3rdQtr_BiologyReviewer (1)

Robert Hooke

Observed cells in a thin slice of  cork (dead plant cells). Coined the term “Cells” due to the cells looking like small rooms that monks lived in called “cells”.

Anton Van Leeuwenhoek

• Credited for the discovery of single-celled microorganisms

• In 1674 discovered cells from living cells in pond water

• commonly regarded as "the Father of Microbiology"

Robert Brown

Discovered the Nucleus

Matthias Jacob Schleiden

• was a German botanist who, with Theodor Schwann, co founded the cell theory

• A botanist who concluded that all plants are made out of cells

Theodor Schwan

A zoologist who concluded that all animals are made out of cells.

Rudolf Virchow

In 1855, Rudolf Virchow published his now famous aphorism “omnis cellula e cellula”, “All cells are from other pre-existing cells” through Cell Division.

Unicellular

also known as a single-celled organism, is an organism that consists of a single cell

Escherichia coli, Diatoms, Protozoa, Protista

Unicellular Examples

Multicellular

organisms individual cells grow and then divide via a process called mitosis, thereby allowing the organism to grow

Humans, Trees, Chicken, Plants

Multicellular Examples

Mitosis

The process cells use to make exact replicas of themselves. Mitosis is observed in almost all the body’s cells, including eyes, skin, hair, and muscle cells.

Meiosis

In this type of cell division, sperm or egg cells are produced instead of identical daughter cells as in mitosis.

Binary Fission

Single-celled organisms like bacteria replicate themselves for reproduction.

Endosymbiotic theory

Unicellular Organisms engulf other Unicellular Organisms, causing these organisms to combine and live as one singular organism.

Eukaryotic Cells

• Has  nucleus with a nuclear envelope

• Bigger and more complex than prokaryotes

• Have membrane bound organelles such as (Golgi Apparatus, Endoplasmic Reticulum, Lysosomes, and etc.)

• Highly Organized DNA - Double-stranded helix and forms chromosomes

• Can be both unicellular or multicellular organisms

  • Examples are the ff:

    • Animals, plants, fungi.

Prokaryotic Cells

• No nucleus

• No membrane bound organelles (except for ribosomes)

• All prokaryotic cells are unicellular

• Prokaryotic cells are much more simpler and smaller than eukaryotic cells

• DNA - Single strand and circular

  • Examples are Bacteria

Animal Cells

Plant Cells

Bacteria Cells

Organelles

Is a microscopic structure in a cell that is surrounded by a membrane that has a specific function which is found in the cytoplasm. It may or may not be membrane-bound.

Cell Membrane or Plasma Membrane

• Composed of a double layer of phospholipids and proteins.

• It is the one which surrounds the outside of all cells.

• It has the capability to control what enters or leaves the cell.

• Cell membrane is fluid, therefore molecules found in the cell membranes are constantly moving and changing.

• It is considered as a living layer.

  • The cell membrane is a living membrane that consists of fine pores. It is a semi-permeable membrane which allows only certain substances to pass through

Phospholipids

• Heads contain glycerol and phosphate which are hydrophilic (attracts water)

• Tails are made of fatty acids and are hydrophobic (repels water)

• It makes up the bilayer found in the cell membrane.

• Can move laterally to allow small molecules such as oxygen, carbon dioxide, and water to enter.

Cell Membrane and Cell wall

• is against the cell wall in plant cells, it pushes out against the cell wall to maintain the cell's shape.

• Cell wall is outside of the cell membrane, it is a nonliving layer.

Cytoplasm

Jelly-like substance enclosed by cell membrane, which provides a medium for chemical reaction to take place.

Nucleus

• is usually the largest organelle found in the cell.

• controls the activities found in the cell.

• contains the DNA in chromosomes

  • DNA is spread out and appears as Chromatin in non-dividing cells.

  • DNA is condensed and wrapped around proteins forming Chromosomes in dividing cells.

