Download Nutrition and red blood cells

Name __________________________
Tuesday, 11-15-16
Packet # 2 - 10
7th Science - ________
AIM: Explain how specialized cells are the building blocks for
multicellular organisms.
Quote of the Day: “Practice doesn’t make perfect. Perfect practice
makes perfect.” - Cal Ripken, Sr., Baltimore Orioles Coach and Manager
Do Now - Read/annotate the text before answering the questions that follow:
Cell Specialization All organisms are composed of cells. Unicellular organisms are
composed of a single cell. Multicellular organisms are composed of many specialized
cells. Specialized cells differ in structure (size, shape...) and function (the role they
perform in the organism). The structural modifications (changes) that occur in a
specialized cell prepare it to do its job in the organism. An adult human is composed of
approximately 100 trillion cells and has over 200 different types of specialized cells. All
of these specialized cells do a very different, very specific job.
Examples of specialized cells are red blood cells (carry oxygen), skeletal muscle cells
(contract to allow movement of body parts) and sperm cells (male reproductive).
1. How many cells are in an adult human? 100 trillion
2. How many different types of specialized cells are in an adult human? 200
3. Give one example of a specialized cell. Red blood cells
Video, Discovery Education – Specialized Cells, 4:26. Take notes on each type of
specialized cell during the video. Be prepared to discuss.
Epidermis (Skin Cells)
Muscle Cells
Bone Cells
Nerve Cells (Neurons)
Red Blood Cells
White Blood Cells
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Work with a Partner – each group will be assigned one type of specialized cell. They
will read/annotate the text for their specific cell and be prepared to present the following
to the class:
 Draw the cell
 What does this specialized cell do?
 How does it do it? What is unique about this specialized cell?
1. Muscle Cells
A myocyte (also known as a muscle cell) is the type of cell found in muscle tissue.
Myocytes are long, tubular cells that develop from myoblasts to form muscles in a
process known as myogenesis. There are various specialized forms of
myocytes: cardiac, skeletal, and smooth muscle cells, with various properties.
The striated cells of cardiac and skeletal muscles are referred to as muscle fibers.
Cardiomyocytes are the muscle fibers that form the chambers of the heart, and have a
single central nucleus. Skeletal muscle fibers help support and move the body. Smooth
muscle cells control involuntary movements such as contractions in
the esophagus and stomach.
2. Nerve Cells (Neurons)
A neuron (also known as a[nerve cell) is an electrically excitable cell that processes and
transmits information through electrical and chemical signals. These signals between
neurons occur via synapses, specialized connections with other cells. Neurons can
connect to each other to form neural networks. Neurons are the core components of
the brain and spinal cord of the central nervous system (CNS), and of the ganglia of
the peripheral nervous system (PNS). Specialized types of neurons include: sensory
neurons which respond to touch, sound, light and all other stimuli affecting the cells of
the sensory organs that then send signals to the spinal cord and brain, motor neurons that
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receive signals from the brain and spinal cord to cause muscle contractions and
affect glandular outputs, and interneurons which connect neurons to other neurons within
the same region of the brain, or spinal cord in neural networks.
3. Red Blood Cells
Red blood cells play an important role in your health by carrying fresh oxygen
throughout the body.
Red blood cells are round with a flattish, indented center, like doughnuts without a
hole. Your healthcare provider can check on the size, shape, and health of your red
blood cells using tests, such as the complete blood count screening.
Hemoglobin is the protein inside red blood cells that carries oxygen. Red blood cells
also remove carbon dioxide from your body, transporting it to the lungs for you to
exhale.
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Red blood cells are made inside your bones, in the bone marrow. They typically live
for about 120 days, and then they die.
Nutrition and red blood cells
Foods rich in iron help you maintain healthy red blood cells. Vitamins are also
necessary to build healthy red blood cells. These include vitamin E, found in foods
such as dark green vegetables, nuts and seeds, mango, and avocados; vitamins B2,
B12, and B3, found in foods such as eggs, whole grains, and bananas; and folate,
available in fortified cereals, dried beans and lentils, orange juice, and green leafy
vegetables.
