11. Animal Cell Specialization, Stem Cells, Tissues & Organ Systems

What is cell specialization?

• The process where cells develop specific structures and functions.

Name the 3 factors affecting cell specialization.

Name the 3 factors affecting cell specialization.

1. Cytoplasm contents,

2. environmental conditions,

3. neighbouring cells.

influence cell specialization: Cytoplasm content (WHAT’S INSIDE THE CELL)?

• Even when cells divide:?

• ex?

1⃣ Cytoplasm content (WHAT’S INSIDE THE CELL)

Even when cells divide:

• DNA is the same

• Cytoplasm is NOT always the same

Example:

• One cell gets more vacuoles (energy storage)

• That cell grows bigger or stronger

🧠 This helps decide what the cell becomes

Influence Cell specialization: Environmental conditions (WHERE THE CELL IS)

• Things like?

• ex?

2⃣ Environmental conditions (WHERE THE CELL IS)

Things like:

• Temperature

• Nutrients

• Chemicals

Example:
🐱 Siamese cats

• Cold areas → dark fur

• Warm areas → light fur

Same genes. Different environment.

3⃣ Influence Cell Specialization: Neighbouring cells (WHO IS AROUND IT)

Nearby cells do what?

Example: ?

3⃣ Neighbouring cells (WHO IS AROUND IT)

Nearby cells:

• Release chemicals

• These chemicals tell the cell what to become

Example:
👁 Eye development in specific location in a chick embryo

• Only forms where certain cells are nearby

⚠ Abnormal cell development

If something goes wrong:?

Cells can: ?

FACT:?

⚠ Abnormal cell development

If something goes wrong:

• Chemicals

• Pollution

• Disease

• parasites

• Temperature changes

Cells can:
❌ Develop incorrectly

FACT:
👉 ~90% of embryo problems are caused by environmental factors

tissue = ?

tissue = a group of similar cells doing the same job

🌱 STEM CELLS

• What is a stem cell?

🌱 STEM CELLS (VERY TESTABLE) What is a stem cell?

A cell that:
👉 has no job yet
👉 can become other cells

Like a blank character in a video game 🎮

Types of stem cells

---

Totipotent?

(order?)

Types of stem cells (ORDER MATTERS)

---

1⃣ Totipotent (EARLIEST)

• early in human devolopment

• Found in embryos

• Can become ANY type of cell in body

🧠 Most powerful

Pluripotent?

order?

2⃣ Pluripotent

• embryo develops, stem cell beocomes pluripotent

• less versatile, still many options

• cannot produce every cell type

Types of stem cells ORDER?

Types of stem cells (ORDER)

---

1⃣ Totipotent (EARLIEST)

2⃣ Pluripotent

3⃣ Adult Stem Cells (AFTER BIRTH)

Adult Stem Cells ?

order?

3⃣ Adult Stem Cells (AFTER BIRTH)

• late in development after birth

• people only have adult stem cells

• Limited

• Repair only specific tissues

Examples:

• Skin stem cells → skin

• Bone stem cells → bone

why stem cells matter they can: ?

Why stem cells matter

They can:

• Replace damaged cells

• Help treat diseases

Hierarchy - ?

• based on

(can live on their own since they do not depend on any other cells.)

🪜 HIERARCHY (LEVELS OF ORGANIZATION)

MEMORIZE THIS ORDER ⬇

CELL (bottom)
⬇
TISSUE
⬇
ORGAN
⬇
ORGAN SYSTEM
⬇
ORGANISM (top)

There are only four main types of tissue: ?

There are only four main types of tissue:

1. epithelial,

2. muscle,

3. nervous,

4. and connective.

: Why are embryonic stem cells controversial?

• Embryonic stem cells are obtained by destroying embryos

• Some people believe embryos have a right to life

• Raises questions about:

  • when life begins

  • consent

  • how stem cells are harvested

🧠 Potential Benefits of Stem Cells

Stem cells?

🧠 Potential Benefits of Stem Cells

Stem cells:

• Can replace damaged or diseased cells

• May help treat conditions such as:

  • spinal cord injuries

  • diabetes

  • Parkinson’s disease

• Are valuable for medical research because they can become many cell types

Q: Why can cells with the same DNA become different??

• Because different genes are turned on or off due to

• cytoplasm contents,

• environmental conditions,

• and neighbouring cells.

1. Nervous System

Q: Function of the nervous system?

Organs: Brain, spinal cord, nerves

1. Nervous System

Controls and coordinates body activities; responds to stimuli.

Organs: Brain, spinal cord, nerves

1. Nervous System

Q: Function of the nervous system?

Organs:

2. Circulatory System

Transports oxygen, nutrients, hormones, and removes wastes.

Organs: Heart, blood, blood vessels

3. Respiratory System

Q: Function of the respiratory system?

Organs:

3. Respiratory System

Gas exchange (oxygen in, carbon dioxide out).

Organs: Lungs, trachea, bronchi

4. Digestive System

Q: Function of the digestive system?

Organs:

4. Digestive System

Breaks down food and absorbs nutrients.

Organs: Stomach, small intestine, large intestine, esophagus

5. Urinary (Excretory) System

Q: Function of the urinary system?

Organs:

5. Urinary (Excretory) System

Removes liquid wastes and regulates water balance.

Organs: Kidneys, bladder, ureters

Skeletal System

Q: Function of the skeletal system?

Organs: ?

Skeletal System

Supports the body and protects organs; allows movement.
Organs: Bones, cartilage, ligaments

Muscular System

Q: Function of the muscular system?

Organs:

Muscular System

Enables movement and helps circulate blood.

Organs: Skeletal muscles, smooth muscle, cardiac muscle

integumentary System

Q: Function of the integumentary system?

Organs:

ntegumentary System

A: Protects the body and prevents water loss.
Organs: Skin, hair, nails

Endocrine System

Q: Function of the endocrine system?

Organs:

Endocrine System

Produces hormones that regulate body processes.

Organs: Glands (pituitary, thyroid, adrenal, pancreas)

Endocrine System

Q: Function of the endocrine system?
Organs:

Lymphatic (Immune) System

A: Defends the body against disease and infection.

Organs: Lymph nodes, spleen, white blood cells

Reproductive System

Q: Function of the reproductive system?

Organs:?

Reproductive System

• Produces offspring.

Organs:

• Male: Testes

• Female: Ovaries, uterus