• Bounded by a nuclear envelope with pores.

  • Double membrane surrounding the nucleus

  • Also called nuclear membrane

  • Contains nuclear pores for materials to enter and leave the nucleus.

Nucleolus

• Found inside the nucleus

• Disappears when the cell divides

• Makes ribosomes that make proteins.

Cytoskeleton

• Helps the cell in maintaining their cell shape.

• It allows the movement of organelles

• Made of proteins

• Microfilaments (threadlike) are made of Actin

• Microtubules (tubelike) are made of Tubulin

Centrioles

• Found only exclusively in animal cells

• Appear during cell division forming mitotic spindles

• Helps pull chromosome pairs apart to opposite ends of the cell.

Mitochondria

• “Powerhouse” of the cell

• Generates cellular energy (ATP)

• Site of Cellular Respiration (the burning of glucose)

• Mitochondria is surrounded by a double membrane has its own DNA, and has a folded inner membrane called Cristae which increases the mitochondria’s surface area for more chemical reaction

Endoplasmic Reticulum

• Network of hollow membrane tubules.

• Functions in synthesis of cell products and transport.

Rough Endoplasmic Reticulum

• Proteins are made by ribosomes on ER surface

• They are threaded into the rough ER to be modified and transported.

Smooth Endoplasmic Reticulum

• Creates membrane lipids (Steroids)

• Regulates Calcium (Muscle cells)

• Destroys Toxic Substances (Liver)

Ribosomes

• Made of Proteins and rRna

• “Protein Factories”

• Helps and joins in the process of protein synthesis alongside amino acids.

Golgi Bodies

• Modify, sort, and Package

• Helps process and package proteins and lipid molecules, especially proteins destined to be exported from the cell.

Lysosomes

• Contains digestive enzymes which break down food, bacteria, and worn out cell parts.

• Programmed for cell death (Apoptosis)

• Lyse and release enzymes to breakdown and recycle cell parts

Cilia and Flagella

• are shorter and is more frequently seen on the cells

• are longer and fewer seen on the cell, usually 1-3 on cells.

Vacuoles

• Fluid filled sacs for storage

• Small or absent in animal cells

• Plant cells have a large central vacuole

• In plants, they are capable of storing cell saps which Includes the storage of sugars, proteins, minerals, lipids, wastes, salts, water, and enzymes

Chloroplasts

• Uses energy from sunlight to create its own food (glucose)

• Energy from the sun is stored in chemical bonds made out of sugars.

• It’s surrounded by a double membrane, its outer membrane is smooth, while its inner membrane is modified into sacs called Thylakoids.

• Thylakoids in stacks are called Grana and are interconnected.

• Stroma is a gel-like material which surrounds thylakoids.

Cell transport

• is movement of materials across cell membranes.

Cell respiration

• is a chemical process in which oxygen is used to make energy from carbohydrates (sugars).

Photosynthesis

• is the process by which plants use sunlight, water, and carbon dioxide to create oxygen and energy in the form of sugar.

Cell division

• is the process by which a parent cell divides into two daughter cells. Cell division usually occurs as part of a larger cell cycle in which the cell grows and replicates its chromosomes before dividing.

Compartmentalization

In eukaryotes, specific cellular functions are compartmentalized into the cell nucleus and organelles surrounded by intracellular membranes. This compartmentalization vastly improves the efficiency of many cellular functions and prevents potentially dangerous molecules from roaming freely within the cell.

Apical

• Top surface of the cell

  • Cellular modifications found on the apical surface of the cell.

  • Absorption, locomotion/movement, and secretion

Cilia

are usually short, hair-like structures that move in waves.

Flagella

are long whip-like structures.

Apical

Cilia and Flagella

Villi

• are finger-like projections that arise from the epithelial layer In some organs. They help to increase surface area allowing for faster and more efficient adsorption

Microvilli

are smaller projections that arise from the cell surface which also increases surface area.

