El sistema inmunitario

El sistema inmunitario es complejo y comprende multitud de elementos. Para hacernos una idea general veamos el siguiente esquema.

En la siguiente imagen se muestran los órganos que forman parte del sistema inmunitario

Veamos los elementos del sistema inmunitario y su ámbito de actuación en el siguiente vídeo

Puedes reconocer muchos de sus elementos en este simpático vídeo de la famosa serie de TV La vida es así

Cell division: mitosis & meiosis

Cell cycle and mitosis in 3D                                  

Cell cycle quizz

The stage of the cell cycle where each chromosome is composed of two chromatids in preparation for mitosis.

A.	G1
B.	S
C.	M
D.	G2

Which sequence of the cell cycle is common to eukaryotes?

A.	G1 to G2 to S to M to cytokinesis
B.	G1 to M to G2 to S to cytokinesis
C.	G1 to S to M to G2 to cytokinesis
D.	G1 to S to G2 to M to cytokinesis

The stage of the cell cycle where the cell is preparing to begin DNA replication is called:

A.	G1
B.	G2
C.	S
D.	M

Prior to cell division, each chromosome replicates or duplicates its genetic material. The products are connected by a centromere and are called:

A.	sister chromosomes
B.	homologous chromosomes
C.	sex chromosomes
D.	sister chromatids

The first stage of mitosis when chromosomes start becoming visible in the microscope is called:

A.	anaphase
B.	prophase
C.	telophase
D.	metaphase

To check your answers or learn more, please go to this link

Meiosis                                                                   

Cell meiosis quizz

A human cell has 46 total or 23 pairs of chromosomes. Following mitosis, the daughter cells would each have a total of ______ chromosomes. After meiosis I, the two daughter cells would have _____chromosomes, and after meiosis II ______ chromosomes.

A.	46, 46, 46
B.	46, 23, 23
C.	23, 23, 23
D.	46, 12, 12

The process of meiosis produces four cells with nonidentical chromosomes. This diversification occurs during:

A.	telophase I
B.	prophase I
C.	metaphase II
D.	prophase II

One of the earliest events that distinguishes meiosis occurs in prophase I and involves:

A.	Condensation of chromosomes
B.	Loss of the nuclear membrane
C.	Movement of chromosomes towards the metaphase plate
D.	Pairing of homologous chromosomes

_________________ most closely resembles events of mitosis except that the cells are ___________.

A.	interphase, diploid
B.	meiosis II, diploid
C.	interphase, haploid
D.	meiosis II, haploid

If you get less than 50% of correct answers, please have this test 

Actividades sobre los orgánulos celulares de las células eucariotas

Mira la presentación que aparece en el enlace y trata de realizar las actividades que se proponen más abajo



En este enlace encontrarás actividades para conocer más sobre los orgánulos celulares.