Bio Principles Lecture Final Exam

How large is the brain and how much resources does it take up?

Only 2% of body weight but it takes up 28% of our oxygen and 15-20% of our blood flow.

White matter is made of…

Axons

Gray matter is made of…

Cell bodies

What makes up the brainstem?

The cerebellum, pons and medulla

Cerebellum function

Coordinates body movement

Pons

Huge conduit of nerve fibers

Medulla function

Basic, non-voluntary reflexes like breathing

Reflex description

Sensory neuron synapses with interneuron in spinal cord and motor neuron responds and signals reflex (like a knee jerk)

Rods

Photoreceptors sensitive to LOW/DIM light

Cones

Photoreceptors that respond to bright lights and come in 3 colors, red, blue and green

Frontal lobe

Final place for neuronal development
- Personality, character, overall higher thinking

Temporal lobe

Auditory cortex for hearing

Parietal lobe

Mulitsensory areas
- Includes speech and reading

Occipital lobe

Contains visual processing center

Simple cuboidal epithelial cells

Line the kidneys to reabsorb water

Simple columnar epithelial cells

Lines the small intestine
- They are long and function in absorption

Loose connective tissue

Holds skin in place and supports internal organs and blood vessels

Adipose cells

Each have a fat droplet attached

What does weight loss do to adipose cells?

Reduces the size of the attached fat droplets

White adipose cells

Makes up 20% of body weight, provides insulation and energy storage, too much causes obesity

Brown adipose cells

1% of body weight, important for brown fat and blood sugar control

Fibrous connective tissue

Bundles of collagen fibers

Tendons

MUSCLE to BONE

Ligaments

BONE to BONE

4 processes of digestion

1. Ingestion

2. Digestion

3. Absorption

4. Elimination

Amylase

Breaks down complex carbohydrates

Lipase

Breaks down fat

Bolus

Chewed up food moving down esophagus

Digestion

Hydrochloric acid in stomach is made and released by specific cells
- Pepsin, amylase and lipase are also present

Where does absorption occur?

The small intestine

What is the final stage of digestion?

Absorption in the duodenum

Duodenum

First part of small intestine where bile breaks down fat and pancreatic enzymes break down sugars and starches

Jejunum

First stage of absorption

Ileum

Absorbs certain vitamins

Large intestine

Reabsorbs around 90% of fluid, and undigested material is excreted

Normal RBC count

4.7-6.1mil per liter of blood

Normal WBC count

5-10k per microliter of blood

Leukemia

Low white blood cell count

High WBC count indicates…

Sickness

What does bone marrow have?

Hematopoietic stem cells that become red and white blood cells

What do granules in white blood cells contain?

Proteins, enzymes, and histamines

What makes immune cells special?

They can move via amoeboid movement

How are foreign invaders recognized?

Antigen protein marker on the surface of the invader differs from our cells

What do antibiotics do?

They match the protein receptors of their targets

Which leukocytes circulate in the blood stream?

Neutrophils, monocytes and lymphocytes

Mast cells

Found in all cell tissues, when they are damaged, they initiate an immune response

Nonspecific (immediate) inflammatory response

Mast cells are ruptured which causes degranulation and the release of histamine

What does histamine do?

Causes vasodilation at site of infection and vasopermeability which makes holes in blood vessels for specific leukocytes to diffuse

Neutrophils

Attack via phagocytosis

Monocytes

Exposure to foreign antigens transforms them into macrophages that swallow a large amount of bacteria

Pus

Dead leukocytes

What else can macrophages do?

They can swallow some bacteria and become an antigen presenting cell which goes to the nearest lymph node

Delayed Specific Immune Response

Macrophage swallows some bacteria and presents antigen to lymphocytes to create many specific lymphocytes and some memory cells

Bacteria

Prokaryotic unicellular organism with no inner membrane

Plasmid

Circular bacterial DNA that is antibiotic resistant and transferred via the sex pilus

Antibiotic resistance

When bacteria protein receptors have evolved so the same antibiotics don’t work

Bacteria shapes

Rods, coccus and spirochete

Methods of bacterial infection

• Ingestion

• Cuts

• Airborne

• Inanimate objects

Endotoxins

Secreted by bacteria when attached, they punch holes in cells to leak cytoplasm for bacteria to feed on
- Only affects the area where they are injected into

Exotoxins

Secreted by bacteria into bloodstream to circulate through the body

Fever

Immune response induced by pyrogens after many leukocytes die to hype up the immune system to produce more leukocytes and increased heat kills bacteria

Virus

Non-living, non-mitotic, no cell wall, no organelles, non-growing, and extremely small

Capsid

Protein coat that contains virus DNA

Main categories for viruses

Single/Double-stranded
DNA/RNA

RNA viruses

They contain RNA and an enzyme called reverse transcriptase

Non-enveloped viruses

Can remain outside for a long time

Enveloped viruses

Require intimate contact to transfer

What do viruses do?

They are tissue specific and inject their DNA into our cells so we replicate their DNA

What does reverse transcriptase do?

RT converts viral RNA into DNA which enters the nucleus and tells it to make so much RNA that the cell bursts