Apical

Villi and Microvilli

Pseudopods

• Temporary, irregular lobes formed by amoebas and some other eukaryotic cells.

• Bulge outward to move the cell or engulf prey.

Apical

Pseudopods

Extracellular Matrix

• Compound secreted by the cell on its apical surface.

• Cell wall is the extracellular structure in some cell types. Glycoprotein is the main ingredient of ECM in the animal cells.

Apical

Extracellular Matrix

Basal

• Bottom of the cell

  • Cellular modifications found on the basal surface of the cell.

  • Facilitate stable adhesion of cells

Desmosomes/Hemidesmosomes

• Anchoring junctions on the basal surface of the cell.

• Rivet-like links between cytoskeleton and the extracellular matrix components.

Basal

Desmosomes/ Hemidesmosomes

Lateral

• In between the cell

  • Cellular modifications found between cells. Or on the lateral surface of the cell.

Tight Junctions

• Acts as a barrier that regulates the movement of water and solutes between epithelial layers.

• Prevent leakage of ECF.

Lateral

Tight Junctions

Adhering Junctions

• Anchoring junction on the lateral surface of the cell

• Fasten cells together and provide a strong mechanical attachment to adjust cells.

Lateral

Adhering Junctions

Gap Junctions

• Communicating junctions

• Closable channels that connect the cytoplasm of adjoining cells

• Connections that allow direct exchange of chemicals between cytoplasm of two cells.

Lateral

Gap Junctions

Spherical Morphology

Ovum are female reproductive cells used in creating new organisms.

Sometimes red blood cells become mistaken as damaged cells, therefore destroyed.

Oval Morphology

Red blood cells elongate when passing through a capillary bed so that they won’t get stuck.

Ciliated Columnar Morphology

Are used to transport materials

The lungs can use goblet cells to transport unwanted particles.

i.e Goblet cells (trachea, bronchioles, and fallopian tubes.)

Stellate Morphology

Inhibitory Interneurons, it connects to different brain regions to exchange information between motor and sensory nerves.

i.e nuerons

Columnar Morphology

These cells are elongated and column-shaped and have a height of at least four times their width

Another function is to protect the digestive tract from any bacteria that may be ingested.

i.e goblet cells

Polygonal Morphology

Shaped like polygons, they are capable of maximizing space and storing for the body

i.e fat cells

Amorphous Morphology

No definite shape and have the capability to restructure their shape depending on their function in consuming pathogens in the body

i.e White Blood Cell and Pseudopods.

Fusiform Morphology

They collect and process inputs from auditory and other sources before transmitting information to higher levels of auditory system

i.e Biceps Brachii and muscle cells.

Active Transport

goes AGAINST the concentration gradient and uses ATP (energy), the concentration gradient goes from low to high concentration.

Passive transport

does not use energy and does not use ATP, the concentration gradient goes from high to low concentration.

Diffusion

• Food coloring, Diffusion is the net movement of anything generally from a region of higher concentration to a region of lower concentration. It does not require energy, it's considered as passive transportation.

Facilitated Diffusion

• Traveling into a greater to lesser concentration, because of this cellular energy. Facilitated diffusion is necessary to move molecules from one side of the membrane to the other without using energy.

Osmosis

is the movement of water molecules from a solution with a high concentration of water molecules to a solution with a lower concentration of water molecules, through a cell's partially permeable membrane. Passive Transport.

Isotonic solution

is one that has the same concentration of solutes both inside and outside the cell

Hypertonic solution

is one that has a higher solute concentration outside the cell than inside

Hypotonic solution

is one that has a higher solute concentration inside the cell than outside

Endocytosis (Phagocytosis)

is a general term describing a process by which cells absorb external material by engulfing it with the cell membrane.

Exocytosis (Pinocytosis)

is the fusion of secretory vesicles with the plasma membrane and results in the discharge of vesicle content into the extracellular space and the incorporation of new proteins and lipids into the plasma membrane.