Download B07 comparison of plant and animal cells

B07 comparison of plant and animal cells
Comparison of Plant and Animal Cells
April 01, 2011
http://www.teachersdomain.org/
organism
Cells vary widely in form and function, even within the same __________. The human body, for cells
example, is made up of about two hundred different types of specialized ______, ranging from foot­
long nerve cells to tiny, disk­shaped blood cells. At first glance these cells appear to have little in common other than the body or body part that houses them. For all their differences, though, animal
plant
different types of specialized cells have a lot in common. Even ______ and _______ cells have far more structural similarities than they have differences. Plant and animal cells have nearly all of the most important cell structures in common. For example, genetic
both plant and animal cells have a nucleus, which contains the cell's _________ material, or DNA. cytoplasm
Plant and animal cells also have some of the same organelles floating in the _________, the fluid­
Mitochondria
filled region between the cell membrane and the nucleus: ____________, the cell's "powerhouses," create energy through the process of aerobic respiration; ribosomes are responsible transports
proteins
for synthesizing _______; the endoplasmic reticulum stores and _________ proteins and other compounds within and outside the cell; Golgi bodies transform proteins into more complex molecules; and lysosomes contain as many as 40 different enzymes used to break down large molecules. Indeed, even under a microscope it is difficult to tell apart many plant organelles from the same organelles found in animals. Based on your homework on the organelles, label the following
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B07 comparison of plant and animal cells
April 01, 2011
Despite all their similarities, plant cells and animal cells differ in two important ways. First, plant chloroplasts
cells have structures called ____________, and animal cells don't. Chloroplasts are the green
structures that give leaves their ______ color and, more importantly, allow plants to acquire sun
animals
their energy from the ____ rather than from food, the primary source of energy for _______. Like ______________, chloroplasts convert energy from one form to another. However, this mitochondria
process, called photosynthesis, is in many ways the opposite of the mitochondria's oxygen
respiration
_______________ process. In ___________, food molecules are combined with ______ to respiration
photosynthesis,
produce energy and carbon dioxide. In ______________ chloroplasts use energy from the sun sugars
to convert carbon dioxide and water into food molecules like _______ and other carbohydrates. All cells have a cell membrane, a structural layer that gives the cell shape, while allowing molecules of various types to pass into and out of the cell. Unlike animal cells, however, plant cell wall
cell wall
cells have a _________ that surrounds the entire cell, including the membrane. The ________ provides plant cells with a protective covering and gives the plant the _______ it needs in order rigidity
cellulose
to stand up even under pressure from wind, rain, and snow. This wall is made of __________ and is intricately cross­linked with fibers of other carbohydrate molecules. This structural pattern also allows each cell to withstand the increased internal pressure from osmosis, when the plant absorbs water.
http://micro.magnet.fsu.edu/cells/plants/vacuole.html
Another differences is the size and function of the vacuole.
In mature plant cells, vacuoles tend to be very large and are extremely important in providing structural support, as well as serving functions such as storage, waste disposal, protection, and growth. Many plant cells have a large, single central vacuole that typically takes up most of the room in the cell (80 percent or more). Vacuoles in animal cells, however, tend to be much smaller, and are more commonly used to temporarily store materials or to transport substances.
The structural importance of the plant vacuole is related to its ability to control turgor pressure. Turgor pressure dictates the rigidity of the cell and is associated with the difference between the osmotic pressure inside and outside of the cell. Osmotic pressure is the pressure required to prevent fluid diffusing through a semipermeable membrane separating two solutions containing different concentrations of solute molecules. The response of plant cells to water is a prime example of the significance of turgor pressure. When a plant receives adequate amounts of water, the central vacuoles of its cells swell as the liquid collects within them, creating a high level of turgor pressure, which helps maintain the structural integrity of the plant, along with the support from the cell wall. In the absence of enough water, however, central vacuoles shrink and turgor pressure is reduced, compromising the plant's rigidity so that wilting takes place.
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B07 comparison of plant and animal cells
April 01, 2011
Homework Questions
1. Complete the following table on the similarities and difference of plant and animal cells
Feature
Plant Cell
Animal Cell
Differences
Structural Support
Vacuoles
Similarities Nucleus Present
Cytoplasm present
Cell membrane present
Vacuoles Present
2. Why don't animal cells need cell walls? 3. Why is it important that plant cells are different from animal cells?
4. What are the similarities and differences between cellular respiration and photosynthesis?
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B07 comparison of plant and animal cells
April 01, 2011
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B07 comparison of plant and animal cells
April 01, 2011
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B07 comparison of plant and animal cells
April 01, 2011
Fill in the blank Answers
Cells vary widely in form and function, even within the same organism. The human body, for example, is made up of about two hundred different types of specialized cells, ranging from foot­long nerve cells to tiny, disk­shaped blood cells. At first glance these cells appear to have little in common other than the body or body part that houses them. For all their differences, though, different types of specialized cells have a lot in common. Even plant and animal cells have far more structural similarities than they have differences. Plant and animal cells have nearly all of the most important cell structures in common. For example, both plant and animal cells have a nucleus, which contains the cell's genetic material, or DNA. Plant and animal cells also have some of the same organelles floating in the cytoplasm, the fluid­filled region between the cell membrane and the nucleus: Mitochondria, the cell's "powerhouses," create energy through the process of aerobic respiration; ribosomes are responsible for synthesizing proteins; the endoplasmic reticulum stores and transports proteins and other compounds within and outside the cell; Golgi bodies transform proteins into more complex molecules; and lysosomes contain as many as 40 different enzymes used to break down large molecules. Indeed, even under a microscope it is difficult to tell apart many plant organelles from the same organelles found in animals. Despite all their similarities, plant cells and animal cells differ in two important ways. First, plant cells have structures called chloroplasts, and animal cells don't. Chloroplasts are the structures that give leaves their green color and, more importantly, allow plants to acquire their energy from the sun rather than from food, the primary source of energy for animals. Like mitochondria, chloroplasts convert energy from one form to another. However, this process, called photosynthesis, is in many ways the opposite of the mitochondria's aerobic respiration process. In aerobic respiration, food molecules are combined with oxygen to produce energy and carbon dioxide. In photosynthesis, chloroplasts use energy from the sun to convert carbon dioxide and water into food molecules like sugars and other carbohydrates. All cells have a cell membrane, a structural layer that gives the cell shape, while allowing molecules of various types to pass into and out of the cell. Unlike animal cells, however, plant cells have a cell wall that surrounds the entire cell, including the membrane. The cell wall provides plant cells with a protective covering and gives the plant the rigidity it needs in order to stand up even under pressure from wind, rain, and snow. This wall is made of cellulose and is intricately cross­linked with fibers of other carbohydrate molecules. This structural pattern also allows each cell to withstand the increased internal pressure from osmosis, when the plant absorbs water.
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