BIO 1408 ~ CH 3
(VIDEO BURNING WOOD) What were the conclusions of this experiment?
- Cells have a high surface area to volume ratio. - Substances are able to move quickly into and out of cells if they are small. - Small cell size helps sustain all chemical reactions needed for life.
Which of the following are eukaryotic organisms?
- Fungi - Plants - Animals
Which of these are examples of a protein or lipid that originates with the endomembrane system?
- Hormones that assist in the regulation of body temperature - Proteins that are involved in cell membrane structure - Digestive enzymes that are used to break down incoming nutrients
Facts that support the endosymbiotic theory:
- Mitochondria and chloroplasts have their own DNA - Mitochondria and chloroplasts are surrounded by two membranes - Mitochondria are about the same size as most bacteria
Select all the following organelles that are found in all eukaryotic cells.
- Plasma Membrane - Cytoplasm - Endoplasmic Reticulum (ER) - Vacuole - Nucleolus - Mitochondria - Golgi Apparatus - Cytoskeleton - Ribosomes
Why is it beneficial for cells to be small?
- To quickly move waste products out of the cell - To allow sufficient nutrients to enter the cell
The cell theory states:
- all organisms are composed of cells. - cells are the basic unit of structure and function. - cells come from pre-existing cells.
What is an endosymbiont?
A microorganism that lives within another cell, performing specific functions for its host
Which scenario below most likely explains how the nucleus originated?
A portion of the plasma membrane was internalized so that it surrounded the DNA within a cell.
Classify the following characteristics to describe the differences between plant and animal cells.
ANIMAL CELLS: - Centrioles to help form basal bodies - Lysosomes to provide intracellular digestion - Plasma membrane to regulate the passage of molecules into and out of the cells. - Mitochondria to undergo respiration and provide energy PLANT CELLS: - Plasma membrane to regulate the passage of molecules into and out of the cell. - Mitochondria to undergo respiration and provide energy - Chloroplasts to undergo photosynthesis - Cell walls to provide structure and support - A large central vacuole for water storage
Fill in the blank:
After products leave the endoplasmic reticulum, they head to the GOLGI APPARATUS for further processing, modification, and repackaging.
Fill in the blank:
As cell size DECREASES, the rate of waste exchange increases.
The inner membrane of chloroplasts and mitochondria is likely derived from the cell membrane of the host.
FALSE
Classify each of the following traits based on the domain that is being described.
BACTERIA: - Abundant and diverse organisms that lack membrane bound organelles. - Contain cell walls consisting of peptidoglycan. - Some used by humans to synthesize chemicals and products. ARCHAEA: - Contain cell walls with unique lipids that help them to survive high heat, pH, and salinity. - Reside in extreme environments such as sulfur springs and thermal vents.
Complete the following paragraph to describe the surface-area-to-volume ratios for small, medium, and large cells.
Based on the graph, as surface area increases, volume INCREASES and the surface-area-to-volume-ratio DECREASES. This is because the VOLUME increases more quickly than the SURFACE AREA. In this manner, the SMALL cells are the most efficient because they have a LARGE surface area available for all the processes and reactions needed for a SMALL volume.
Complete the following paragraph:
Blue whales are approximately 25 METERS in length, roughly 25 times the size of a(n) HUMAN. Human eggs are approximately 150um in diameter. Frog eggs are approximately 1.5mm in diameter. Frog eggs are roughly 10 times the size of human eggs. The larger viruses are approximately 100nm in size and the larger plant cells are approximately 100um in size. The larger plant cells are roughly 1000 TIMES the size of viruses.
Categorize the following as structural/functional characteristics of either the chloroplasts or the mitochondria.
CHLOROPLASTS: - Not found in animal cells - Contain chlorophyll - Carry out photosynthesis - Ultimate source of food for all living things MITOCHONDRIA: - Found in plants and animal cells - Carry out cellular respiration - Abundant in human muscle cells
Decide which type of microscope is best for each of the following applications:
COMPOUND LIGHT MICROSCOPE: - Chloroplasts are photosynthetic structures found within plant cells that circulate around the cytoplasm of the cell through a process called cytoplasmic streaming. TEM: - The flu virus contains intrastructural details that relate to its pathogenicity. SEM: - Radiolarians are single celled protists that have unique and intricate mineral skeletons.
Classify each characteristic to describe each microscope.
COMPOUND LIGHT MICROSCOPE: - Often requires dye in order to see individual structures - Provides an internal view of the organisms - Uses light rays and a set of glass lenses to visualize and magnify objects SCANNING ELECTRON MICROSCOPE (SEM): - Provides external views of organisms - Uses electrons and electromagnetic lenses to visualize and magnify objects - Can provide a 3D view of objects TRANSMISSION ELECTRON MICROSCOPE (TEM): - Has the highest capabilities for magnifying images - Provides an internal view of the organisms - Best at making out individual details - Uses electrons and electromagnetic lenses to visualize and magnify objects
Match each specific antibiotic to the mechanism by which it disrupts the synthesis of peptidoglycan.
