Immune System- Fights Pathogens

1. Barriers that keep pathogens out

• Skin

• Breathing Passages

• Mouth and Stomach

2. Inflammatory Response

• White Blood Cell

• Inflammation

• Fever

3. Immune Response

• T Lymphocyte

(T cell)

• B Lymphocyte

(B cell)

The Nervous System

• Receives information

• Directs your body to respond to the information.

• Helps maintain homeostasis.

General Information about the Nervous System.

• The Neuron- Cell that makes up Nerves.

• Nerves- Carry information.

• Nerve Impulse- Message ( electrical signal) carried by the neuron.

• Synapse- Junction (gap) between neurons.

• 3 types of neurons: sensory, interneuron and motor.

Nervous System

• Central- control center of the body.

• Includes Brain and Spinal cord

• Peripheral- Nerves that branch out from the central nervous system to the rest of the body.

• It is involved in voluntary and involuntary actions.

Endocrine System-Functions

• Produces chemicals called hormones that control many of the body’s activities.

• Regulates long term changes such as growth and development.

Hormones

• Chemical product of endocrine gland, that regulates activities in tissues and organs.

• Travels in the bloodstream until it reaches its specific organ. These organs have target cells that are recognized by hormones.

Endocrine Glands

• Produce and release hormones into the bloodstream.

• They control activities such as growth, blood pressure, levels of glucose, etc.

Negative Feedback

When the amount of a certain hormone in the blood reaches a certain level, the endocrine system sends a signal to stop the release of that hormone.

Reproduction in Organisms

Sexual Reproduction- Involves two parents.

Asexual Reproduction- Involves one

parent.

Reproduction in Organisms

DNA

• Carry Hereditary information.

• Looks like a twisted ladder called a double helix.

Gene- Section of the DNA responsible for a trait.

Chromosome- A rod Shape structure, located in the nucleus that carries DNA.

Chromosome Theory of Inheritance

Traits are passed on from one generation to the next through chromosomes.

Mutation- Damage in the DNA. Cancer begins when mutations affect the normal cell cycle, causing cells to divide in an uncontrolled way.

Mitosis• A cell divides to produce two

cells.

• Each daughter cell gets an identical copy of the DNA.

• Mitosis is used for growth and repair in multi-cellular organism.

• Mitosis is used for reproduction in unicellular organisms like bacteria and multicellular organisms like a potato plant.

Meiosis

Cells divide to produce four sex cells. Each sex cell has half of the DNA of the parent.

Male and Female Reproductive System

• Involves the production of sex cells or gametes.• Egg- Female sex cells• Sperm- Male sex cells• Fertilization- when the egg and the sperm join

together.• Zygote- Fertilized egg.• Human body cells have 46 chromosomes.• Human sex cells have 23 chromosomes.

Male Reproductive System

• Produces sperm and testosterone.

• Includes testis, scrotum and penis.

Female Reproductive System

• Produces eggs.

• Nourishes the developing babies until birth.

• The organs of the female reproductive system are the ovaries, the uterus, the fallopian tubes, and the vagina.

Menstrual Cycle1. An egg develops in the ovary.

2. The uterus prepares for the embryo and tissue builds up in the uterine wall.

3. If the egg is fertilized it attaches to the uterus where it develops until birth.

4. If it is not, the extra tissue and blood pass out of the body in a process called menstruation.