2. Learning Competencies
1.explain the postulates of the cell theory;
2.describe the structure and function of major and subcellular organelles;
3.distinguish prokaryotic and eukaryotic cells according to their
distinguishing features;
4.classify different cell types (plant/animal tissues) and specify the
function(s) of each ; and
5.describe some cell modifications that lead to adaptation to carry out
specialized functions (e.g., microvilli, root hair).
5. Anton Van Leeuwenhoek
• He had great skill in
crafting lenses. Despite
the limitations of his
now-ancient lenses, he
observed the
movements of protists
and sperm, which he
collectively termed
“animacules”
7. Anton Van Leeuwenhoek
• Leeuwenhoek discovered in 1676 the bacteria
by observing on the plaque between his own
teeth and repeated this observations on 2
ladies and on two (2) old men who had never
cleaned their teeth in their lives. He gained
much of his inspiration from reading Hooke’s
Micrographia.
8. Robert Hooke
• He coined the term
“cell” for the box-like
structures he observed
when viewing cork tissue
through a lens.
9. Robert Hooke
• He used to look at dead cells. He prepared
a thin section of cork for viewing. What he
saw was the remaining cell wall.
10. Matthias Schleiden & Theodor Schwann
• They were
studying tissues
and proposed
the unified cell
theory. They
believed that all
living things are
composed of one
or more cells and
cell is the basic
unit of life.
11. Conclusions by Schwann
• The cell is the unit of structure, physiology,
and organization in living things.
• The cell retains a dual existence as a
distinct entity and a building block in the
construction of organisms.
• Cells form by free-cell formation, similar to
the formation of crystals (spontaneous
generation).
12. Rudolf Virchow
He is a German physician
who found that cells
divide to form new cells.
He concluded that
“omnis cellula e cellula”
or cells come from pre-
existing cells.
13. Cell Theory
1. All living things are structurally made
up of cells.
2. The cell is the fundamental unit of
life.
3. Cells come from the existing cells.
14. Timeline
1665
• Robert Hooke coined the term “cell” for the box-like
structures using cork tissue..
1676
• Anton Van Leeuwenhoek discovered the animacules
1838-39
• Matthias Schleiden and Theodor Schwann proposed
the cell theory.
1858
• Rudolf Virchow concluded that all cells come from
pre-existing cells..
18. Nucleus
• It is the control center
or brain of the cell. It
regulates organelle
activity within the cell
and houses the genetic
material of a cell. It
contains blueprint of
life which holds genetic
information for each
cell. It also directs the
production of proteins.
19. Cytoplasm
• This houses the cell
organelles. It is the site
where most cellular
activities occur. It is a
jelly like substance
within the cell which
contains various
enzymes and nutrients
that the cell needs.
20. Cell membrane
• It controls what comes in and out. This acts as a
barrier between the cytoplasm and the outside
environment of the cell. It is made up of lipid
bilayer.
22. Mitochondria
• This is the
powerhouse of the
cell. It takes in
nutrients, breaks them
down, and creates
energy for the cell. It is
the site for cellular
respiration. If the cell
is not getting enough
energy to survive,
more mitochondria
can be created.
24. Golgi Apparatus
• It is the main protein
packaging system of
cell. It modifies
proteins from
ribosomes and ships
them to their
destination within the
cell. It also acts as a
warehouse of the cell.
26. Cytoskeleton
• It maintains the cell’s
shape. It aids in cell
movement such as
flagella and cilia. It is
also responsible for
maintaining other
organelle’s position
within the cell.
29. Lysosome
• It functions as the
digestive organelle.
It breaks down food
and other
substances within
the cell and also
works to destroy
old organelles
30. Cell walls
• They are tough,
usually flexible but
sometimes fairly rigid
layer that surrounds
the plant cell. It
provides the cells with
structural support and
protection and also
acts as a filtering
mechanism.
31. Chloroplast
• It is an elongated or
disc-shaped organelle
containing chlorophyll
which captures light
energy to make
organic molecules in a
complex set of
processes called
photosynthesis.
32. Vacuole
• They are essentially
enclosed
compartments which
are filled with water
containing inorganic
and organic molecules
including enzymes in
solution. It used in
homeostasis.
