Bio - Unit 7 - The Human Body

A healthy person is able to maintain blood sugar homeostasis after eating a meal and after short periods of fasting.

After a meal, a person's blood sugar level is elevated. The pancreas releases insulin, which signals the body to store glucose. The liver stores excess glucose in the form of glycogen and blood glucose levels are restored to normal levels. This provides feed back to the pancreas to reduce insulin production, and blood sugar levels stabilize. If a person hasn't eaten in a while, the pancreas releases glucagon, which signals the body to release stored glycogen. The liver converts glycogen to glucose and blood sugar increases accordingly.

The peripheral nervous system can be divided into the autonomic nervous system and the somatic nervous system.

Autonomic controls involuntary internal functions, including cardiac muscle contractions and smooth muscle contractions. The autonomic nervous system can be further divided into the sympathetic and parasympathetic systems. The sympathetic nervous system controls the fight or flight response and the parasympathetic system maintains homeostasis, sometimes called the rest and digest function. Somatic controls skeletal muscles, directs voluntary movements and reflex arcs.

Explain bone remodeling and the three types of bone cells involved in this process

Bone remodeling is the process of bone being built up and broken down over time. Bone remodeling is required for strong, healthy bones. Osteoblasts are the cells that build new bone tissue. Once osteoblasts are trapped inside the bone they have built, they are called osteocytes. Osteoclasts are bone cells that break down bone tissue.

Compare and contrast the humoral immune response and the cell-mediated immune response. How do vaccines stimulate each of these responses?

Both the humoral and the sell-mediate immune response are parts of the immune response and specific defenses against pathogens. The humoral immune response primarily uses B cells, which produce antibodies against specific antigens. The cell-mediated immune response primarily uses T cells to recognize foreign antigens. Vaccinations work on both the humoral and cell mediated immune responses, stimulating the production of both memory B cells and memory T cells. This facilitates a rapid response against infection

Vitamin A deficiency

Can lead to vison problems, among other symptoms

The hard tissue on the outside of the bone is

Compact

Emphysema

Damaged alveoli due to weakening and tearing of alveolar tissue

Beginning with deoxygenated blood from the body being returned to the heart, how does blood flow through the heart?

Deoxygenated blood enters the heart through the superior vena cava and inferior vena cava to enter the right atrium. The right atrium pumps blood into the the right ventricle through the tricuspid valve. The right ventricle then pumps the blood through the pulmonary artery to the lungs, where it is oxygenated Oxygenate blood returns to the heart, passing through the pulmonary vein to enter the left atrium. The left atrium pumps the blood through the mitral valve into the left ventricle. Finally, the left ventricle pumps oxygen-rich blood through the aorta to the entire body to deliver oxygen and pick up carbon dioxide and other waste.

Human skin consists of 3 layers.

Epidermis - Contains the structural protein keratin and the pigment melanin. Melanin gives skin its color and absorbs ultraviolet radiation from the sun Dermis - Regulates body temperature with blood vessels that expand or constrict as necessary. The dermis also has mechanoreceptors to mediate touch and sebaceous glands that secrete an oily substance called sebum Hypodermis - consist of connective tissue and fat that stores energy, insulates the body, and cushions the body

Digestion in humans begins in the mouth and continues throughout the digestive system. What are the steps in the correct order?

In the mouth, the teeth and tongue begin mechanical digestion if food and enzymes like amylase and lysozyme begin the chemical digestion of food. The epiglottis separates the mouth from esophagus. Peristalsis, a pattern of muscle contraction, moves the chewed food, now called bolus, through the esophagus and into the stomach. In the stomach, mechanical digestion continues with the stomach churning and chemical digestion continues with pepsin and hydrochloric acid. After the stomach, the mixture of food and digestive enzymes, called chyme, enters the first part of the small intestine, called the duodenum, where it is mixed with digestive enzymes and digestive fluids from the pancreas and gallbladder. The second and third parts of the small intestine, the jejunum and the ileum, are where the majority if nutrients are absorbed into the bloodstream. The jejunum and ileum have projections called villi and microvilli to maximize nutrient absorption. After the small intestine, the large intestine absorbs water from the remaining material and anything left serves as a food source for the bacteria that live in the intestine before the waste material is excreted through the anus.

Compare and contrast the fats found in butter, olive oil, and margarine. What types of fats are primarily found in each of these foods, an what is their structure? How do these fats impact t=human health?

Most dietary fats are triglycerides. A triglyceride contains a glycerol molecule attached to three fatty acids. These three foods have different compositions of fatty acids. Butter contains mostly saturated fatty acids. These fatty acids have only single bonds between carbon atoms, and the carbon atoms are "saturated" with hydrogen atoms. Saturated fatty acids form a straight chain and pack together well, making butter solid at room temperature. Consuming too much saturated fat can be associated with high cholesterol levels. Olive oil contains mostly unsaturated fatty acids. These fatty acids have at least one double bond between carbon atoms, which creates a bend in fatty acid structure. This causes the fatty acid to not pack together as tightly, and foods containing these fats typically remain liquid at room temperature. Naturally occurring unsaturated fats, like those in olive oil, are typically in the cis conformation, with carbon atoms in the double bond on the same side of the double bond. Unsaturated fats help raise good cholesterol. Margarine primarily contains trans fats. These fats are unsaturated but synthetic, with the carbon atoms on either side of the double bond on opposite sides of each other. Trans fats have no health benefits for humans and are associated with heart disease, obesity, and other diseases.

