CYTOGENETICS: L2 (P)

CYTOGEN SISIRA NG ISANG LINGGO KO

Cytology

The study of cells

Robert Hooke (1665)

Made use of an improvised microscope to examine a cork (plant). Called what he saw as “cells”

Antonie van Leeuwenhoek (1673)

a Dutch microscope maker, was first to view organisms (living things), he used a simple, handheld microscope to view pond water and scrapings from his teeth

Robert Brown (1833)

Discovered the nucleus

Matthias Schleiden (1838)

A German botanist that discovered the cells in plants. All plants "are composed of cells"

Theodor Schwann (1838)

Discovered that animals were made of cells

Rudolf Virchow (1855)

a German medical doctor that observed that cells divide, he reasoned that all cells come from other preexisting cells by cell division. Debunked Theory of Spontaneous Generation

All things are made of cells

Cell Theory states that:

• _______________

• Cells are the basic units of structure and function in an organism (basic unit of life)

• Cells come from the reproduction of existing cells (cell division)

Cells are the basic units of structure and function in an organism (basic unit of life)

Cell Theory states that:

• All things are made of cells

• _______________

• Cells come from the reproduction of existing cells (cell division)

Cells come from the reproduction of existing cells (cell division)

Cell Theory states that:

• All things are made of cells

• Cells are the basic units of structure and function in an organism (basic unit of life)

• _______________

PLASMA MEMBRANE

• External lipid membrane aka Plasmalemma

• Function: Dynamic interface with the external environment - For transfer of nutrient and metabolites

• Attachment of the cell to adjacent cells and extracellular matrix

• Communication with the external environment

Polar

• PLASMA MEMBRANE STRUCTURE:

  • 1. _____ - hydrophilic(water loving), head, glycerol conjugated to a nitrogenous compound

  • 2. Non-Polar - hydrophobic (water hating), tail, two-long chain fatty acids

Non-Polar

• PLASMA MEMBRANE STRUCTURE:

  • 1. Polar - hydrophilic(water loving), head, glycerol conjugated to a nitrogenous compound

  • 2. _____ - hydrophobic (water hating), tail, two-long chain fatty acids

Nucleus

• Largest organelle in the cell

• Control center of the cell, containing the "blueprint"

Nuclei

• Heterogenous structures with electron- dense and electron- lucent (light) areas

• Heterochromatin- dense areas (tightly-coiled inactive chromatin)

• Euchromatin- electron-lucent nuclear material that is active in RNA synthesis

• Heterochromatin and Euchromatin are called Chromatin

Nucleolus

• Sites of ribosomal RNA synthesis and ribosome assembly

• Ribosomal RNA and proteins, synthesized in the cytoplasm and imported back into the nucleus, are assembled into subunits

• The subunits then passed back to the cytoplasm to aggregate the complete ribosomes.

Microfilament

• Narrowest (diameter is about 7 nm)

• made up of many linked monomers of a protein called actin (also known as actin filaments)

• combined in a structure that resembles a double helix.

• come together to form linear, rod-like bundles, but they can also form branching networks with the assistance of proteins that anchor new side branches.

• Actin is a key part of the cytoskeleton and is found in virtually all types of eukaryotic cells.

• Key Role: Serves as tracks for the movement of a motor protein called myosin, which can also form filaments

Intermediate Filaments

• A type of cytoskeletal element made of multiple strands of fibrous proteins wound together.

• Average diameter of 8 to 10 nm

• Unlike microfilaments, which are always made of actin, intermediate filaments come in a number of different varieties, each one made up of a different type of protein monomer

• One familiar protein that forms intermediate filaments is keratin, a fibrous protein found in hair, nails, and skin found in many types of animal cells, but typically not in plants or fungi.

Microtubules

• Actually the largest of the three types of cytoskeletal fibers (diameter is about 25 nm)

• Made up of tubulin proteins arranged to form a hollow, straw like tube, and each tubulin protein consists of two subunits, a-tubulin and B-tubulin.

• Microtubules, like actin filaments, are dynamic structures, and they can grow and shrink quickly by the addition or removal of tubulin dimers. Microtubules have directionality, meaning that they have two ends that are structurally different from one another.