33. Centrioles
• They are a minute
cylindrical
organelle near the
nucleus in animal
cells, occurring in
pairs and involved
in the development
of spindle fibers in
cell division.
34. Activity 1: Role Playing
• Act the role and functions of the cell’s
main part and its organelles.
Category 10 8 6 4
Believability
Clarity of Line
Body
Language
Facial
Expression
Accuracy of
content
Total score: 50
36. Activity 2: Comparing cells:
Prokaryotic vs. Eukaryotic cell
Task: Answer the table below together with your group mates.
Objective: Distinguish prokaryotic and Eukaryotic cell
Parts of the Cell Eukaryotic cell Prokaryotic cell
Organisms (at least five)
Cell wall
Centrioles
Cilia/flagella
Golgi body
Lysosomes
Peroxisomes
Nucleus
Plasma membrane
Chromosomes
Ribosomes
Endoplasmic reticulum
37. Comparison of Prokaryotic and Eukaryotic cell
Characterisitics Prokaryotic cell Eukaryotic cell
Organisms Bacteria and cyanobacteria fungi, plants, and animals
Nuclear membrane Absent Present
DNA Loop of DNA in the
cytoplasm
Thin, very long DNA
organized into chromosomes
in nucleus
RNA and protein Both synthesized in the same
compartment
RNA synthesized in the
nucleus; protein synthesized
in the cytoplasm
Cytoplasm No cytoskeleton; very few
organelles present
Cytoskeleton present; many
organelles present
Cellular organization Mainly unicellular Mainly multicellular with
differentiation of cells
Cell size Generally 1 to 10
micrometer in linear
dimension
Generally 10 to 100
micrometer in linear
dimension
38.
39.
40. Activity 2: Comparing cells:
Prokaryotic vs. Eukaryotic cell
Guide Questions:
1. What cellular structures do both prokaryotic and
eukaryotic cells have in common?
2. What organelles do eukaryotic cells have that are not
found in prokaryotic cells?
3. In terms of physical features (e.g., size and shape), how
do these two types of cells differ?
4. Are all prokaryotes unicellular? Can they be
multicellular?
5. Give other examples of single-celled eukaryotic
organisms.
41. Activity 3: Experiment Time
Title: Cheek’s cell and Onion’s skin cell
General Task: Draw the physical features
of cells you see under the microscope.
Objectives: identify the main parts of the
eukaryotic cell both plant (onion) and
animal (human).
43. Plant tissues
A tissue is a group of cells that performs
essentially the same function. Tissues in
plants are classified as follows:
1. Meristematic tissues – tissues primarily
concerned with formation of new cells by
division.
2. Permanent tissues – tissues that cease to
divide, having gained new parts or lost
old ones to perform specialized
permanent functions.
44. Meristematic tissues
1. Apical meristem – a group of meristematic cells
found at the tips of the plant, whose division
contributes to an increase in height or length of
the main axis of the plant.
2. Lateral meristem – a group of actively dividing
cells occupying a lateral position, parallel with
the sides of stems and roots, increase in width
and girth.
3. Intercalary meristem – derived from the apical
meristem but continuing meristematic activity at
some distance from the apical meristem.
47. Did you know that we can determine the age
of the tree using the secondary xylem!
48. Permanent tissues
1.Dermal tissue – outer protective covering tissue of the
plant that includes the epidermis and the periderm.
2.Vascular tissue – the conducting tissue of the plant
which functions for food, water and mineral distribution
in the plant body. (e.g. phloem and xylem)
3.Fundamental tissue – the entire complex of ground
tissue, composed of the tissues comprising the cortex
and the pith consisting of fundamental cell types
namely parenchyma tissue, collenchyma tissue, and
sclerenchyma tissue.
Dog & rabbit sperm cell
The person with the dubious honor of being the first to study sperm in detail was Anton van Leeuwenhoek, a Dutchman who developed the early compound microscope. Van Leeuwenhoek first used his new tool to examine more chaste subjects such as bee stingers, human lice and lake water in the mid-1670s.
