1. CELLS STRUCTURE / FUNCTION / DIVERSITY DNA
CELL DIVISION (MITOSIS / MEIOSIS)
CELLULAR SPECIALIZATION

2. THE HUMAN CELL

3. THE CELL STRUCTURE & FUNCTION OF A HUMAN CELL
STRUCTURE & FUNCTION OF DNA
GENETIC DIVERSITY

4. THE HUMAN CELL - STRUCTURE
THE CELL IS THE BASIC UNIT OF LIFE
ALL LIVING THINGS MUST BE ABLE TO NOURISH THEMSELVES, BREATHE, ELIMINATE WASTE, GROW, AND REPRODUCE
STRUCTURE
1- CELL MEMBRANE – a flexible barrier that surrounds the cell content, allowing the cell to interact with its environment
2- CYTOPLASM – a gelatinous fluid inside the cell membrane and outside the nucleus
3- NUCLEUS – the cell’s control center (BRAIN OF CELL)

5. THE HUMAN CELL - FUNCTION
CELL MEMBRANE –
a) forms a barrier and protects the cell
b) facilitates the absorption of nutrients
c) facilitates the evacuation of waste

6. THE HUMAN CELL - FUNCTION
CYTOPLASM –
a) establishes an environment that is hospitable for most cell activities
b) includes the following parts:
MITOCHONDRIA: produce energy through cellular respiration
GOLGI APPARATUS: stores material produced by the cell and transports it to the cell membrane and outside the cell
ENDOPLASMIC RETICULUM: produces some of the material necessary for cell activities. Transports material from one cell to another.
RIBOSOMES: produces some of the material necessary for cell activities

7. THE HUMAN CELL - FUNCTION
CYTOPLASM (cont) –
CYTOSOL: contains cytoplasm
organelles and many dissolved substances
LYSOSOMES: digest certain
nutrients. Decompose and
recycle various cell
constituents

8. THE HUMAN CELL - FUNCTION
NUCLEUS –
a) contains and protects individual genetic information
b) controls all cell activities
NUCLEAR MEMBRANE: forms a barrier and protects the nucleus. Enables certain exchanges with the rest of the cell.
DNA: controls all cell activity. Controls all genetic information.

9. DNA – STRUCTURE & FUNCTION
DNA: DEOXYRIBONUCLEIC ACID
A very long molecule inside a cells
nucleus which usually appears as long
threads.
A molecule, shaped like a double helix,
located inside the cell nucleus
The molecule looks like a ladder, and
each rung is formed by a single base
pair

10. DNA STRUCTURE & FUNCTION
BASE PAIRS – Sequencing constitutes
the individuals or species genome.
Humans have approximately 3 Billion base
pairs. ADENINE (A) – THYMINE (T)
CYTOSINE (C) – GUANINE (G)
GENOME – the complete set of
genetic information of an individual or species
GENES – a segment of DNA that contains genetic
information required to carry out a specific job.
25000 genes determine an individual’s specific characteristics

11. ( 1 4 ) 25000 or 1 out of 1.13 x 10 15000 GENETIC DIVERSITY
Achieved by all the possible genetic variations of a particular species. The greater the population, the greater the genetic diversity.
( ) or 1 out of 1.13 x

12. CELL DIVISION
MITOSIS
MEIOSIS

13. CELL DIVISION CELL DIVISION OCCURS FOR THREE REASONS
1- TO INCREASE AN ORGANISM’S CELL COUNT, THEREBY ALLOWING THE ORGANISM TO GROW
2- TO REGENERATE DAMAGED OR BROKEN TISSUE
3- TO MAKE SEXUAL REPRODUCTION POSSIBLE
Cell division is a process that is essential to the production of new cells for the purpose of growth, tissue repair, and sexual reproduction.

14. CELL DIVISION INTERPHASE – the period when cells are not dividing
REPLICATION – the final phase of the dividing process where the DNA duplicates. The old strand breaks apart while a new (complimentary) strand attaches.
CHROMOSOMES – DNA strands coil and condense to form “rod like” structures called Chromosomes. These chromosomes are shaped like an “X” and are made up of two rods joined together at the center. Each rod is called a CHROMATID, which is an exact copy of the other. Chromosomes form pairs. One part of the chromosome contains genetic material from the mother, while the other contains genetic material from the father

15. CELL DIVISION CHROMOSOMES (cont) –
There are 23 sets of Chromosomes in the Human Genome.
The first 22 sets are numbered. The 23rd set determines the individual’s gender (XX = female, XY = male)

16. MITOSIS
A PROCESS OF CELL DIVISION IN WHICH CELLS MULTIPLY IN ORDER TO ENSURE GROWTH AND TISSUE REPAIR
RESULTS IN DIPLOID CELLS (DOUBLES) WHICH POSSESS TWO SETS OF CHROMOSOMES – ONE FROM FATHER & ONE FROM MOTHER
ALL CELLS IN HUMAN BODY ARE DIPLOID EXCEPT SEX CELLS

