Week Of: 5/13
6th Grade Unit B Chapter 4 Lesson 4 What Are Biomes?
On land a number of major types of ecosystems are described by their climates and the
communities that live there.
Climate- is one of the most important factors that determine the kinds of organisms
found in a biome.
Biomes- geographic regions with a particular kind of climate and community (plants and
animals that live there)
- change as latitude or distance from the equator changes because climate
changes with latitude
- regions near the equator have warmest climates, regions near the poles
have the coldest climates, regions with middle latitudes have climates with
- coldest and most northern biome (next to the polar ice caps)
- the ground below remains frozen all year long (permafrost)
- get very little precipitation
- ground is snow covered most of the year
- animals have thick fur and extra layers of fat that help them to stay warm
- plants have small, tough leaves with waxy coatings to prevent moisture from escaping
- animals in the Tundra include: polar bears, wolves, caribou, mice which either migrate, hibernate or grow thick fur to survive the harsh conditions
- birds in the Tundra include: geese, ptarmigans, snowy owls
- insects in the Tundra include: flies, mosquitoes
Please see below for NOTES given during the past 2 weeks Quiz Schedules for Thursday. and Test Scheduled for next Tuesday on Chapter 4.
The following notes were done in class last week. For those who were absent please copy into to your notebook to be prepared for quiz and test coming soon.
6th Grade Unit B Chapter 4 Lesson 3 How Do Organisms Interact?
Limiting Factors-Competition For Resources
In an ecosystem organisms compete for space, light, food, water, air, and nutrients.
Competition- is the struggle among organisms for limited resources in an area.
Every ecosystem has limited resources so all species must compete to stay alive. There are several types of competition in an ecosystem. Some types include:
1. one species might prevent another from using an important resource
Ex. some plants in the desert release certain chemicals into the
soil to keep other plants from growing
2. the predator-prey relationship also affects competition for resources
in an ecosystem
predator- an animal that hunts and kills and eats other living
prey- an animal that predators eat
Organisms Interact To meet Their Needs
Symbiosis- a close relationship between organisms of different species in which one or both of the organisms benefit
There are 3 types of symbiosis:
1. parasitism- one species benefits while the other is harmed
Parasite- an organism that lives in or on another organism
- Usually smaller than the host
- Some live on the outside of the host
Ex. ticks and fleas live on the hosts skin
Host- an organism that a parasite lives in or on
2. mutualism- both organisms benefit
Ex. flowers provide bees with nectar for food
3. commensalism- one organism benefits and the other organism is
neither harmed or helped
Ex. barnacles stick to the surface of organisms so they
can feed easily on the tiny organisms it filters
from the water
also happens on your body with the millions of
bacteria that live on your skin
5/14 Quiz on Thursday Ch. 4 Test on Ch. 4 Next Tuesday
Answer the following questions in your notebook
1. How does precipitation change in forests as you move from the equator toward the poles?
2. How does having a waxy surface help leaves withstand the taiga’s climate?
3. What characteristics of fall might trigger the end of production of chlorophyll in tree leaves?
4. What differences are there between plants in a rain forest and those in a temperate deciduous forest?
5. What major characteristics does the desert share with the tundra?
6. Why would a tundra animal need to conserve energy in winter?
7. What biome is the coldest?
Select an animal from your biome. Create a food chain that includes your animal along with at least 2 other animals. YOu may use pictures from the internet. Label each organism as either a producer or consumer.( 1st level, 2nd level.) Begin with the sun!
Lesson 2 Notes for those who were absent:
6th Grade Unit B Chapter 4 Lesson 2 How Do Organisms Get Energy?
All living things need energy to move, eat, grow and reproduce.
The sun is the source of energy in almost all ecosystems and therefore is the first step in most food chains.
Producer- an organism that makes its own food
Ex. green plants make their own food in the process of photosynthesis- plants use energy from the sun to turn carbon dioxide from the air and water and nutrients from the soil into glucose(sugar)
Food Chain- a sequence of connected producers and consumers
Consumer- an organism that eats other organisms
- A primary consumer is a herbivore- an animal that eats only plants
- A secondary consumer is a carnivore- a meat eating animal
- A consumer that is both plant and meat eating is an omnivore
Scavengers- eat the remains of dead animals
Decomposers- consumers like bacteria and fungi that break down plant and animal wastes and return the nutrients in them to the soil
Food Web- a group of connected food chains in an ecosystem
- Most organisms eat more than one type of food.
- Each food web contains several food chains.
Q: What would happen in the land food web if the mice decreased or disappeared?
A: The animals that feed on the mouse would have less food and as a result their populations would decrease
The Energy Pyramid
Energy Pyramid- shows that energy is lost at each level of the food chain
- Energy is lost each time it passes from one organism to another
- Scientists have found that 90% of an organisms energy is lost at each step of the food chain
- This loss means that only 10% of the stored energy is passed on to the next organism in the food chain-
Please have these done by Monday, May 13
6th Grade Unit B Chapter 4 Lesson 3 Critical Thinking
1. For what things do organisms compete with each other?
2. Predict what happens to an animal that competes with people for habitat.
3. Using the chart on page 219, when was the hare population the greatest?
4. Using the chart on 219, what happened to the two populations around year 15?
5. What effect does mutualism have on organisms?
6. How do mutualism and commensalism compare?
7. How are the effects of commensalism and parasitism different?