4. White Blood Cells
White blood cells are an important component of your blood system, which is also
made up of red blood cells, platelets, and plasma.
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Although your white blood cells account for only about 1% of your blood, their
impact is significant. White blood cells, also called leukocytes, are essential for
good health and protection against illness and disease.
Think of white blood cells as your immunity cells. In a sense, they are continually at
war. They flow through your bloodstream to battle viruses, bacteria, and other
foreign invaders that threaten your health. When your body is in distress and a
particular area is under attack, white blood cells rush in to help destroy the harmful
substance and prevent illness.
White blood cells are made inside the bone marrow and stored in your blood and
lymphatic tissues. Because some white blood cells have a short lifespan of one to
three days, your bone marrow is constantly making them.
5. Bone Cells
Bone cells, which are found within the bone tissue, make up the skeletons of vertebrates.
There are different types of bone tissue in a bone, made up of various types of bone cells:
there is the cortical bone, which is the compact tissue of the hard outer part (cortex) of the
bone; the cancellous bone, which is the spongy tissue inside of the compact cortex; and
the subchondral tissue, which is the smooth tissue at the end of each bone.Bone cells all
work together inside of the bones to help keep up the skeletal system. The bone cells do
many things for the skeletal system, such as the development of new bones and
continual bone remodeling (the maintenance of bones and the regulation of minerals in
the body). Types of bone cell include osteoclasts, which break down bone
tissue; osteoblasts, which build new bone tissue; osteocytes, which hold up the bone
together; and lining cells, which protect the bone.
There are four main categories of bone cells which include: 1. osteoclasts, which destroy
bones 2. osteoblasts, which build bones 3. osteocytes, which hold the bone together 4.
lining cells, which protect the bone.
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6. Xylem
Xylem
Xylem is an interesting part of a plant in that it is its "woody" material. One reason it is
"woody" is to provide support throughout the entire plant, as with a tree. One interesting
tidbit about xylem is that when you cut down a tree and look at the tree trunk's "rings",
you can see the old xylem tissue that encompassed the tree. Every xylem ring constitutes
a year that a tree was alive.
The primary role of xylem is to provide nutrients and water for a plant. A plant achieves
this by absorbing water and nutrients through the plant's roots, where it transports these
goods throughout the plant by xylem. Since xylem is connected throughout the plant by
its "vessels," it easily passes the nutrients and water quickly and efficiently like a human's
blood vessels.
It should be mentioned that xylem operates from the bottom up. This means that it starts
from the roots where it acquires water and nutrients. Xylem then "progresses" up
throughout the rest of the plant to regions such as the leaves and the branches.
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Xylem
7. Leaf Epidermis
You may have heard at some point that your skin is the largest organ in your body.
Besides being large, your skin is very important because it protects everything
underneath it from disease, temperature, and other physical damage that may occur.
Much like your skin, a plant has a tissue system, a group of cells that works together for
a very specific function, that forms the first line of defense against physical damage and
disease. This tissue system is called the dermal tissue system, and it is the plant's outer
protective coating.
The dermal system itself consists of a layer of tightly packed cells called the epidermis.
On most plant stems and leaves, the epidermis is covered with a waxy coating called
the cuticle, which helps prevent water loss through the epidermis.
Structure
Plant epidermis is unique because it is actually two different layers of cells: the upper
epidermis and the lower epidermis.
Sandwiched in between these two layers are two other important tissue systems - the
vascular tissue system and the ground tissue system. The vascular tissue
system provides water and nutrient transport from the roots to other parts of the plant.
The ground tissue system, also called the mesophyll, is specialized for photosynthesis,
the process by which the plant converts sunlight into usable chemical energy.
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Notes
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