Colleagues urged him to turn his lens to semen. But he worried it would be indecent to write about semen and intercourse, and so he stalled. Finally, in 1677, he gave in. Examining his own ejaculate, he was immediately struck by the tiny “animalcules” he found wriggling inside.
Hesitant to even share his findings with colleagues—let alone get a wriggler tattooed on his arm—van Leeuwenhoek hesitantly wrote to the Royal Society of London about his discovery in 1677. “If your Lordship should consider that these observations may disgust or scandalise the learned, I earnestly beg your Lordship to regard them as private and to publish or destroy them as your Lordship sees fit.”
Read more: https://www.smithsonianmag.com/science-nature/scientists-finally-unravel-mysteries-sperm-180963578/#uzfJdJfz3uyPHjIO.99Give the gift of Smithsonian magazine for only $12! http://bit.ly/1cGUiGvFollow us: @SmithsonianMag on Twitter
The Long, Winding Tale of Sperm Science
…and why it’s finally headed in the right direction
By Laura Poppick
SMITHSONIAN.COM JUNE 7, 2017
416060331
Scott Pitnick’s tattoo isn't exactly subtle. The massive black-and-white sperm twists and spires up his right forearm, appearing to burrow in and out of his skin before emerging into a fist-sized head on his bicep. Nor is the Syracuse University biologist reserved about his unusual body art, which once made an appearance in a montage of notable scientist tattoos published in The Guardian. For Pitnick, his intricate ink reflects his deep fascination in sperm’s “unbelievably unique biology.” Consider, he says, that sperm are the only cells in the body destined to be cast forth into a foreign environment—a feat that requires dramatic physical changes as they travel from the testes into a woman’s reproductive tract.
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“No other cells do that,” says Pitnick, who has been studying sperm for more than 20 years. “They have this autonomy.”
In his lab, Pitnick engineers the heads of fruit fly sperm to glow a ghostly red and green so that he can observe them moving through dissected female fly reproductive tracts. He hopes his work will help reveal how sperm behave within female bodies, an area of research that's still in its relative infancy. These kinds of innovations could one day explain the great diversity of sperm shape and size across the animal kingdom. Moreover, they could ultimately help researchers develop human infertility treatments, as well as more effective male contraceptives.
“We understand almost nothing about sperm function, what sperm do,” Pitnick says. Many of the answers to these unknowns likely hide within the other half of sperm’s puzzle: female bodies.
This might come as a disappointment to the courageous biologists who first looked upon sperm cells in their full glory in the 17th and 18th century, using the then-revolutionary microscope. These early sperm scientists found themselves tasked with answering the most basic of questions, for instance: Are sperm living animals? Are they parasites? And, Does each sperm contain a tiny pre-formed adult human curled up inside? (We’ll get to that one later.)
image: https://public-media.smithsonianmag.com/filer/7d/b8/7db8111d-000d-4ef4-b057-6c60dceeeafb/sperm_image_1-wr.jpg
Leeuwenhoek's early microscopic observations of rabbit sperm (figs. 1-4) and dog sperm (figs. 5-8). (Wikimedia Commons)The person with the dubious honor of being the first to study sperm in detail was Anton van Leeuwenhoek, a Dutchman who developed the early compound microscope. Van Leeuwenhoek first used his new tool to examine more chaste subjects such as bee stingers, human lice and lake water in the mid-1670s.
Colleagues urged him to turn his lens to semen. But he worried it would be indecent to write about semen and intercourse, and so he stalled. Finally, in 1677, he gave in. Examining his own ejaculate, he was immediately struck by the tiny “animalcules” he found wriggling inside.
Hesitant to even share his findings with colleagues—let alone get a wriggler tattooed on his arm—van Leeuwenhoek hesitantly wrote to the Royal Society of London about his discovery in 1677. “If your Lordship should consider that these observations may disgust or scandalise the learned, I earnestly beg your Lordship to regard them as private and to publish or destroy them as your Lordship sees fit.”
His Lordship (aka the president of the Royal Society) did opt to publish van Leeuwenhoek’s findings in the journal Philosophical Transactions in 1678—thus begetting the brand new field of sperm biology.
