Cells Test

Question 1

Differences Between Prokaryotic and Eukaryotic Cells (5)

Answer 1

Prokaryotic: No nucleus. No membrane-bound organelles. Division is binary fission. Small and unicellular. Have cell walls made of peptidoglycan.

Eukaryotic: Yes nucleus. Yes membrane-bound organelles. Division is mitosis. Larger unicellular or multicellular. Only fungi and plants have cell walls (made of chitin or cellulose).

Question 2

Similarities Between Prokaryotic and Eukaryotic Cells (5)

Answer 2

Cell membrane. Cytoplasm. Cytoskeleton. Ribosomes. Genetic Information (DNA or RNA).

Question 3

Differences Between Plant and Animal Cells (3 Organelles Plants. 3 Organelles Animals.)

Answer 3

Plant cells have chloroplasts, cell wall, and a large central vacuole. Animal cells have centrioles/centrosomes, lysosomes, and sometimes cilia/flagella.

Question 4

Cell Membrane (Plasma)

Answer 4

Animal, Plant, Prokaryote. Controls what goes in and out of the cell.

Question 5

Phospholipid Bilayer

Answer 5

Two layers of fats. The fats are phospholipids with hydrophilic heads and hydrophobic tails. Proteins embedded. Composed of many parts that move around freely.

Question 6

Cytoskeleton

Answer 6

Animal, Plant, Prokaryote. Give the cell shape. Can move organelles around. Provide structural support for animal cells (who don’t have a cell wall).

Question 7

Cytoplasm

Answer 7

Animal, Plant, Prokaryote. Holds everything in place. Provides a solution for chemical reactions to take place in.

Question 8

Nucleus

Answer 8

Animal, Plant. Protect the DNA that controls the activity of the cell.

Question 9

Nucleolus

Answer 9

Animal, Plant. Inside the nucleus. Make mRNA which make up ribosomes.

Question 10

Mitochondria

Answer 10

Animal, Plant. Structure: Where cellular respiration happens. Breaks down food to release energy. Powerhouse of the cell.

Question 11

Smooth Endoplasmic Reticulum

Answer 11

Animal, Plant. Job: Makes lipids (membranes). Destroys toxins (liver). Regulates calcium (muscles).

Question 12

Rough Endoplasmic Reticulum

Answer 12

Animal, Plant. Structure: Ribosomes on the surface. Hugs the nucleus. Job: Makes, transports, and modifies proteins.

Question 13

Ribosomes

Answer 13

Animal, Plant, Prokaryote. Make proteins!

Question 14

Golgi Apparatus

Answer 14

Animal, Plant. Gets vesicles of protein from ER. Vesicles are like mini-carts that transport proteins around the cell. Processes, sorts, and ships protein where needed.

Question 15

Vacuoles

Answer 15

Animal, Plant. Structure: Small and numerous in animal cells. One large central vacuole in plant cells. Job: Storage (water, nutrients, waste, etc.)

Question 16

Lysosomes

Answer 16

Animal. Structure: Contain enzymes. Job: Breakdown dead stuff (food, bacteria, old parts of cells, etc.). Can do programmed cell death (apoptosis).

Question 17

Cilia and Flagella

Answer 17

Animal/Prokaryote. Structure: Cilia - shorter, more numerous, like tiny oars. Flagella - longer, fewer. Job: Cilia - Move fluid across the cell surface. Flagella - move entire cell. NOT in all cells!

Question 18

Centrioles/Centrosomes

Answer 18

Animal. Appear during cell division (mitosis/meiosis). Help cells divide by pulling chromosomes apart.

Question 19

Chloroplasts

Answer 19

Plant. Where photosynthesis happens. Converts energy from sun to energy in sugar.

Question 20

Cell Wall

Answer 20

Plant, Prokaryote. Protect and maintain shape.

Question 21

Central Vacuole

Answer 21

Plant. Structure: One massive central structure. Job: Storage center.

Question 22

Facilitated Diffusion

Answer 22

A transport protein acts as a protein channel to help (facilitate) the diffusion of molecules that normally couldn’t pass across the cell membrane. Molecules move down a concentration gradient, from high to low concentration. Glucose and Sodium.

Question 23

Diffusion

Answer 23

The spreading out of molecules across a membrane until they are equally concentrated on both sides of the membrane. Molecules move down a concentration gradient, from high to low concentration. Oxygen and Carbon Dioxide.

Question 24

Osmosis

Answer 24

The diffusion of water across the cell membrane. Water molecules move down a concentration gradient, from high to low concentration.

Question 25

Endocytosis

Answer 25

A cell uses energy to important large amounts of materials INTO the cell using a vesicle.

Question 26

Phagocytosis

Answer 26

Cell “eating”. Cell engulfs solids into vesicles and digests them.

Question 27

Pinocytosis

Answer 27

Cell “drinking”. Cell engulfs liquids into vesicles and digests them.