Centrosome, Centriole

• A structure found near the nucleus of animal cells, serves as a microtubule-organizing center.

• It contains a pair of hollow, rod-like structures that lie perpendicular to each other.

• Each centriole is a cylinder of nine triplets of microtubules, with nontubulin proteins to hold the triplets together.

• Anchor and initiate microtubules, and these proteins give the centrosome its microtubule-organizing capabilities. It surrounds centrioles

• Plant and fungal cells don't have centrosomes with centrioles, but they do have microtubule-organizing centers that play similar roles.

Flagella, Cilia

• Flagella (singular, flagellum) are long, hair-like structures that extend outward from the plasma membrane and are used to move an entire cell

• Cilia (singular, cilium) resemble flagelta, but are shorter and can generally be divided into two different categories: motile cilia and primary cilia.

• Like flagella, motile cilia generate power by beating, but unlike flagella, they are usually found in large numbers on the cell surface

Golgi Apparatus

• A series of flattened sacs that modifies, package stores, and transports materials out of the cell.

• Works with the ribosomes and ER

• Has a shipping side and receiving side

• Consist of several flattened tubular membranes stacked upon each other termed CISTERNAE and dilated terminal areas as either end of the cisternae called VACUOLES.

Lysosomes

• Recycling center, recycles cellular debris

• Helps digest food particles inside or outside the cell

• Contains digestive enzymes. Breaks down food, bacteria, and worn-out cell parts for cells

• Programmed for cell death (apoptosis)

Rough Endoplasmic Reticulum

• Found near the nucleus and typically forms large, flat sheets. As the ribosomes attached to the rough ER synthesize proteins, they feed the newly forming polypeptide chains into the lumen inside the rough ER.

• Another important role of the rough ER is to synthesize new phospholipids for cell membranes.

Mitochondria

• Scattered free in cytoplasm

• Relatively large, elongated organelles which have a smooth outer membrane and a convoluted inner membrane system.

• “Powerhouse of the cell".

• Chloroplast - found in the plants, algae and certain protozoans

• Associated with photosynthesis- major energy trapping on earth

Mitochondria

• The process of making ATP using the chemical energy found in glucose and other nutrients is called cellular respiration, and its oxygen-requiring steps take place inside the mitochondria.

• Mitochondria are oval-shaped organelles with two membranes: an outer one, surrounding the entire organelle, and an inner one, with many invaginations (inward protrusions) called cristae that maximize surface area

Osteocytes

Types of cells:

• There are about 260 variations

• Based on tissues they can form:

  • __________

  • Chondrocytes

  • Nerve cells

  • Epithelial cells

  • Muscle cells

  • Secretory cells

  • Adipose cells

  • Blood cells

• Based on function”

  • Conductive cells

  • Connective cells

  • Glandular cells

  • Storage cells

• Somatic vs Gametic Cells

Chondrocytes

Types of cells:

• There are about 260 variations

• Based on tissues they can form:

  • Osteocytes

  • __________

  • Nerve cells

  • Epithelial cells

  • Muscle cells

  • Secretory cells

  • Adipose cells

  • Blood cells

• Based on function”

  • Conductive cells

  • Connective cells

  • Glandular cells

  • Storage cells

• Somatic vs Gametic Cells

Nerve cells

Types of cells:

• There are about 260 variations

• Based on tissues they can form:

  • Osteocytes

  • Chondrocytes

  • __________

  • Epithelial cells

  • Muscle cells

  • Secretory cells

  • Adipose cells

  • Blood cells

• Based on function”

  • Conductive cells

  • Connective cells

  • Glandular cells

  • Storage cells

• Somatic vs Gametic Cells

Epithelial cells

Types of cells:

• There are about 260 variations

• Based on tissues they can form:

  • Osteocytes

  • Chondrocytes

  • Nerve cells

  • __________

  • Muscle cells

  • Secretory cells

  • Adipose cells

  • Blood cells

• Based on function”

  • Conductive cells

  • Connective cells

  • Glandular cells

  • Storage cells

• Somatic vs Gametic Cells

Muscle cells

Types of cells:

• There are about 260 variations

• Based on tissues they can form:

  • Osteocytes

  • Chondrocytes

  • Nerve cells

  • Epithelial cells

  • __________

  • Secretory cells

  • Adipose cells

  • Blood cells

• Based on function”

  • Conductive cells

  • Connective cells

  • Glandular cells

  • Storage cells

• Somatic vs Gametic Cells

Secretory cells

Types of cells:

• There are about 260 variations

• Based on tissues they can form:

  • Osteocytes

  • Chondrocytes

  • Nerve cells

  • Epithelial cells

  • Muscle cells

  • __________

  • Adipose cells

  • Blood cells

• Based on function”

  • Conductive cells

  • Connective cells

  • Glandular cells

  • Storage cells

• Somatic vs Gametic Cells

Adipose cells

Types of cells:

• There are about 260 variations

• Based on tissues they can form:

  • Osteocytes

  • Chondrocytes

  • Nerve cells

  • Epithelial cells

  • Muscle cells

  • Secretory cells

  • __________

  • Blood cells

• Based on function”

  • Conductive cells

  • Connective cells

  • Glandular cells

  • Storage cells

• Somatic vs Gametic Cells

Blood cells

Types of cells:

• There are about 260 variations

• Based on tissues they can form:

  • Osteocytes

  • Chondrocytes

  • Nerve cells

  • Epithelial cells

  • Muscle cells

  • Secretory cells

  • Adipose cells

  • __________

• Based on function”

  • Conductive cells

  • Connective cells

  • Glandular cells

  • Storage cells

• Somatic vs Gametic Cells

Conductive cells

Types of cells:

• There are about 260 variations

• Based on tissues they can form:

  • Osteocytes

  • Chondrocytes

  • Nerve cells

  • Epithelial cells

  • Muscle cells

  • Secretory cells

  • Adipose cells

  • Blood cells

• Based on function”

  • __________

  • Connective cells

  • Glandular cells

  • Storage cells

• Somatic vs Gametic Cells

Connective cells

Types of cells:

• There are about 260 variations

• Based on tissues they can form:

  • Osteocytes

  • Chondrocytes

  • Nerve cells

  • Epithelial cells

  • Muscle cells

  • Secretory cells

  • Adipose cells

  • Blood cells

• Based on function”

  • Conductive cells

  • __________

  • Glandular cells

  • Storage cells

• Somatic vs Gametic Cells

Glandular cells

Types of cells:

• There are about 260 variations

• Based on tissues they can form:

  • Osteocytes

  • Chondrocytes

  • Nerve cells

  • Epithelial cells

  • Muscle cells

  • Secretory cells

  • Adipose cells

  • Blood cells

• Based on function”

  • Conductive cells

  • Connective cells

  • __________

  • Storage cells

• Somatic vs Gametic Cells

Storage cells

Types of cells:

• There are about 260 variations

• Based on tissues they can form:

  • Osteocytes

  • Chondrocytes

  • Nerve cells

  • Epithelial cells

  • Muscle cells

  • Secretory cells

  • Adipose cells

  • Blood cells

• Based on function”

  • Conductive cells

  • Connective cells

  • Glandular cells

  • __________

• Somatic vs Gametic Cells

Somatic

Types of cells:

• There are about 260 variations

• Based on tissues they can form:

  • Osteocytes

  • Chondrocytes

  • Nerve cells

  • Epithelial cells

  • Muscle cells

  • Secretory cells

  • Adipose cells

  • Blood cells

• Based on function”

  • Conductive cells

  • Connective cells

  • Glandular cells

  • Storage cells

• _____ vs Gametic Cells

• Gametic

Types of cells:

• There are about 260 variations

• Based on tissues they can form:

  • Osteocytes

  • Chondrocytes

  • Nerve cells

  • Epithelial cells

  • Muscle cells

  • Secretory cells

  • Adipose cells

  • Blood cells

• Based on function”

  • Conductive cells

  • Connective cells

  • Glandular cells

  • Storage cells

• Somatic vs _____ Cells

Differentiation

The process by which cells assume specialized structure and function