Download Structures in Cells – Section Review Questions Answers

Structures in Cells – Section Review Questions Answers
1. All living cells must obtain food and energy, convert energy from an external source into a form that the cell can
use, construct and maintain the molecules that make up cell structures, carry out chemical reactions, eliminate
wastes, reproduce and keep records of how to build structures.
2. 5 cell parts that are similar to a community
1. The nucleus – like the premier (comes up with the plans for the city)
2. The Golgi bodies – like purolator (send packages throughout the cell)
3. The lysosomes – garbage clean up
4. The cell membrane – like the police (controls what enters and leaves)
5. Microtubules – city streets for vesicles (cars) to travel along.
3. Plant cells
> Contain a cell wall NOT a cell membrane
> Have a central vacuole where animal cells have many small vacuoles
> Contain the “plastid family” the chloroplasts, the leukoplasts, the chromoplasts.
4. Many of the products made by the cell are intended for use in other places in the body. It would be harmful to the cell
to have materials made in the ER shared with the entire cell, so instead the ER makes vesicles or little bundles that keep
the contents separate from the rest of the cell. The Golgi apparatus is then able to accept the ER vesicles and makes its
own transport vesicles (by pinching off some of the Golgi body) that then ship the hormone out of the cell to the cell
membrane where it travels to other cells. Some examples of materials that are kept separate from the rest of the cell
include insulin and testosterone.
5. Folded cell structures can be found in the endoplasmic reticulum, the mitochondria and the Golgi bodies. The
increased surface area allows many chemical reactions to occur in a small space.
6. Eukaryotic cells contain a nucleus and prokaryotic cells contain a nucleoid (an area of condensed DNA material).
Eukaryotic cells are also far more sophisticated and contain many membrane bound organelles. Each organelle is highly
specific and has a particular function inside of the cell.
7. A – Nuclear Pores
B – DNA/chromatin
C – Nucleus
E – Endoplasmic Reticulum (both smooth and rough)
F- Peroxisome
H – Vacuole
I – Golgi apparatus (Golgi bodies)
J – Cell membrane
L – Cytoskeleton (microtubules and microfilaments)
M – Lysosome
O – Centrosome
P – Free floating Ribosome (also found on the RER)
D – Nucleolus
G – Cytoplasm
K- Vesicle
N – Mitochondria
8. Peroxisomes are very similar to lysosomes and contain strong enzymes, they are formed in the cytoplasm. Most
commonly found in the liver, kidney and brain cells as their main function is to break down long chain fatty acids and
detoxify alcohol.
9. The liver is a VERY large organ. Each cell contains many mitochondria that are responsible for making energy out of
food. Each liver cell would need to be 1 mm long if the mitochondria were arranged side by side.
10. Mrs. LeBlanc cell – must contain chlorophyll (in the chloroplast as that is what is responsible for performing
photosynthesis), a mitochondria (to make energy when the sun isn’t shining), and should have a flagella for swimming in
water!
11. a. All bacteria cells contain a cell wall, without a cell wall the bacteria cells can’t survive. When you take an anti-biotic
you take a medication that affects the synthesis of the peptidoglycan layer (an important part of the cell wall). Most
anti-biotics also block the cells ability to divide via binary synthesis, slowing bacteria reproduction, enabling health.
11. b. Most anti-biotics are very safe, but it is important to note that your body does require some bacteria to help you
thrive (think Activia yogurt). When your take antibiotics for a prolonged period of time, gram-positive bacteria is
affected, the natural bacteria that lives inside of your intestinal tract, your vagina, and mouth can become disurbed. It is
very common for women who take antibiotics to develop yeast infections in the mouth, and vagina due to this
imbalance. It is also very likely that prolonged exposure to antibiotics will also cause you to have an upset stomach
(common to both men and women) as a result of the disruption of the natural balance inside your body.
12. a. Fluorescence microscopy really enabled scientists to see the parts of the cytoskeleton. By inserting a dye with a
UV marker into the cell, a stained specimen can be viewed through UV filters.