Question 28

Receptor-Mediated Endocytosis

Answer 28

Particles are taken into a cell by binding to receptors.

Question 29

Exocytosis

Answer 29

A cell uses energy to export large amounts of materials OUT of the cell using a vesicle.

Question 30

Active Transport

Answer 30

Not all substances can move freely into or out of a cell. Some molecules have to be moved against the concentration gradient, from low to high concentration using ATP. Other substances are too big to move through a protein channel, and have to be enveloped or excreted from the cell.

Question 31

Hypertonic

Answer 31

Higher concentration of solutes within the cell compared to the outside environment. Water will move out the cell, down its concentration gradient. The cell shrivels (known as plasmolysis).

Question 32

Hypotonic

Answer 32

Lower concentration of solutes within the cell compared to the outside environment. Water will move into the cell, down its concentration gradient. The cell swells.

Question 33

Isotonic Solutions

Answer 33

Identical water concentrations to what is found in a cell’s cytoplasm. The cell stays the same.

Question 34

Membrane Structure

Answer 34

The cell membrane is made of phospholipids with phosphate heads and 2 fatty acid chain tails. Arranged in a bilayer: Polar heads are hydrophilic. Nonpolar tails are hydrophobic. The cell membrane is selectively permeable.

Question 35

Homeostasis

Answer 35

The need of an organism to maintain and regulate constant or stable internal conditions. Much of homeostasis is maintained by the cell membrane controlling movement of things in and out of the cell.

Question 36

What is the cell cycle? What is its purpose?

Answer 36

A repeated pattern of growth, DNA duplication, and cell division that occurs in eukaryotic cells. Three purposes: growth, repair, and reproduction.

Question 37

What are the different parts of the cell cycle?

Answer 37

G1 (Gap/Growth 1): The cell grows and makes proteins.
S (Synthesis): Chromosomes replicate.
G2 (Gap/Growth 2): Cells continue to grow and make proteins.
Mitosis: Cells divide.

Question 38

Which parts of the cell cycle are a part of interphase?

Answer 38

G1, S, G2

Question 39

What is Mitosis?

Answer 39

Cell division. One cell becomes two identical cells.

Question 40

What happens during mitosis?

Answer 40

Prophase: Chromosome copies condense and are visible as sister chromatids. Nuclear membrane breaks down. Spindle fibers form out of centrioles.
Metaphase: Chromosomes line up in the middle of the cell. Spindle fibers connect to the centromere of each sister chromatid.
Anaphase: Sister chromatids separate, becoming individual chromosomes as chromatids move to opposite ends of the cell.
Telophase: Nucleus reforms. Chromosomes start to look like chromatin again (threadlike). Spindle fibers break down and dissolve.
Cytokinesis: Cytoplasm pinches in half, forming two cells.

Question 41

Cancer and the Cell Cycle

Answer 41

Cancer is uncontrolled cell division. Cancer cells divide much more frequently than healthy cells, causing tumors to be formed. It’s caused when regulation of the cell cycle breaks down.

Question 42

Tumor

Answer 42

Clumps of cells that divide uncontrollably. Two types: malignant and benign.

Question 43

What organisms perform the cell cycle? What is the end result of the cell cycle?

Answer 43

Cells from all eukaryotic organisms perform this cell cycle. The cell cycle ends with mitosis, which produces two daughter cells that are genetically identical to the parent cell. However, since the cell cycle is a cycle, cells will keep going through the phases for a while.

Question 44

What are the checkpoints of the cell cycle?

Answer 44

G1 Checkpoint: Checks for nutrients, growth factors, DNA damage. It decides if the cell should divide, delay division, or enter G0 resting phase.
G2 Checkpoint: Checks for cell size and DNA replication. If the cell is prepared, it triggers the start of Mitosis.
Mitosis Checkpoint: Checks for chromosome spindle attachment. Occurs during metaphase and triggers the exit of mitosis and cytokinesis and the beginning of G1.

Question 45

What can go wrong with the cell cycle (cancer)? Detail a specific example of what could happen to cells in a cancer scenario.

Answer 45

There are many things that can go wrong with the cell cycle that result in cancer, including abnormal or damaged genes. Gene p53 plays a key role in G phase by monitoring DNA and making sure it has been duplicated correctly. p53 will repair damaged DNA if it can or will trigger the destruction of the cell if it’s too badly damaged. If p53 is not working correctly, cells can begin to divide with broken or altered DNA and can lead to cancerous cells.

Question 46

What is the cell cycle? What organisms perform the cell cycle? What is the purpose of the cell cycle? What is the end result of the cycle?

Answer 46

A repeated pattern of growth, DNA duplication, and cell division that occurs in eukaryotic cells. Cells from all eukaryotic organisms perform this cell cycle. Three purposes: growth, repair, and reproduction. The cell cycle ends with mitosis, which produces two daughter cells that are genetically identical to the parent cell. However, since the cell cycle is a cycle, cells will keep going through the phases for a while.