Unit 3A Pt1 - Cells and Body Systems

Unit 3A Part 1 -
Cells & Body Systems

Diffusion is the movement of the molecules of a substance from where they are more concentrated to where they are less concentrated.

​​Diffusion

Another form of passive transport, osmosis, is the diffusion of water across a selectively permeable membrane.​

​​Osmosis

Multiple Choice

3.2 - Osmosis is a form of passive transport. Which defines osmosis?

• the movement of water across a semipermeable membrane up a concentration gradient form low to high, using energy

• the movement of water across a semipermeable membrane down a concentration gradient from high to low using energy

• the movement of water across a semipermeable membrane up a concentration gradient form low to high, using no energy

• the movement of water across a semipermeable membrane down a concentration gradient from high to low, using energy

•Both diffusion and facilitated diffusion are forms of passive transport because the cell does not use any energy to move the substances.

​​No ATP Energy Required

​

•Using energy to move molecules across a membrane is called active transport.

​​ATP Energy Required

​•In exocytosis, a vesicle fuses with the plasma membrane and spills its contents outside the cell.

​​Exocytosis

•In the reverse process, endocytosis, vesicle bud inward from the plasma membrane and carry materials into the cell.

​​Endocytosis

Multiple Choice

3.2 - Endocytosis and exocytosis are forms of active transport, What is active transport?

• the movement of molecules down a concentration gradient from high to low, using no energy

• the movement of molecules up a concentration gradient from low to high, using energy

• the movement of molecules down a concentration gradient from high to low, using energy

• the movement of molecules up a concentration gradient form low to high, using no energy

Multiple Choice

3.2 - Cells dispose of large waste molecules through a process called

• diffusion.

• endocytosis.

• osmosis.

• exocytosis.

•A hypertonic solution has a higher concentration of solute, such as sugar, and a lower concentration of water than another solution.

​​Hypertonic

•The solutions are then isotonic, meaning that they have the same concentration of solute.

​​Isotonic

​•A hypotonic solution has a lower concentration of solute (sugar) and a higher concentration of water.

​​Hypotonic

Multiple Choice

3.2 - What does it mean for an environment to be isotonic?

• The concentration of solute is greater in the environment than inside the cell.

• The concentration of solute in the environment is different from the concentration inside the cell.

• The concentration of solute in the environment and the concentration inside the cell are at equilibrium.

• The concentration of solute is greater inside the cell than in the environment.

Multiple Choice

3.2 - A cell is dropped into a saltwater solution and shrivels up. You infer that, compared to the cell, the type of saltwater solution is

• hypertonic.

• hypotonic.

• isotonic.

• tonic.

•Rough ER has ribosomes attached to it.

•Smooth ER does not have ribosomes.

​•Enzymes built into the smooth ER perform many different functions, such as building lipid molecules and producing hormones.

​​2 Types of ER

•Some products made in the ER travel in vesicles to the Golgi apparatus, an organelle that modifies, stores, and sends proteins and other chemicals to their next destinations. 

•The finished products move by vesicles to specific targets within the cell or leave the cell by exocytosis.

Multiple Choice

3.3 -Which of the following correctly shows the sequence of organelles a protein would take if it were being exported from the cell?

• Smooth ER →→ Vesicle →→ Golgi apparatus →→ Rough ER →→ Vesicle →→ Nucleus

• Ribosome →→ Rough ER →→ Vesicle →→ Golgi Apparatus →→ Vesicle →→ Cell Membrane

• Ribosome →→ Vesicle →→ Rough ER →→ Vesicle →→ Golgi Apparatus →→ Cell Membrane

• Ribosome →→ Smooth ER →→ Vesicle →→ Cell Membrane →→ Vesicle →→ Rough ER

Multiple Choice

3.3 - The endomembrane system is a collection of membrane-bound organelles in eukaryotic cells that handles the production and processing of proteins that will be used in organelles or exported to the outside of the cell.  The rough endoplasmic reticulum, Golgi apparatus, and smooth endoplasmic reticulum all have parts to play in this system.  These functions are __________, respectively.

Identify the answer choice that correctly fills in the blank in the above passage.

• DNA packaging, DNA making, and DNA storing

• DNA making, DNA packaging, and DNA storing

• protein packaging, protein making, and lipid production

• protein making, protein packaging, and lipid production

Multiple Choice

3.3 - What would happen to a cell that lacked smooth endoplasmic reticulum?

• It would not be able to make lipids.

• It would not be able to replicate DNA.

• It would not be able to produce tRNA.

• Its cell membrane would be impermeable.

•Ribosomes are clusters of proteins and nucleic acids that build new proteins.

•Ribosomes in the cytoplasm make proteins that remain in the cytoplasm.

•Ribosomes attached to the endoplasmic reticulum make proteins that move out of the cell.

Ribosomes

​

Multiple Choice

3.3 - In which part of the cell do ribosomes perform protein synthesis?

• nucleus

• lysosome

• vacuole

• cytoplasm

Multiple Choice

3.3 - If the sequence of bases on the mRNA codon is AUU, what would be the sequence of bases on the opposite strand assembled by the tRNA?

• UUA

• UAA

• TAA

• ATT

​ •The cytoplasm also contains lysosomes, membrane-bound sacs that contain digestive enzymes that breakdown large molecules. 

•Lysosomes destroy harmful bacteria and break down damaged organelles.

​​Lysosomes

Multiple Choice

3.4 - Why are lysosomes important to the health of cells?

• They break down worn-out cell parts that are no longer needed.

• They allow cell organelles to move freely through the cell as needed.

• They move proteins around the cell.

• They create cell boundaries and make cells rigid.

​•Unlike animal cells, many plant cells have chloroplasts, organelles in which photosynthesis occurs.

•Plant cells also have a strong outer cell wall that protects the plant cell and maintains its shape.​

​​Plant Cells

Multiple Choice

3.4 - Which of the following organelles provide structure and rigidity to a plant cell?

• cell membrane

• ribosome

• cell wall

• chloroplast

Multiple Choice

3.4 - What would happen to a plant if the chloroplasts in its cells became damaged?

• The plant would be unable to make prorotein.

• The plant would be unable to reproduce.

• The plant would not have rigid structure.

• The plant would not make glucose and oxygen.

Multiple Choice

3.4 - Using your understanding of the function of chloroplasts and specialized cells, infer why plant root cells lack chloroplasts.

• Roots are underground and are not exposed to sunlight.

• Root cells have two central vacuoles.

• Roots require fewer nutrients.

• Root cells have many mitochondria.

•Prokaryotic cells, such as bacteria, do not have a nucleus and lack most other organelles.

​​Eukaryotic

​

​ •Eukaryotic cells, such as plant and animal cells, have a nucleus enclosed by a membrane, as well as other organelles with membranes.​

​​Prokaryotic

​

Multiple Choice

3.4 - What is the main difference between prokaryotic and eukaryotic cells?

• Prokaryotes use RNA instead of DNA.

• Prokaryotes lack a cell membrane on the outside.

• Prokaryotes lack ribosomes to make proteins.

• Prokaryotes lack membrane-bound organelles.

Multiple Choice

3.5 - In the model that you are going to build of the respiratory system, what structures will the straws represent?

• the chest cavity and ribs

• the lungs

• the diaphragm

• the bronchi and trachea

Multiple Choice

3.6 - Which system comprises of skin, hair, and other parts of the outermost layer of the body?

• nervous system

• lymphatic system

• endocrine system

• integumentary system