Tobacco

Exploring the Effects of Tobacco

Plant and Human Structure and Function

Plant Cells• Plant cells have a cell wall.• Plant cell structure is for function

(example: sieve tube members have a structure for special for transportation and mesophyle cells have increased number of chloroplasts for photosynthesis)

• Rarely expand equally in all directions• Some of the major types of plant cells

include– Parenchyma– Collenchyma– Sclerenchyma– Water-conducting cells of the xylem– Sugar-conducting cells of the phloem

Plant Seeds• Reproduction

• Dicots – two seed coats (beans)

• Moncots – one seed coat (corn)

Plant Roots• Root hairs (lateral growth of

roots)• The primary growth of roots• – Produces the epidermis,

ground tissue, and vascular tissue (meristems – cells are dividing)

• Gravitropism – Growth in response to gravity

• In most plants – The absorption of water and minerals occurs near the root tips, where vast numbers of tiny root hairs increase the surface area of the root

Plant Stems• A stem is an organ consisting of –

An alternating system of nodes, the points at which leaves are attached which functions as support, transport and storage.

Water-conducting cells - xylemSugar-conducting cells - of the

phloem• Primary Growth – Apical

Meristems• Secondary Growth – Lateral

Growth

Plant Leaves• Stomata – Gas exchange• Mesophyll – Photosynthesis• Waxy Cuticle – Water

Conservation

Survival – Food Storage and Production and Gas Exchange

• Photosynthesis - Creating sugar from carbon dioxide, water and sunlight. (later)

• Modified stems and roots (bulbs (onion), tubers (potato), cabbage)

• Gas Exchange – Through stomata in leaf. Oxygen is given off during photosynthesis. (later)

Survival Protection

• Toxins – Nicotine Production (Topic for later)

How do plants defend themselves?• Mechanical defense: Waxy cuticle (prevents

bacteria and fungus), hairy or sticky leaves, Spines (thorns and prickles)

• Chemical Defense: Powerful drugs and poisons (e.g. caffeine, nicotine, cocaine, morphine, etc.)

Plant Reproduction

• Seeds

• Flowers

Gas Exchange

The stomata are openings in the leaf that allow gas exchange with the atmosphere.

CO2 is taken in and O2 is given off. CO2 is used in production of sugars and O2 is produced from the split of water.

Photosynthesis

-The light reactions use light energy to make ATP and NADPH.

-The Calvin cycle uses the energy molecules from the light reactions to convert CO2 into sugar

Environmental Response

• Tropism (Directional growth in response to stimulus) – Phototropism (response to light), Gravitropism (response to gravity), Thigmotropism (contact), Heliotropism (solar tracking), hydrotropism (water)

• Hormones (chemical messengers that regulate growth and development) – Auxins (cell elongation), Gibberellins , Cytokinins, Ethylene, Abscisic acid.

Tobacco Plant

• Nicotiana tabacum

• Nicotine is used as the plants defense

Effects of Tobacco on the Human Body

HomeostasisTo maintain homeostasis, organisms

actually must make constant changes. That is why homeostasis is often referred to as maintaining a dynamic equilibrium. Dynamic means “active,” and equilibrium means “balanced.”

• Homeostasis requires active balancing.

• Positive Feedback – Something stimulates a positive behavior (child birth)

• Negative Feedback – Something stimulates a negative response (temperature control)

Respiratory system

• Gas exchange in lungs(O2 from air enters the blood stream and CO2 is expelled.)

• Tobacco use – lungs increase in tar creates emphysema (alveoli rupture)

Nervous System

• Nervous system • Central Nervous system( brain

and spinal cord) and Peripheral Nervous system (nerves and synapse )

• Autonomic (sympathetic and parasympathetic ) and Voluntary muscles (under control)

Tobacco Use • Dopamine Production in brain

stimulates and depresses limbic system and emotions.

• Extremely addictive

Endocrine System

• The nervous and endocrine systems both work together to cause animals to adapt to their environment.

• A system of glands and hormones makes up the endocrine system. The key function of this important system is maintaining homeostasis.

• The endocrine glands produce hormones, chemical messengers that are released into the blood and carried throughout the body by the circulatory system.

• Tobacco – Increase hormone production and pancreas cancer.

Digestive System

• From the mouth to the anus food is broken down and absorbed by the epithelial cells.

• Tobacco causes decay of teeth, mouth and throat cancer.

• Tobacco also causes kidney, stomach and bladder cancer.

Reproductive System• The male reproductive system

has two main functions: It produces haploid male gametes, the sperm cells; and it must be able to deposit the sperm cells it produces inside the female.

• Three important functions are performed by the female reproductive system.

• First, gametes (eggs) are produced in the ovaries.

• Second, a pathway is provided for sperm cells to reach an egg. Third, the female reproductive system provides a temporary home for the developing embryo.

Cigarette smoke causes problems/complications in pregnancy and child birth.

Immune System• The immune system defends our

bodies against very specific microscopic invaders.

• The immune system helps maintain the internal dynamic equilibrium necessary for life.

• immunity—the ability to resist an infection—by preparing it to fight subsequent invasions by the same microbes (by producing the appropriate antibodies)

• First line of defense - skin• Second line of defense – inflamation• Internal Specific lines of defense – B

cells and T cells (white blood cells)

Tobacco Use Summary• Toxin created by plants as a defense against

herbivores.• Human use includes botanicals (pesticides), mouth

chew, cigarettes smoking, and snuff.• Causes cancer in the mouth, throat, stomach, lung,

kidney and other systems.• Causes complications in the reproduction process.• Causes coronary artery disease and an increase heart

disease.• Causes chronic bronchitis and emphysema (decrease

of O2 from lungs)• Cigarette advertising was banned in US in 1971

because of increased awareness.