Biology - Lesson 1 and 2, Cell

Cell

Basic unit of life

Cytology

The study of cells

Microscope

An optical device we use to see and observe things that cannot be seen through the naked eye

Phospholipids

Basis of the biological membrane

1. Red Blood Cells
2. Nerve Cells

Two examples of cells

Red Blood Cells (Erythrocytes)

- Oval biconcave disk shape
- Lacks a nucleus
- Most abundant in the body but is smaller compared to white blood cells
- Has a lifespan of 120 days
- Produced in the bone marrow
- Contains hemoglobin

Hemoglobin

is a special protein substance that carries oxygen to the blood

Nerve Cells

- Fundamental and functional unit of the entire system of the brain
- Star like in shape
- Carries information to the brain and vice versa.

Cell Body

The oval at the center of the body of the Nerve Cell

Dendrites

The short projections of the Nerve Cell

Axon

The long single branch of the Nerve Cell

1. Prokaryotic Cell
2. Eukaryotic Cell

What are the Two Types of Cells?

Prokaryotic Cell

- Unicellular
- Lacks a nucleus and other organelles

Eukaryotic Cell

- Multicellular
- Contains a nucleus and other organelles
- Plant Cells
- Animal Cells

1. Composition of the cell membrane
2. Metabolic activities they perform
3. Similarity of boundary parts (cell membrane) and complex material inside
4. Composition of chemical compounds (organic and inorganic)

What are the Common Characteristics of a Cell?

Robert Hooke

- English scientist
- Discovered cell in 1665
- Used his own made microscope
- Cork (oak cork)
- Coined the term Cellular

Cellular

means relating to or consisting of cells

Antoine Van Leeuwenhook

- Dutch Naturalist
- Joined Hooke in the studying the cell
- Father of Microscopy and Microbiology
- Discovered Animalcules

Animalcules

- are also known as microorganisms
- Discovered by Leeuwenhook from the drop of rain water

Robert Brown

- Scottish Botanist
- Described Nucleus in detail in 1831

Felix Dujardin

- French Biologist
- 1835
- Discovered Sarcode

Sarcode

- Now known as Protoplasm
- Semi transparent living substance

Matthias Schleiden

- German Botanist
- 1838
- Plant Cell

Theodore Schwan

- German Zoologist
- 1839
- Animal Cell

Rudolf Virchow

- German Physician
- 1858
- "Omnis cellula e cellula"

"All living cells come from other existing cells"

"Omnis cellula e cellula" means?

1. Cells are the building blocks and the functional unit of all living organisms
2. All living organisms contain one or more cells
3. Cells arise from pre-existing cells

What is the Classic Cell Theory?

1. All living organisms are composed of trillions of cells inside the body
2. Cell is the fundamental building block of the body
3. Cell comes from other cells by cell division
4. The cells of an organism within a similar species are mostly the same, both structurally and chemically
5. The cell consists of genetic material which is passed from generation up to the last generation

What is the Modern Cell Theory?

1. Cell Membrane / Plasma Membrane / Plasmalemma
2. Cytoplasm
3. Nucleus

What are the 3 Major Parts of the Cell?

Cell Membrane

- Semi-permeable membrane
- Made up of phospholipid bilayer, fats, carbohydrates, and protein materials
- Supports and gives shape to the cell
- Acts as receptor sites

Cell Wall

- External boundary that is located in plants only
- Consists of a Cellulose structure
- Protects the plants from invading Pathogenic organisms
- Prevents dryness

Pathogens

are invasive microorganisms

Cellulose

- Located outside the nucleus, but inside the cell membrane
- Composed of Cytosol
- Contains organelles and inclusions
- Its main functions are cell expansion, growth, metabolic activities, and cell replication
- is a complex carbohydrate
- is located at the center of the cell

Cytosol

is a jelly-like, semi-transparent fluid
It gives structural support and holds the organelles inside the cell

Organelles (Cytoplasmic Organelles)

- Translates to "little organ"
- Is a membrane enclosed with a specialized subunit inside the cell
- Usually enclosed within its own lipid bilayers
- Are suspended in the cytoplasm
- Each has its own structural characteristics

Ribosomes

- Small rounded dark bodies
- Composed of ribosomal proteins and nucleic acids
- Connects amino acids together
- Builders of protein materials and are responsible for protein synthesis
- Also known as the protein factory

Amino acids

are the building blocks of protein

Endoplasmic Reticulum

- Network of interconnected tubes and flattened sacs
- Highway of the cell
- Extends in the cisternae

Cisternae

is the membranous tube-like structure

1. Rough Endoplasmic Reticulum
2. Smooth Endoplasmic Reticulum

What are the Two Parts of the Endoplasmic Reticulum?

