Science 8Name: ____KEY______
Cells and Systems UnitSection: ______
Chapter 1 – Cells
Section 1.1 – The Characteristics of Living Things (page 5-6)
List the 6 characteristics of living things. Refer to Table 1 on page 5.
1.a) Living things are made up of cells.
- all cells are similar
- plants are similar to other plants
- animals are similar to other animals
- ex. skin cells, heart cells, etc
b) Living things reproduce, grow and repair themselves.
- cells reproduce by dividing into two
- new cells are needed for growth and repair
- ex. cell reproduction, wound healing, growing
c) Living things require energy.
- plants get energy from sunlight
- animals get energy from eating plants/animals that got their energy from sunlight
- ex. grade 7 food chains/webs
d) Living things respond to the environment.
- respond to other organisms
- respond to climate factors
- adaptations, move territory, protect territory
e) Living things have a life span.
- exist for a limited time period
- Ex. human life span 78 years, fruit flies live 12-40 days
f) Living things produce waste.
ex. kidneys filter waste from your blood
2.Define organism:
Living things are often referred to as organisms. But it must have all six characteristics of living things in order to be called an organism.
- What are the two main ideas of the cell theory?
(a) All living things are composed of one or more cells.
(b) All new cells arise only from cells that already exist.
Section 1.3 – Plant and Animal Cells (page 10-13)
- State the difference between eukaryotic and prokaryotic cells.
Eukaryotic cells have a nuclear membrane. Prokaryotic cells have no nuclear membrane surrounding the nucleus and are one-celled organisms. - Animal Cell Structures – give the description and function for the following cell structures as seen through a compound light microscope:
Cell Structure / Description / Function
Nucleus
/ Control centre. / Directs all of the cell's activities.
Chromosomes
/ Found inside the nucleus and contain DNA or genetic information. / Holds the construction plans for the cell. Tells the cell what to become and what to do.
Cell Membrane
/ Thin wall surrounding the cell made from a double layer of fat molecules. / Holds the contents of the cell in place. Gatekeeper controlling movement of materials into and out of the cell.
Cytoplasm
/ The watery fluid which makes up most of the cell. / Allows materials to be transported quickly between the structures of the cell. Stores waste to be disposed of.
Vacuole
/ Small bubbles filled with fluid. / Used to store water and nutrients. Used to store waste. Used to move water and waste out of the cell.
Flagellum
/ Whip-like tail on the outside of some cells. / Helps the cell move around.
Cilia
/ Tiny hairs found on the outside of some cells. / Helps the cell to move. Helps to move the fluid around the cell.
- Draw Figure 2, page 11 in the space below.
- Plant Cell Structures - give the description and function for the following cell structures as seen through a compound light microscope:
Cell Structure / Description / Function
Vacuole
/ Much larger bubble inside the cell than animal vacuoles. / Filled with water and nutrients and waste. Nutrients feed cell; excess water and waste are eliminated through the cell wall.
Cell Wall
/ Outer shell. Some plant cells have 2 cell walls. / Protect and support the cell. Pores in the wall allow minerals, nutrients, water, and waste in and out.
Chloroplasts
/ Smaller bubbles inside the cell. / Food factories. Store chlorophyll and create their own food with chlorophyll, sun light, carbon dioxide, and water.
- List the similarities and differences between plant and animal cell structures.
SIMILARITIES: Both have a nucleus, cell membranes, chromosomes, cytoplasm, and vacuoles. DIFFERENCES: plants have cell walls, chloroplasts (make their own food through photosynthesis, vacuoles that are much bigger; some animal cells have flagellum and cilia to help the cell to move around with and to move materials close to the cell around. - Where in the cell do you find genetic information? In the chromosomes inside the nucleus
- Predict what might happen to a cell if the cell membrane was replaced by a plastic covering that prevented molecules from entering or leaving the cell. Why?
The cell would die. No nutrients or water allowed in and no waste allowed out would mean starvation and poisoning. - Cilia also function to remove dirt and debris. Where in the human body might you find cells with cilia? Explain your answer.
In the trachea and bronchial tubes to keep particles from entering your lungs.
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