17. MITOSIS Phases of Mitosis Starts at the end of Interphase -
1- PROPHASE
2- METAPHASE
3- ANAPHASE
4- TELOPHASE

18. MITOSIS PHASE 1 – PROPHASE
INTERPHASE HAS ENDED – Parent cell has grown and completely replicated its DNA
DNA strands coil and condense to form chromosomes
The Nuclear membrane
disappears

19. MITOSIS PHASE 2 – METAPHASE
Chromosomes align at the center of the cell

20. MITOSIS PHASE 3 – ANAPHASE
Chromosomes split at their centers into chromatids
Chromatids move away from the center; half go to one end of the cell, the other half go to the other end

21. MITOSIS PHASE 4 – TELOPHASE A new nuclear membrane forms
DNA uncoils into separate strands
Organelles and cytosol are evenly divided
The cell divides into two daughter cells

22. MEIOSIS
THE PROCESS OF CELL DIVISION IN WHICH MALE AND FEMALE GAMETES ARE PRODUCED IN ORDER FOR SEXUAL REPRODUCTION TO TAKE PLACE
CALLED HAPLOID CELLS BECAUSE THEY ONLY CONTAIN ONE SET OF CHROMOSOMES (THAT IS ONE SET FROM EACH PAIR).
MEIOSIS I: PROPHASE I, METAPHASE I, ANAPHASE I, TELOPHASE I
MEIOSIS II: PROPHASE II, METAPHASE II, ANAPHASE II, TELOPHASE II
4 HAPLOID DAUGHTER CELLS ARE PRODUCED AT THE END

23. MEIOSIS Stages of Meiosis 1 – Prophase I 2 – Metaphase I
3 – Anaphase I
4 – Telophase I
5 – Prophase II
6 – Metaphase II
7 – Anaphase II
8 – Telophase II

24. CELLULAR SPECIALIZATION
TISSUE TYPES
FROM TISSUE TO ORGAN
FROM ORGAN TO TISSUE

25. TISSUE TYPES
A tissue is a group of similar cells that have a common structure and function.
There are four types of tissue:
Epithelial
Connective
Nerve
Muscle

26. 1) EPITHELIAL TISSUE
This tissue covers and protects organs, both inside and outside the body.
1) It protects us from the outside world - skin
2) Absorbs – stomach and intestinal lining (gut)
3) Filters – the kidney
4) Secretes – forms glands

27. CHARACTERISTICS (TRAITS):
1) Closely attached to each other forming a protective barrier.
2) Always has one free (apical) surface open to outside the body or inside (cavity) an internal organ.
3) Has no blood vessels but can soak up nutrients from blood vessels in connective tissue underneath.
4) Can have lots of nerves in it (innervated).
5) Very good at regenerating (fixing itself). i.e. sunburn, skinned knee.

28. 2) CONNECTIVE TISSUE
This tissue binds and supports tissues and organs in the body.
They protect and provide nutrients.
Connective Tissue is the most abundant and widely distributed tissue in the body.
As tendon and ligaments protects joints and attached muscles to bone and each other

30. Cartilage
Functions (jobs):
1) provides strength with flexibility while resisting wear, i.e. epiglottis, external ear, larynx
2) cushions and shock absorbs where bones meet, i.e. intervertebral discs, joint capsules

31. 1) provides framework and strength for body 2) allows movement
Bone
Functions (jobs):
1) provides framework and strength for body
2) allows movement
3) stores calcium
4) contains blood-forming cells

32. Blood
Functions (jobs):
1) transports oxygen, carbon dioxide, and nutrients around the body
2) immune response

33. 3) Nerve Tissue
Helps control and guide body activity, enabling the sending and receiving of messages from the brain to different parts of the body.
You can find Nerve tissue in the following areas:
Nerves
Spinal cord
Brain

34. 4) Muscle Tissue
Has the ability to contract and regain its shape. (similar to a spring)
Moves blood, food, waste through body’s organs
Two types of movement
Voluntarily – moving ones leg.
Involuntarily – your heart beating.

35. Three types of Muscle Tissue
Skeletal Muscle tissue:
- Attaches muscle to bone.
Smooth Muscle tissue:
- This lines the inside of organs that contract.
- Stomach, bladder, uterus, and some blood vessels.
Cardiac muscle tissue:
- Found only in and around the heart.

36. From Tissue Organ to
ORGAN: Structure composed of two or more tissue types performing one or more specific functions.
Ex. Stomach has epithelial, connective, muscle and nerve tissue. They work together to store and break down and digest food.
Other examples: Skin, heart, lungs and brain.

37. From Organ System to
SYSTEM: A group of organs and tissues working together to accomplish a common function.
Ex. Stomach works with the intestine, esophagus and other organs in the digestive system.