CYCLOSERINE: - Blocks peptide side chain formation BACITRACIN: - Inhibits the reuse of bactoprenol, which transports disaccharide pentapeptide precursors through the cell membrane VANCOMYCIN: - Prevents the formation of covalent bonds between adjacent glycan chains PENICILLIN: - Inhibits the transpeptidase in the cell that forms the covalent bonds between peptide side chains
The basic unit of life is a(n)
Cell
Complete the following conversions:
Chloroplasts are photosynthetic organelles that are approximately 1.5 um in length. How many nanometers is this? - 1500nm Human eggs are approximately 150 um. Frog eggs are approximately 1.5 mm. How much larger are frog eggs than human eggs? - 100x A human is approximately 0.87 meters in height. How many millimeters is this? - 870mm
(VIDEO BURNING WOOD) The purpose of this experiment was to:
Determine why cells are small.
An increase in cell size results in an increase in surface area to volume ratio.
FALSE
Different types of antibiotics all use the same mechanism for killing bacteria.
FALSE
Complete the following paragraph to describe how the endosymbiotic theory explains eukaryotic cell evolution.
Fossil evidence suggests that the first cells were PROKARYOTES, which leads scientists to believe that EUKARYOTES evolved from PROKARYOTES. During ENDOSYMBIOSIS, one cell takes up another. It is likely that through this process, the evolution of EUKARYOTES from PROKARYOTES occurred in stages. For instance, the invagination of the PLASMA MEMBRANE could explain several of the internal structures of EUKARYOTES, like the endoplasmic reticulum and Golgi apparatus. Mitochondria and chloroplasts may also have been acquired this way. If a "host" cell took up a smaller cell that could benefit it by producing ENERGY in the form of ATP or glucose, the two cells might have continued to live cooperatively.
(VIDEO BURNING WOOD) Which factor was being measured in the experiment?
How long it took the wood to completely burn
Eukaryotic cells are compartmentalized into structures known as:
Organelles
Both combustion and cellular respiration require?
Oxygen
Match the parts of the statements to make them correct.
Photosynthetic bacteria use pigments embedded in their membranes TO DERIVE ENERGY FROM THE SUN. Chloroplasts appear to have been derived from PHOTOSYNTHETIC BACTERIA. Mitochondria appear to have been derived from PURPLE BACTERIA. The mitochondria of cells today were once a type of bacteria that was able TO PRODUCE ENERGY IN THE FORM OF ATP.
One common structure found in both prokaryotic and eukaryotic cells is a(n)
Ribosomes
Place the following organelles of the endomembrane system in the order they are used in the synthesis, packaging, and the export of proteins.
Ribosomes on rough endoplasmic reticulum, transport vesicle, Golgi apparatus, secretory vesicle, plasma membrane
(VIDEO BURNING WOOD) Which factor was changed between each trial?
Size of wood pieces
Because plant cells contain both mitochondria and chloroplasts, but animal cells only contain mitochondria, it is thought that early cells gained mitochondria first, before chloroplasts.
TRUE
Both mitochondria and chloroplasts have their own circular DNA, similar to that of prokaryotes.
TRUE
Prokaryotic cells generally have a higher surface area to volume ratio than eukaryotic cells.
TRUE
In addition to the nucleus, which of the following organelles are also thought to have evolved from an invagination of the plasma membrane?
The Golgi apparatus and the endoplasmic reticulum are both believed to have evolved through an invagination of the plasma membrane.
How did early eukaryotic cells benefit from the aerobic bacteria that took up residence within them?
The aerobic bacteria metabolized sugars and generated large amounts of ATP.
How did early eukaryotic cells benefit from the photosynthetic bacteria that took up residence within them?
The aerobic bacteria were able to capture the sunlight and generate sugars from it.
Complete the following paragraph to describe the characteristics of the cell theory.
The term CELL was originally coined by the scientist Robert Hooke based on structures he observed in cork and studies previously done by VAN LEEUWENHOEK. Over the next 150 years, scientists such as Schwann further supported Hooke's statements by stating that ANIMALS are also composed of cells. His counterpart, Schleiden, stated that PLANTS are composed of cells. Rudolf Virchow later concluded that cells do not spontaneously appear but come from PRE-EXISTING cells. The findings of all of these scientists in part, have led to the present cell theory, which states that all ORGANISMS are composed of cells and all cells come from pre-existing cells. Today, the cell theory is an important, basic theory of BIOLOGY.
Why are the organelles within the endomembrane system interchangeable?
They are all comprised of phospholipid membranes.
The rough endoplasmic reticulum differs from the smooth endoplasmic reticulum in that:
They differ in that the rough endoplasmic reticulum contains ribosomes, while the smooth endoplasmic reticulum does not. They also differ because the rough endoplasmic reticulum is mostly involved in protein synthesis, while the smooth endoplasmic reticulum is mostly involved in the production of lipids and carbohydrates.
How do antibiotics kill bacteria without harming host cells?
They interfere with the synthesis of peptidoglycan, a unique portion of the cell membranes of bacteria that is essential for their survival.
(VIDEO BURNING WOOD) What was used to ignite the fire evenly?
Two eggs cartons
