = cell division that produces male sperm and female egg cells which contain one copy of DNA instead of 2.Fertilization = sperm and egg cell unite & new cell has 2 sets of DNA male/female
10-1 Sexual Reproduction cont.
Most multi-celled organisms reproduce sexually. Some do not example: “budding” in plants
Differences in genetic material and in the environment produce differences in offspring.
How well something grows depends on both genetics and environment.
10-1 Benefits & Drawbacks
Organisms that reproduce asexually can reproduce more often, but lack lack genetic diversity within a group.MO’s that reproduce sexually reproduce less often, but have greater genetic diversity due to having 2 sets of DNA (half from each parent). So new combinations allow for greater diversity/adaptations in offspring.
10-2
Plants
Are
Producers
10-2 Plants Are Producers
Plants capture energy from the sun.Energy from the sun cannot drive cell processes directly.Light energy must be changed into chemical energy (photosynthesis).Chemical energy is the form of energy that all organisms need to carry out life.
10-2 Producing Sugars
Photosynthesis = process by which sunlight energy is transformed into chemical energyRaw Materials: Water and CO2 are used in the production of sugarsBy-Products of Photosyn = O2 (oxygen) + sugar and/or starchMost photosynthesis takes place in the leaves; (autotroph=self feeder)Roots, Stems, Leaves, etc.=organ sys.
10-2 Storing & Releasing Energy
Algae, bacteria, protists can also use photosynthesisPlants are MO’s and can store energy, where simple 1-celled organisms cannot.Plants store excess sugars as starches & use them for growth.Starches can store chemical energyCellular respiration is the process by which a cell uses oxy. To break down sugars & release energy
10-2 – Plants are adapted
Plants are adapted to different environments. (Different leaves, stems, roots, etc)
Coniferous = cone bearing (ex.pine)
Deciduous = trees that lose leaves in different seasons (oak, maple)
Other adaptations: how quickly they flower & seed themselves
10-2 Respond to Environ.
Stimulus = something that produces a response from an organism
Examples: gravity=roots grow down; sunlight = leaves turn towards it; flowers open/close
Touch = plant touches another object and plants tendrils wrap around that object.
10-2 Respond to Environ.Hormone = a chemical substance produced in one part of organism that travels to another part of the organism where it produces a reaction or response.Auxin = a hormone that stimulates cell growth in the tip of a plants stem (or root). Auxins on the dark side of a plant contain more auxins (which avoid light) than cells on the lighted side of a plant.
10-2 Seasonal Changes
Shorter period of sunlight (fall/winter) affect photosynthesis time.
Seasonal changes trigger plant “dormancy” when plants stop growing to conserve energy
Plants also may change leaf colors & drop leaves due to seasons.
Seasons also affect seed production
10-3
Animals
Are
Consumers
10-3 Food = Energy
Consumer = an organism that needs to get energy from another organism.
Animals are heterotrophs (organisms that feed on or consume other organisms).
Animals seek food by grazing, hunting, etc
10-3 What Animals Eat
Herbivores = organisms that feed on plants or algae.
Examples: Cows, ducks
Carnivores = feed on other animalsExample: Lions, wolves
Omnivores = feed on both plants and animals.
Bears, Mice
10-3 Processing Food f/Energy
Energy is stored in complex carbon compounds which must be broken down into simpler compounds.
Digestion is the process that breaks down food into useable size using both physical and chemical activity.
Food enters mouth & as it moves through the system, it’s broken down, releasing energy/nutrients, and waste is expelled at the other end of the digestive system.
10-3 Releasing & Storing Energy
Animals get energy from sugars and other carbon compounds the same way plants do (cellular respiration).
Animals/plants both take H20 through their digestive systems
Animals have varied structures for getting O2 (gills, spiracles, lungs, etc).
Animals must store food in tissues/organs for later use.
10-3 Animal Interactions
Animal bodies have many adaptations (systems) that allow it to process food (digestive, respiratory, circulatory).Other systems allow interaction w/environment (muscular, skeletal, nervous, etc.)Behavior = an observable response to a stimulus (light, sound, odor, temperature.sight, etc)
10-3 Three Behavior Categories
Individual BehaviorsEx: Often involve meeting basic needs (food, water, shelter, sleep, grooming)
Animal to animal of same species or “social behaviors”
Ex: Parent to offspring; attracting mates; group hunting (wolves); bees in hive
Animal to animal of different speciesEx: Predator-Prey behaviors; or mutualism (tickbirds removing ticks from impala)
10-3 Animals Seasonal responses
Animals respond to seasonal changes in their environment (drought, heat, cold)
Migration – the movement of animals to a different region in response to an environmental change. (Ex: birds, butterflies, wildebeast, elephants, etc.)Hibernation – a sleeplike state that lasts for an extended time period. (Ex. Frogs, turtles, fish, bears, etc.)
10-4 Fungi
Fungi
Are
Decomposers
10-4 Fungi Absorb Materials
Most fungi are decomposers that break down complex carbon compounds and use them for energy and raw materials.
They absorb nutrients and leave behind simpler compounds
Fungi are heterotrophs
10-4 Characteristics of Fungi
Yeast = unicellular fungi; All other fungi are MO’s (multi-cellular).
Organization: Cells have nucleus, thick cell walls
Do not have: specialized tissues or organs.
Do have: reproductive body & hyphae (thread-like structures, one cell thick).
Mycellum = a mass of hyphae
10-4 Reproduction of Fungi
Fungi reproduce with spores which can be produced either asexually or sexually.
A spore is a single reproductive cell that is capable of growing a new organism.
Spores are air-borne, spread by wind, and can survive many years.
Fungi can also reproduce asexually by breaking off hyphae & regrowing a new fungi; they can also “bud” (yeast)
10-4 What are Fungi?
Mushrooms – The outer part of a mushroom is only part of the fungus. The mushroom’s hyphae/mycellum is underground
Molds – Spore producing part of another type of fungus.
Yeasts = Single celled fungi; need moisture, heat
10-4 Helpful? Or Harmful?Fungi are Earth’s main decomposers.Helpful:
Penicillin is an antibiotic that helps treat disease and make cheese (brie, Camembert, and blue cheese). Penicillin keeps bacteria from forming new cell walls during reproduction so bacteria cells break open and die.Aspergillis fungus used to make soy sauce.Trichoderma is used in making stone-washed jeans.
10-4 Harmful FungusMany molds cause disease. (Athlete’s food; Dutch Elm Disease; Powdery Mildew) 1845 Irish potato famine was caused by a potato fungus which produced toxins, disease & famine which killed 4 million people.Lichen = fungi that live together with a single-celled algae forming a sort of “sandwich” around the algae.