Bsc 1010 Exam 2 Preparatory Notes

2/1/18
Bio Principles Lecture
Unit 2
CHAP 6 (Cells)
Rule of Thumb:3
Question 1: How long can you survive without water?
- 3 days
Question 2: How long can a human survive without food?
- 3 weeks
Question 3: How long can you survive without oxygen?
- 3 minutes
Digestive System
 Define: How animals obtain food to survive
 How does the digestive system feed the cells in the body?
-by the blood stream
 Food that is being digested is being broken down
 The intestines are surrounded by capillaries (blood vessels), all the nutrients are
being diffused into the vascular system and then to the rest of the body
 Villi- finger like projections present in the intestines
 Nutrients absorbed from small intestine are transported throughout the body in
the bloodstream.
 Every single cell in the body has to obtain food
 Red Blood Cells carrying oxygen from the lungs and taking Co2 and releasing it,
CO2 as a result being toxic, RBC binds to the CO2
- Oxygen being brought to cells and Co2 is being taken away
 The cells push the cellular waste into this space and they find their way to the lymphatic
system or circulatory system
 Cells produce chemicals and toxins

3. Why do animals eat?
Ingests and breaks down food so that it can be absorbed by the body
Ex: A strawberry is digested the food molecules (sugar) will go to the
mitochondria producing atp(energy) powering all the cells.
3. What does the heart do?
Enables the transport of nutrients, gases, hormones, and wastes to and from all
the cells of the body
 Blood is muscular and has the job of pumping blood and everything that’s
dissolved in it – nutrients, gases, hormones, and wastes
 Blood is part of cardiovascular system

, 3. Why do we breathe?
 Enables gas exchange, supplying blood w/oxygen and removing carbon
dioxide.
 Blood is oxygenated in the blood
 If the heart fails, the lung fails have an interlinking connection
3. Why do animals urinate?
 Elimination of liquid wastes; regulation of water balance.
 Excreting cellular waste through the kidneys, filtering it out
through the urine.
 The kidneys also regulate the amount of water one will have,
keeps the correct amount of water in the body
 If one doesn’t drink enough water the kidney will suffer as we
always need to be flushing out the cellular waste
 Cellular WasteKidneysUrine

Paramecium (Protozoa)
 Made of one cell, all identical
 Gas exchange occurs through the mitochondria, where cellular respiration
will take place

3. Summary
1. We eat so that cells have nutrients
2. We breathe so that cells have oxygen
3. we urinate to excrete cellular wastes-
- feces is the waste from food that you eat
- cellular waste leaves the body through the kidneys
4. Blood carries nutrients and oxygen to all cells and removes wastes and
carbon dioxide from the cells
4. Oxygen and Cellular Respiration
 Once they get into the cell going to mitochondria, energy occurs
by cellular respiration. The released energy is stored in the form of
ATP
A. Cells – “the smallest unit of Life”
 Humans made of billions of cells, all are identical made of the
same genetic makeup
 Multicellular- as different cells are doing different things making
us multicellular, different genes are expressed
 20,000 genes in total different cells will turn on different genes
making them specialize into whatever they will become

, I. Cells- “the smallest unit of Life”
-A. Cytology
1. Robert Hooke (1665)
- used light from the sun
A.2. Types of Microscopes
 2 lenses: Ocular lens at top of microscope & objective lenses (10x most common
eyepiece lens)
- Human Cheek Cells
 All cells are transparent unless it’s a plant cell due to chloroplast giving it it’s
green pigment
 Ex: Green is cytoskeleton and red is the nucleus
i. Compound Light Microscopes
 Tiny purple dots are prokaryotic- bacteria
 Light purple- eukaryotic cell
 Largest bacteria=Cyanobacterium
i. Electron Microscopy
Electron Microscope: shoots beams on the electrons,
electron sends out images
Two Types:
Transmission: Goes through the cell
Scanning: Getting the surface of the cell
I. Cells.A.3. Why are most cells small?
 As a cell increases in size, its volume
increases faster than its surface area
 Optimization of nutrients is why cells are so
small
Q: Surface to volume ratio of 6 or 1.2 is better for a cell?
 1.2, more surface to feed a smaller volume- smaller cells are able to obtain enough food
smaller cells have a larger surface to volume ratio, to feed a smaller volume

Cell Theory:
-Cell is the smallest unit of life, basic unit of life
- All cells arise from pre-existing cells
- all living organisms are composed of one or more cell

Prokaryotic Cells “Bacteria”
 Many can be colonial, living in groups
The most common shapes of prokaryotes:
1. Cocci- Circles (spherical)
2. Bacillus- Rod shaped
3. Spirochaete- spiral-shaped
ex: Lyme Disease- always by itself

, 4. Bacteria: The First Living Organism
Prokaryotic Cell
*Know structure of cell for test
 Capsule(yellow)slide#25 - typically being sugary will protect the bacteria from being
digested
 Bacteria attaches to surfaces all using pili to attach to the skin
 All prokaryotic organisms made of cell walls
 Gram positive – really thick cell wall
 Gram Negative- really thin cell wall
 Plasma Membrane- Double layer of phospholipids
 Plasmid- smaller piece of DNA, not a chromosome
- Resistant to antibiotics
Bacteria has one circular DNA and it tends to be attached to the plasma membrane
Resistance to antibiotics happens fast, can pass it to a plasmid very quick
Animal Cell (eukaryotic)
 Plasma Membrane- controls what comes in and out of the cell
 Cytosol – Fluid
 Cytoplasm- includes the organelles +fluid
Chromosomes never leave the nucleus unless the cell is dividing

ER- FACTORIES OF THE CELLS
Rough ER-(studded w/ ribosomes)- Produces proteins will be exported from the cell or can be
dangerous to the cell
Smooth ER- Some lipids will be made and more plasma membrane will be made here
Ribosomes- can be free in the cell or attached to the cell
Types of Organelles
 Golgi Apparatus- Modifies shaping and packing structure, where change will be
activated, synthesizes polysaccharides
 Mitochondria- Power house of the cell, glucose, proteins, carbs, and lipids all broken
down in the mitochondria to produce into energy (ATP)
 Lysosomes-(cleaners or trash keepers of the cell) digest food particles and mitochondria
that will stop functioning, can be dangerous as they have digestive enzymes
 Cytoskeleton- rods of proteins that gives the cell it’s shape
 Endo cytoskeleton- (internal skeleton) inside the cyto skeleton
 Centrioles- (made of protein) important role in animal cellular division
 spindle doesn’t form in animal cells if you take centrioles out

Test Q: Prokaryotic cells lack?
- Endoplasmic Reticulum (ER)