Even after van Leeuwenhoek discovered sperm in 1677, roughly 200 years passed before scientists agreed on how humans formed. Two primary fields of thought emerged along the way: On the one hand, the “preformationists” believed that each spermatozoa—or each egg, depending on who you asked—contained a tiny, completely pre-formed human. Under this theory, the egg—or sperm—simply provided a place for development to occur.
On the other hand, “epigenesists” argued that both males and females contributed material to form a new organism, though they weren’t sure who contributed exactly what. Discoveries throughout the 1700s offered more evidence for this argument, including the 1759 discovery that chicks develop organs incrementally.
Dog & rabbit sperm cell
2 ladies (his wife and daughter)
Hooke isn't as well known as some of his contemporaries. But he did make a place for himself in the history books when he looked at a sliver of cork through a microscope and noticed some "pores" or "cells" in it. Hooke believed the cells had served as containers for the "noble juices" or "fibrous threads" of the once-living cork tree. He thought these cells existed only in plants, since he and his scientific contemporaries had observed the structures only in plant material.
Hooke recorded his observations in the Micrographia, the first book describing observations made through a microscope. The drawing to the top left, of a flea observed through his microscope, was created by Hooke. Hooke was the first person to use the word "cell" to identify microscopic structures when he was describing cork.
flea
Tyudor swan
Metayas shlayden
Schleiden was educated at Heidelberg (1824–27) and practiced law in Hamburg but soon developed his hobby of botany into a full-time pursuit. Repelled by contemporary botanists’ emphasis on classification, Schleiden preferred to study plant structure under the microscope. While professor of botany at the University of Jena, he wrote “Contributions to Phytogenesis” (1838), in which he stated that the different parts of the plant organism are composed of cells or derivatives of cells. Thus, Schleiden became the first to formulate what was then an informal belief as a principle of biologyequal in importance to the atomic theory of chemistry. He also recognized the importance of the cell nucleus, discovered in 1831 by the Scottish botanist Robert Brown, and sensed its connection with cell division. Schleiden was one of the first German biologists to accept Charles Darwin’s theory of evolution. He became professor of botany at Dorpat, Russia, in 1863.
In 1838, Theodor Schwann and Matthias Schleiden were enjoying after-dinner coffee and talking about their studies on cells. It has been suggested that when Schwann heard Schleiden describe plant cells with nuclei, he was struck by the similarity of these plant cells to cells he had observed in animal tissues. The two scientists went immediately to Schwann’s lab to look at his slides. Schwann published his book on animal and plant cells (Schwann 1839) the next year, a treatise devoid of acknowledgments of anyone else’s contribution, including that of Schleiden (1838). He summarized his observations into three conclusions about cells:
The cell is the unit of structure, physiology, and organization in living things.
The cell retains a dual existence as a distinct entity and a building block in the construction of organisms.
Cells form by free-cell formation, similar to the formation of crystals (spontaneous generation).
We know today that the first two tenets are correct, but the third is clearly wrong. The correct interpretation of cell formation by division was finally promoted by others and formally enunciated in Rudolph Virchow’s powerful dictum, Omnis cellula e cellula,: “All cells only arise from pre-existing cells”.
In 1838, Theodor Schwann and Matthias Schleiden were enjoying after-dinner coffee and talking about their studies on cells. It has been suggested that when Schwann heard Schleiden describe plant cells with nuclei, he was struck by the similarity of these plant cells to cells he had observed in animal tissues. The two scientists went immediately to Schwann’s lab to look at his slides. Schwann published his book on animal and plant cells (Schwann 1839) the next year, a treatise devoid of acknowledgments of anyone else’s contribution, including that of Schleiden (1838). He summarized his observations into three conclusions about cells:
The cell is the unit of structure, physiology, and organization in living things.
The cell retains a dual existence as a distinct entity and a building block in the construction of organisms.
Cells form by free-cell formation, similar to the formation of crystals (spontaneous generation).
We know today that the first two tenets are correct, but the third is clearly wrong. The correct interpretation of cell formation by division was finally promoted by others and formally enunciated in Rudolph Virchow’s powerful dictum, Omnis cellula e cellula,: “All cells only arise from pre-existing cells”.