Rough Endoplasmic Reticulum

- Contains ribosome studs
- Manufactures protein materials and protein folding
- Is the site of protein synthesis

Smooth Endoplasmic Reticulum

- Lacks ribosomes
- Responsible for manufacturing lipids and detoxifying
- Carries carbohydrates, lipids, and non-protein materials

Detoxifying

means to make toxins in less, inactive forms.

Golgi Apparatus/Golgi Bodies

- Also known as Dictyosome
- Made up of stacks of flattened membrane sacs
- Packages (vesicles) and secretes proteins
- Post Office/Packaging Center of the cell

Mitochondria

- Powerhouse of the cell
- Produces energy
- Is the site for synthesizing ATP
- Sausage shape like organelle
- Site for cellular respiration

Adenosine Triphosphate

Is the energy currency of cells

Cristae

Outer Membrane of the Mitochondria

Matrix

Inner membrane of the Mitochondria

Vacuoles

- For storage of materials and water, releasing of cellular waste products, and maintaining hydrostatic pressure
- Large in plants as it serves for storage of water
- Small in Animals as it serves for the storage of food products

Lysosomes

- "Scavenger of the cell" or the "suicidal bag of the cell"
- Contains strong hydrolytic enzymes and is used by the cell to digest macromolecules
- Digested products are reused again for synthetic of cellular materials

Glycocalyx (Cell Coat)

- Located in the outer part of the membrane of animal cells only
- Functions for cell recognition and cellular adhesion
- Responsible for tissue organization

Adhesion

means attachment

Peroxisomes

- Membranous sacs that contain oxidative enzymes for detoxifying harmful substances

Cytoskeleton

- Cell framework of the fundamental framework of the cytoplasm
- Contains protein filaments that assists for organelles to move inside
- Contains microtubules

Microtubules

- is a collective network of protein filamentous, thread-like structure
- are microfilaments which produce a strong ability to support and maintain cell shape

Plastids

- Largest, rounded membranous organelles that contain DNA
- Located in plant cells for coloring pigments in plants
- Double-membranous structure enclosed by a thylakoid membrane

Deoxyribonucleic Acid

Is a molecule that contains genetic information

1. Chloroplastids
2. Chromoplastids
3. Leucplastids

What are the 3 Types of Plastids?

Chloroplastids

Green pigments

Chromoplastids

Red, yellow, orange pigments

1. Carotenoids
2. Anthocyanin
3. Anthoxanthin
4. Xanthophyll

What are the 4 Types of Chromoplastids?

Carotenoids

Orange pigment

Anthocyanin

red, blue, or purple pigment

Anthoxanthin

white, creamy, or yellow pigment

Xanthophyll

yellow pigment

Leucoplastids

White and colorless pigments

Amyloplasts
Proteinoplasts
Elaioplasts

What are the 3 types of Leucoplastids?

Amyloplasts

- stored starch grains

Proteinoplasts

- stored protein

Elaioplasts

- stored oil substance

Centriole

- Small, fibrous structure and cylindrical in shape
- Replicate as the cell divides
- Absent in plants and fungi
- Most important in cell division

Centrosome

- Located inside this is a pair of Centrioles

Cell Division

- is a cycle in which the cell grows and replicates before dividing
- Mitosis and Meiosis

Nucleus

- Control center and brain of the cell
- Contains hereditary factors
- is the transmitter, controller of information, and carrier of genes.

1. Nuclear Envelope
2. Nucleoplasm
3. Nucleolus
4. Chromosomes
5. Flagella
6. Cilia

What are the Parts of the Nucleus?

Nuclear Envelope

- Consists of two membranous layers
- Surrounds the entire nucleus
- Serves as a boundary to separate nuclear material from the cytoplasm and nuclear membrane
- Controls the continuous flow of materials
- Semi permeable and porous

Nucleoplasm

- Contains fluid substance that is suspended in the internal part forming the Protoplasm of the nucleus

Protoplasm

is also known as Karyoplasm

Nucleolus

- Contains RNA
- Rich of protein materials for the protein synthesis and carrying hereditary traits

Ribosomal Nucleic Acid

Is the blueprint for protein synthesis

1. mRNA
2. tRNA
3. rRNA

What are the 3 Types of RNA?

mRNA

- messenger, makes copy of DNA

tRNA

- transfers and carries amino acids

rRNA

- ribosomal, pairing of codon and anticodon

Chromosomes

- Contains DNA embedded inside the chromosomes
- Also bounds protein which serves as a packaging for DNA
- Controls hereditary characteristics

Flagella

- Cytoplasmic projections
- Covered by plasma membrane
- Tail-like
- Used for propulsion
- Used for locomotion

Cilia

- Short projections
- Hair-like
- Used for ciliary action or wave-like movements
- Also used for locomotion

Cell Modification

- A process that occurs after cell division

Cell

Basic structural and functional unit of Life