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CELLSCELLS
Organelle
Cell
Tissue
Organ
Organ
System
Organism
Nucleus
Musclecell
Muscle
Heart
Circulatorysystem
Human
smaller?
bigger??
More examples??
“
“
“
“
Levels of organisation
of the life
Cell is the smallest unit of life,the smallest structure that is classified as aliving thing,
and is often called the building block of life- but I dont think this description is clear enough-
The cell is the basic structural and functional unit of an organism What does it mean?
All living things are made up of one or more cells.
All living cells come from pre-existing cells by division.
The activity of an organism depends on the total activity of individual cells.
All cells are basically the same in chemical composition in organisms of similar species.
1673 - Anton van Leuwenhoek used a handmade microscope to observe pond water & discoveredsingle-celled organisms
He called them “animalcules”
He also observed blood cells from fish, birds, frogs, dogs, and humans
Therefore, it was known that cells are found in animals as well as plants
Anton van Leuwenhoek
Microbios que Leeuwenhoek
observó (con un aumento que
superaba el de los primeros
microscopios con lentes múltiples).
MICROSCOPIO DE
LEEUWENHOEK Tornillos
para enfoque
Muestra en
la puntadel
alfiler
Lente
1665 – English scientist, Robert Hooke, discovered cells when he was looking through one of the first microscopes
Looked at a thin slice of cork and described what he saw as “tiny boxes or honeycombs”
Named the boxes “cells” as they reminded him of the cells in monasteries
Thought cells only existed in plants
Discovery of Cells – Robert Hooke
1833 – Robert Brown
Observed the nucleus in the epidermis of an orchid
Development of Cell Theory – 1800’s
1838 - Matthias Schleiden, a German professor of botany, identified the first plant cells and concluded that all parts of a plant is made of cells
1839 – Theodor Schwann, a German zoologist and a close friend of Schleiden, stated that all animal tissues are composed of cells.
Schleiden and Schwann
1855 – Rudolf Virchow, German doctor
Proved that cells come from other cells, not from non-living matter
“Omnis cellula e cellula”
Rudolf Virchow
Putting it all together:
The 3 Basic Components of the Cell Theory were now complete:
1. All living things are composed of one or more cells. (Schleiden & Schwann, 1838-39)
2. The cell is the basic unit of structure and function in all living things (Schleiden & Schwann, 1838-39)
3. All cells come from preexisting cells (Virchow, 1858)
The Complete Cell Theory
¿Por qué las células suelen ser pequeñas?
El cubo de 4 cm de arista, los ocho cubos de 2 cm de arista y los 64 cubos de 1 cm de arista tienen todos el mismo volumen. Pero al dividir el volumen en porciones, la superficie total aumenta.
Al ser las células pequeñas tienen mayor superficie (aumentando la eficacia de entrada y salida de materiales).
Cells have lots of different functions but
they are often specialised to do a
particular job.
For this reason each type of cell has
special characteristics that make it well
adapted at carrying out its functions.
We are going to study in detail just a few of the organelles in animal cells:
* mitochondria
* nucleus and DNA
* ribosomes
* ER + Golgi apparatus
mitochondria role: cellular respiration
°#Lèô‚#†_LÙ#¨éxŸÚ³.7G®#*jÝW±#5
GLÚCIDOS:estructura
C6H12O6
GLÚCIDOS:estructura
3.- POLISACÁRIDOS
glucosa, fructosa y galactosa No requieren digestión pues son pequeñas moléculas. De fórmula C6H12O6
Se disuelven en agua y tienen sabor dulce
Las simbolizaremos como
1.- MONOSACÁRIDOS
sacarosa y lactosa, uniones de dos monosacáridosRequieren digestión hasta monosacáridos para poder entrar en las células.Se disuelven en agua y tienen sabor dulce.
Las simbolizaremos como
2.- DISACÁRIDOS
+ +EnergíaEnergía
La ecuación anterior solo tiene sentido...
considerando el resultado aprovechable por los seres vivos cuando realizan el proceso:
LA ENERGÍA
Respiración celular
Nucleus role: containing DNA DNA carries the information for making
all of the cell's proteins.
Ribosome role: producing proteins. These proteins perform all of the functions
of a living organism
Deoxyribonucleic acid (DNA) is the master molecule of every cell. It control the making of other molecules (proteins)Although it may look complicated, the DNA in a cell is just a sequence made up of four different parts called nucleotides. Imagine a set of blocks that has only four shapes, or an alphabet that has only four letters. DNA is a long string of these blocks or letters.
DNA carries the information for making all of the cell's proteins.
These proteins carry out all of the functions of a living organism
When the cell reproduces, it has to pass all of this information -copy of DNA- to the daughter cells.
In DNA, each protein is encoded by a gene (a specific sequence of DNA) that determines the order of amino acids that must be put together to make a protein.
A protein is made of a long chain of chemicals called amino acids
20 types of amino acids in organisms
Depending on the sequence of amino acids, trillions different proteins
protein
Proteins have many functions:
EnzymesEnzymes that speed up chemical reactions (such as digestive enzymes)
Structural proteins that are building materials (such as collagen and nail keratin)
TransportingTransporting proteins that carry substances (such as oxygen-carrying haemoglobin in blood)
Contraction proteins that cause muscles to compress (such as actin and myosin)
Hormones - chemical messengers between cells (including insulin, growth hormone etcetera)
ProtectiveProtective proteins - antibodies of the immune system, clotting -coagulantes- proteins in blood
The particular sequence of amino acids in the protein chain is what makes one protein different from another. This sequence is encoded in the DNA where one gene encodes -CODIFICA- for one protein.
The particular sequence of amino acids in the chain is what makes one protein different from another. This sequence is encoded in the DNA where one gene encodes for one protein.
Ribosome making a new protein.A ribosome is made up of two round parts,the smaller subunit and the bigger subunit
Growing protein: two amin oacids so far -hasta ahora: M-R
The third amino acid is about to join the two previous amino acids
(1)
(2) (3)
Instructions in DNA
Instructions in DNA
Endoplasmic reticullum and
Golgi apparatus roles:
packaging proteins inside lysosomes OR
to be secreted outside the cell
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