Rudolf virkow
The LMNA gene produces the lamin A protein which is the structural scaffolding that holds the nucleus of a cell together. The abnormal lamin A protein that causes Progeria is called progerin. Progerin makes the nucleus unstable. That cellular instability leads to the process of premature aging and disease in Progeria.
Example :Leon Botha
Where cell division occur.
Huntington's disease (HD) is a hereditary and progressive brain disorder. You can't "catch" it from another person. Although symptoms may first show up in midlife, Huntington's can strike anyone from childhood to advanced age. Over 10 to 25 years, the disease gradually kills nerve cells in the brain
The mutation, an expanded CAG repeat, is translated into an extended polyglutamine tract in the huntingtin protein (HTT), which leads to protein misfolding, accumulation of sticky protein aggregates in both cytoplasm and nucleus, and degeneration of neurons, first in the brain's striatum and later in the cortex and elsewhere.
Pseudohypoparathyroidism:
It is an inherited disorder which signifies defective signalling across the plasma membranes of several types of target cells. In that affected cell, the parathormone signal is normally mediated by activation of adenylate cyclase. There is a defective coupling protein in the membrane that prevents transmission of the extracellular hormone signal to the adenylate cyclase.
PTH helps control calcium, phosphorus, and vitamin D levels in the blood and bone. If you have PHP, your body produces the right amount of PTH, but is "resistant" to its effect. This causes low blood calcium levels and high blood phosphate levels. PHP is caused by abnormal genes.
Mitochondrial DNA-associated Leigh syndrome is a progressive brain disorder that usually appears in infancy or early childhood.[1] Affected children may experience vomiting, seizures, delayed development, muscle weakness, and problems with movement. Heart disease, kidney problems, and difficulty breathing can also occur in people with this disorder. Mitochondrial DNA-associated Leigh syndrome is a subtype of Leigh syndrome and is caused by changes in mitochondrial DNA. Mutations in at least 11 mitochondrial genes have been found to cause mtDNA-associated Leigh syndrome.[2] This condition has an inheritance pattern known as maternal or mitochondrial inheritance.[2][3] Because mitochondria can be passed from one generation to the next only through egg cells (not through sperm cells), only females pass mitochondrial DNA-associated Leigh syndrome to their children.
It makes lysosomes.
Achondrogenesis is a number of disorders that are the most severe form of congenital chondrodysplasia (malformation of bones and cartilage). These conditions are characterized by a small body, short limbs, and other skeletal abnormalities. As a result of their serious health problems, infants with achondrogenesis are usually born prematurely, are stillborn, or die shortly after birth from respiratory failure. Some infants, however, have lived for a while with intensive medical support.
Achondrogenesis type 1A is caused by a defect in the microtubules of the Golgi apparatus. In mice, a nonsense mutation in the thyroid hormone receptor interactor 11 gene (Trip11), which encodes the Golgi microtubule-associated protein 210 (GMAP-210), resulted in defects similar to the human disease.
3 kinds of protein filaments-the actin filament, intermediate filament and microtubules
-examples: trypanosoma bruceii; amoeba, dinoflagelettes, diatoms
-pro-before; karyote-nucleus
-Prokaryotic cell lacks a nuclear membrane. Its nuclear materials occupy a space in the cell called the central body 0r nucleoloid. The prokaryotic nucleus is described as incipient and the organisms with this type of nucleus are referred to as prokaryote. Eukaryotic nuclear materials are enclosed by a nuclear membrane.
Primary growth-increasing height and length
Example vascular and cork cambium
3. Intercalary occurs in the opposite direction of internode that part of stem wherein the internode is the area for elongation.
In dicot stems, a vascular cambium is present between the xylem and phloem. By the repeated division of the cell, this lateral mersitem produces secondary phloem and xylem.
In an old dicot stem, the central pith is completely replaced by the xylem. The entire xylem tissue inside the vascular cambium is referred to as ‘wood’ and all tissues outside the vascular cambium from the bark.
Parenchyma-photosynthetic tissue of leaf, soft flesh of fruit, storage tissue of roots and seeds
Collenchyma – form strands along the veins in leaves (providing support and strenght against the onslaught of strong winds and rain)
Sclerenchyma – strengthening elements to support mature plants.