A&P Exam 1

Chapters 1-5 (The human body, chemistry, cells: plasma membrane, tissues, integument)

Anatomy

The various structures of the body and their relationship to one another

Gross anatomy

The study of body structures that can be seen with the naked eye, including organs and organ systems

Microscopic anatomy

The study of body structures at the cellular and tissue level; requires a microscope to observe

Physiology

How the individual body parts function on a normal level, most often considered at the cellular level

Relationship between anatomy and physiology

Physiology is dependent on anatomy

Structural organization of the human body (least to most complex)

Chemical level, cellular level, tissue level, organ level, organ system level, organismal level

Chemical level

Atoms combine to form molecules

Cellular level

The smallest unit of life

Tissue level

Aggregations of living cells that carry out a similar function

Organ level

Two or more tissues operate together to perform a certain function

Organ system level

Multiple organs work together to accomplish a purpose (bodily function)

Organismal level

All organ systems working together to keep the organism alive

Necessary life functions

Maintaining boundaries, movement, responsiveness/excitability, digestion, metabolism, excretion, reproduction, and growth

Maintaining boundaries

At the cellular level (cell membrane), and at the organismal level (skin)

Movement

Cooperation of skeletal and muscular systems to coordinate actions. Can be conscious movements or not

Examples of movement (life function)

Skeletal muscle tissue (voluntary), cardiac muscle tissue (involuntary), and smooth muscle tissue (involuntary)

Responsiveness (Excitability)

Sensing environmental changes and responding to them

What is primarily involved with excitability?

The nervous system

Digestion

Food is broken down into simple molecules to be absorbed into the blood and spread throughout the body

Metabolism

The sum of all the chemical reactions that take place in the body

Catabolism

Breaking down into smaller parts

Anabolism

Building up from smaller parts

Cellular respiration

Chemical reactions that lead to the production of ATP

ATP

The energy molecule of the cell

Excretion

Removal of waste produced during digestive and metabolic processes

How does nitrogenous waste get excreted?

Via kidneys and urinary tract

Reproduction on the cellular level

Cells must divide in order for an organism to live. This is for overall maintenance of the organism

Reproduction on an organismal level

Production of offspring, not necessarily required

Growth

Increase in the number of body cells

What needs to happen in order to grow?

There needs to be more anabolic than catabolic reactions

Survival Needs

Resources needed for your body to carry out the necessary life functions

What are the survival needs?

Nutrients, oxygen, water, endothermy, atmospheric pressure

How do we get nutrients?

Bring them into our body by ingestion

What are considered nutrients?

Carbs, fats, proteins, vitamins, minerals

How long can the average body cell survive without oxygen?

3-4 minutes

How much of our body weight is water?

60%

Where is most of the water in our body found?

In cells

What does water provide?

An environment for chemical reactions and serves as a fluid base for secretion and excretion

What is the base of every single body fluid/secretion?

Water

Endothermy

Body temperature must be maintained for chemical processes to occur

What is the average internal body temperature?

98.6ºF

Atmospheric pressure

Breathing and gas exchange occur at an appropriate atmospheric pressure

Homeostasis

The maintenance of the internal body condition despite a constantly changing external environment

Is homeostasis static or not static?

Not static

What is homeostasis regulated by?

The nervous and endocrine system

3 parts/mechanisms involved in variable control/regulation

Receptor, control center, effector

Receptor

The starts of the message and what gets sent to the control center

Control center

Central nervous system, mainly brain but sometimes spinal cord

Endocrine system

Glands that produce and release hormones

Effector

The organ that carries out the change that needs to be made

How is homeostasis controlled?

Through negative or positive feedback mechanisms

Negative feedback mechanism

Mechanism that causes the variable to change in a direction that is opposite of the initial change

Negative feedback mechanism example

Sweating → when you get too hot you start to sweat but once you cool down the sweating stops

Positive feedback mechanism

Causes the original change of the variable to be enhanced

Positive feedback mechanism example

Breastfeeding → baby sucks on the nipple and stimulates mammary glands to produce milk, which then the baby drinks and continues stimulating the mammary gland

Imbalances in homeostasis

Aging and autoimmune disease

Autoimmune disease

Cascade of events caused by positive feedback mechanisms can overpower negative feedback mechanisms

Anatomical position

Right and left in terms of the person being observed with palms facing us

Dorsal (posterior)

Back side

Ventral (anterior)

Front/belly side

Lateral

Further away from the midline of the body

Medial

Closer to the midline of the body

Distal

Further away (when relating 2 things)

Proximal

Closer (when relating 2 things)

Deep

Further away from the body surface (skin)

Superficial

Closer to the body surface (skin)

What is the most superficial organ?

Skin

Superior

Top (when relating 2 things)

Inferior

Bottom (when relating 2 things)

Sagittal (median/midsagittal) body plane

Divides the body into left and right halves

Frontal

Divides the body into anterior and posterior

Transverse

Divides the body into superior and inferior parts

Body cavities

Fluid-filled spaces inside the human body that hold, protect, and separate internal organs

Dorsal body cavity

Protects organs of the CNS

What is the dorsal body cavity composed of?

The cranial cavity and spinal cavity

Ventral body cavity

Houses visceral organs

What is the ventral cavity composed of?

The thoracic cavity and abdominopelvic cavity

Thoracic (Chest) Cavity

Contains the heart and lungs

What is the thoracic cavity protected by?

The ribs

Abdominopelvic cavity

Every other visceral organ, not protected by bone

What separates the thoracic and abdominopelvic cavity?

The diaphragm

What are the cranial and vertebral cavities enclosed by?

Bones

Serous membrane (serosa)

Double-layered membrane, folds in on itself to form 2 membranes

Visceral layer

Innermost layer covering the organ

Parietal layer

Outer layer lining the body wall of the cavity

What are the 2 layers separated by?

Serous fluid

Why is serous fluid important?

It creates a slippery texture so the layers can slide when the organ moves

What happens if there is no serous fluid?

The 2 layers would rub against each other and rub away

How are serous membranes named?

According to their location

Pericadium

Serous membrane surrounding the heart

Pleura

Serous membrane surrounding the lungs

Peritoneum

Serous membrane surrounding most organs of the abdominopelvic cavity

Mixtures

Any substance containing 2 or more components physically intermixed

Types of mixtures

Solutions, colloids, suspensions

Solutions

Homogeneous mixtures that can exist as solids, liquids, or gases, composed of very small particles that do not settle out

Solvent

The dissolving media

What is the body’s primary solvent?

Water

Solute

The thing dissolved in the solvent

Colloids

Heterogeneous mixtures composed of large solute particles that do not settle out

Sol-gel transformation

A mixture that can change from a fluid to a more solid state