12. b. Animal cells contain a fluid cell membrane which is very flexible. Unlike the cell wall, found in plants, the animal
cell requires a cytoskeleton to provide structure and support.
12. c. Prokaryotic cells are primitive, they have been around for many years. Because they are considered to be the “first
cells” they perform simple functions. Although they are able to carry out photosynthesis, they don’t have lysosomes,
they contain no folded membranes (limited surface area) so they are limited with the amount of chemical reactions
they can perform. It is important to note that although they have limited structure, size and function, the prokaryotic
cell still works efficiently to meet their needs using a smaller number of chemical reactions than eukaryotic cells.
13. Peroxisomes contain strong enzymes, and are very common in the liver. I would not expect to find peroxisomes
inside a red blood cell as the blood cell lacks a nucleus and most animal cell organelles.
14. The lysosome is responsible for recycling matter. They contain digestive enzymes that break down the structural
molecules or larger structures, like bacterium or worn-out organelles. The lysosome recycles cell matter so that the cell
doesn’t need to re-build all the organelle parts from scratch. This speedy process of recycling, saves the cell energy and
ensures that there is a constant supply of working organelles inside each cell.
15. Both the chloroplast and the mitochondrion provide energy to the cell. They are both surrounded by a double
membrane with inner folds or stacks that serve to increase the surface area for chemical reactions. Both the
mitochondrion and the chloroplast contain their own DNA!!! We will soon learn that both of these organelles were once
thought to have lived on their own as primitive prokaryotes, but thanks to the endosymbiotic theory, they have become
part of the eukaryotic cell.
16. Each nucleus contains and area of chromatin, called a nucleolus. The nucleolus is dedicated to producing the
chemical compounds used to construct the many ribosomes required by the cell. Without the nucleolus, there would be
no ribosomes, which means that protein synthesis (protein building) would be unable to occur.
17. Answers will vary. I have chosen the nucleus, the ribosome, mitochondria/chloroplast. I selected the nucleus as it
contains all of the DNA (blueprints) for the cell. The ribosome, as it is responsible for reading the RNA tag that leaves the
nuclear pores and contains the instructions for the proteins that need to be built in the cell. My final selection is the
mitochondrion/chloroplast in the cell because of the ability to convert food stuff into cell energy.
18. The development of the microscope enabled cells to be viewed and this allowed for the development of the cell
theory. Along with advances in microscopy so came greater understanding of cells, there organelles and cellular
processes. Our increased understanding into cellular biology is due to advances in microscope development. With
continued technological advances comes greater understanding.
19. William Harvey – (1578-1657) maggot come from eggs you fools! First to claim that abiogenesis is wrong.
Robert Hooke - (1635-1703) examines cork “cells”
Antony van Leeuwenhoek (1632-1723) better microscopes, animalcules, plaque on teeth
Francesco Redi (1629- 1697) meat that is covered with a cloth doesn’t develop maggots.
Lazzaro Spallanzani (1729-1799) fixes Needham’s boiled broth experiment and boils the broth longer and discovers
that nothing grows in the broth that is boiled, put in a clean container and covered.
Robert Brown (1773-1858) discovers the nucleus
Schleiden and Schwann (1810-1882) – “all plants are made of cells” “cells are organisms, and entire animals and
plants are collectives of these organisms”.
Alexander Henrich (1805-1877) – “the cell is the basic unit of life”
Jugo von Mohl (1805-1872) – cells have a flexible cell membrane
William Perkin (1838-1907) – develop cell dyes for staining organisms.
Ruldolph Virchow (1821-1902) – “Cells are the last link in a great chain [that forms] tissues, organs, systems, and
individuals…Throughout the whole series of living forms…there rules an eternal law of continuous development.”
Louis Pasteur (1822-1895) – disproves spontaneous generation once and for all. Shows that only from microorganisms can others appear.
20. Mostly scientists were limited by glass making techniques which didn’t improve until the nineteenth century. The
19th century also saw the competition of many English manufactures to compete to produce the “best” microscope.
During the 19th century, support for and interest in science was very high. Public lectures were popular. English scientist
writter, Jane Haldimand designed textbooks to help start the chatter amongst young people about cells.