A person hiking in the woods brushes against a thorny bush and is scratched. Name two ways the components of the person's blood prevent or fight an infection from the scratch.

Platelets, also called thrombocytes, are cell fragments that help blood clot to heal wounds. Platelets stick to the wall of the blood vessel to form a platelet plug and help form a clot. White blood cells, also called leukocytes, are a part of the immune system. They identify infectious pathogens that might have entered the body through the scratch.

When a neuron isn't being stimulated, it is mor negatively charged on the inside of the cell than the outside. This is its

Resting potential

Optic Nerve

Route by which signals are transmitted from the eye to the brain.

You hear a loud noise and move your head to see what made he noise. At the level of neurons, describe how your ear senses the sound, how information regarding the noise is transmitted from your ear to your brain, and how the brain directs your movement. Include the role of the brain, mechanoreceptors, motor neurons, neurotransmitters, and sensory neurons in your answer.

Sounds enter the ear as vibrations that cause the eardrum to vibrate, moving tiny bones in the middle ear and causing vibrations in the inner ear. Mechanoreceptors in the cochlea sense vibrations. Sensory neurons send messages to the brain to process the sound. For a nervous impulse to travel to the brain, each neuron fires an action potential in which the neuron is depolarized buy opening sodium channels. Sodium channels all the way down the long axon of the neuron open, transmitting the signal. At the synapse between two neurons, neurotransmitters relay the message. After the brain has processed the sound, it sends messages via motor neurons to cause the head to move. Again, actional potentials and neurotransmitters are used to transmit this signal.

Testosterone is a hormone with a chemical structure. Is testosterone a steroid hormone, and why? How does testosterone work?

Testosterone is a steroid hormone because its structure is cholesterol-based. This means that it is lipid-soluble, so it can cross the cell membrane to enter target cells. Testosterone exerts its effects inside a target cell by binding testosterone receptors.

Chronic obstructive pulmonary disease

Tissue group of diseases characterized by inflammation of the lungs and airways over time.

The sodium-potassium pump is an example of ________ that restores the resting potential.

active transport

During digestion, proteins are broken down to form ________

amino acids

Cartilaginous joints

bones are connected by cartilage, which allows a small amount of movement. Joints between vertebrae.

Fibrous joints

bones held together by fibrous connective tissue. Most fibrous joints are immobile or have minimal movement. Examples: joints connecting the bones of the skull and the joints connecting teeth in their sockets

Vitamin D deficiency

can cause Rickets disease, involving soft, weak, and deformed bones.

Iodine deficiency

can cause goiter as well as thyroid problems.

Vitamin C deficiency

can cause scurvy, which can result in gum problems, poor wound healing, and fatigue

The spongy tissue on the inside of the bone is

cancellous

The short hair-like structures on the surface of the cells in the nasal cavity, trachea, and bronchi is the

cilia

Asthma

constriction of airflow due to tightening of muscles around airways and swelling of airways

The muscle beneath the lungs and ribs that contracts and flattens to allow breathing is the

diaphragm

An amino acid that the body can't synthesize and must obtain through the diet is call a/an __________acid

essential

Animals use _______ for short-term energy storage

glycogen

Synovial joints

have a space filled with synovial fluid between bones, which helps absorb shocks and reduce the friction generated by movement. These joints allow the most range of movement. The human body has six different types of synovial joints, each of which allows a different type of movement.

Red blood cells are able to bind oxygen because they contain

hemoglobin

Bronchitis

inflammation of bronchi

Iron deficiency

is called anemia, which can cause fatigue and weakness

The site of the vocal cords and the upper part of passsage from the throat to the lungs is the

larynx

A primary component of cellular membranes are

lipids

Inside the hollow parts of bones is a fatty tissue called

marrow

Some neurons have a/an ______ allowing neurotransmission to be more efficient.

myelin sheath

the cells that build new bone tissue are called

osteoblasts

The cells that break down bone tissue are called

osteoclasts

The fluid portion of blood is calles

plasma

Thrombocytes are cell fragments that help with blood clotting and are also referred to as

platelets

Pneumonia

presence of fluid in alveoli, often due to bacterial or viral infection

Immediately after an action potential is fired, sodium channels are closed and the cell can't fire another action potential, called the

refectory period

Iris

regulates the amount of light that enters the eye through the pupil.

Hinge joints

such as elbows and knees, can bend and extend. Ball-and-socket joints, such as hips and shoulders, can move in multiple directions and can also rotate. Gliding joints, condyloid joints, pivot joints and saddle joints are other types of synovial joints.

Sucrose and lactose are disaccharides because they consist of two ______

sugar molecules

Neurotransmitters are released into the ______ when vesicles fuse with the presynaptic membrane

synapse

Retina

the surface at the back of the eye where rods and cones reside that detect visible light.

Cornea

the transparent front of the eye that, along with the lens, focuses light as it enters the eye.

The lower part of passage from the throat to the lungs that splits into the bronchi is the

trachea

Dietary fats are primarily in the form of

triglycerides

The component of blood that helps fight infections is

white blood cells