2019 Cell Unit Test Review

What are the 3 parts of the Cell Theory?

1. All living things are made of cells. 2. Cells are the basic unit of structure and function of living things. (an organism can’t be smaller than a cell) 3. Cells can only come from other living cells.

Explain the structure and function of a unicellular organism (specialization).

A unicellular organism is made of one cell that is NOT specialized A unicellular organism is made of one cell that is NOT specialized. The one cell is able to support all of the needs of the organism.

What is an organelle?

Organelles are structures inside cells that have specific functions. Examples: nucleus, ribosomes, centrioles They are NOT alive. The smallest living unit is a cell.

Define multicellular organism, explain what types of cells they have, and how they are organized.

A multicellular organism is made up of several different cells that are specialized. The structure and function of the cells are different. A group of cells working together form tissues, which form organs, which form organ systems, which form an organism.

Define eukaryote and prokaryote.

Eukaryotes have cells that are larger, more complicated, contain a nucleus, and membrane-bound organelles. Prokaryotes have a single cell with a simple design (no nucleus) = bacteria.

Compare and contrast plant and animal cells.

large vacuole small vacuoles angular rounded shaped Plant Cell Animal Cell   outer layer = cell wall outer layer = cell membrane also has cell membrane chloroplasts large vacuole small vacuoles angular rounded shaped autotrophic heterotrophic

What is the difference between chlorophyll and chloroplasts?

Chloroplasts are organelles where photosynthesis occurs in autotrophic cells. Chloroplasts contain chlorophyll, which is the green photosynthetic pigment.

Identify the function of the following organelles: A. nucleus B. cell membrane C. vacuole D. chloroplast E. mitochondria F. cell wall

organelle function nucleus – controls cell’s activities B. cell membrane – controls what enters and leaves cell C. vacuole – “storage bins” D. chloroplast - site of photosynthesis (contain chlorophyll) E. mitochondria – produces energy F. cell wall - support for plant , fungi, and bacterial cells

Identify: nucleus, mitochondria, ribosome, cytoplasm, & outer layer

Identify: nucleus (8), mitochondria (2), ribosome (3), cytoplasm (7), & outer layer (cell membrane)

selectively permeable Explain what a selectively permeable (semi-permeable) cell membrane means.

A selectively permeable cell membrane determines what molecules are able to enter and leave the cell.

What is the difference between passive and active transport.

Passive transport is when molecules move from high to low concentration, without a cell needing to use energy. Active transport is when molecules move from low to high concentration, with a cell using energy to make it happen.

Define diffusion.

Diffusion is the movement of molecules from high to low concentration.

Define osmosis.

Osmosis is the diffusion (moves from high to low concentration) of water through a selectively permeable cell membrane.

Define homeostasis.

Homeostasis is the ability of a cell to maintain stable internal conditions or environment. This is accomplished by the cell membrane controlling what enters and leaves the cell.

Explain what is happening in the onion cells that are exposed to salt water.

Water is leaving the onion cells through the process of osmosis because the cells are exposed to salt water. Water moves from high concentration to low concentration. The cytoplasm and vacuoles lose water.

Why are cells so small?

Cell size is limited because cells need a large surface area to volume ratio. (They need a large amount of surface area to support their size.) Molecules must be able to travel quickly into and out of cells.

Write the chemical equation for photosynthesis Write the chemical equation for photosynthesis. Label the names of the molecules. Identify where it occurs in the cell.

occurs in chloroplasts sunlight 6 CO2 + 6 H2O C6H12O6 + 6 O2 carbon dioxide water glucose oxygen   occurs in chloroplasts carbon dioxide and water combine in the presence of sunlight to produce glucose and oxygen

Explain how a tree is able to gain so much mass.

The mass of a tree in primarily carbon that originates from the carbon dioxide gas that a plant takes in during the process of photosynthesis.

Explain how root hair cells are specialized cells.

Root hair cells increase the surface area for water absorption Root hair cells increase the surface area for water absorption. They have large vacuoles to store water. Water also flows into root cells through osmosis because of the salt in their vacuoles.

Explain the structure and function of stomata.

Stomata are opening in plant leaves through which carbon dioxide enter and oxygen exits. Plants will open and close stomata to conserve water and to prevent excess loss.

Write the chemical equation for cellular respiration Write the chemical equation for cellular respiration. Label the names of the molecules. Identify where it occurs in the cell.

C6H12O6 + 6 O2 6 CO2 + 6 H2O + ATP glucose oxygen carbon dioxide water energy occurs in the mitochondria glucose combines with oxygen to give an organism energy

Use a VENN diagram to compare/contrast photosynthesis and cellular respiration.

photosynthesis cellular respiration produces ATP (energy) from food produces carbon dioxide and water occurs in mitochondria autotrophs & heterotrophs produces: food oxygen occurs in chloroplasts needs sun autotrophs almost reverse processes; switches reactants and products

photosynthesis cellular respiration chloroplast 6CO2 + 6H2O sun C6H12O6 + 6O2 C6H12O6 + 6O2 6CO2 + 6H2O + ATP mitochondria