lec 1- study of cell biology

Question 1

what is a cell?

Answer 1

The basic microscopic unit of all living beings, cells produce energy and use it to to build all the substances necessary for its life

Question 2

what is an organ?

Answer 2

a fully differentiated structural and functional unit in an animal that is specialized for some particular function

Question 3

what are tissues?

Answer 3

cells that aggregate to form a specific function

Question 4

how were cells discovered?

Answer 4

they were discovered after the invention of the microscope in 1865 by Robert Hooke, named cells after the similarity to cells that monks in monastery’s lived in

Question 5

State the cell theory:

Answer 5

1. All organisms are composed of one or more cells
2. The cell is the structural unit of life
3. cells arise only by division from a pre-existing cell

Question 6

do cells from different species share similar structure, composition, and metabolic features that have been conserved throughout evolution?

Answer 6

Yes

Question 7

organisms are built according to what?

Answer 7

organisms are built according to information encoded in a collection of genes

Question 8

why is the molecular structure of genes important?

Answer 8

the molecular structure of genes is important because it allows for changes in genetic information that lead to variation among individuals, which forms the basis of biological evolution

Question 9

if all cells contain identical copies of DNA in an organism, what causes the DNA to differentiate?

Answer 9

development from a single fertilized egg

Question 10

how do cells reproduce?

Answer 10

by division known as mitosis and meiosis

Question 11

what happens to the cell before division?

Answer 11

DNA replication

Question 12

how do animal cells derive energy?

Answer 12

Animal cells derive energy from the products of photosynthesis, convert glucose to ATP

Question 13

what do all chemical changes that occur in a cell require?

Answer 13

enzymes

Question 14

what does the sum total of chemical reactions in a cell represent?

Answer 14

the cells metabolism

Question 15

how do vesicles move?

Answer 15

by travelling on microtubules with the help of motor proteins (kinesin)

Question 16

how do cells respond to stimuli?

Answer 16

by the help of receptors

Question 17

what are the methods of response a cell does to respond to stimuli?

Answer 17

altering metabolism, moving from one place to another, or even committing suicide

Question 18

where did cells evolve from?

Answer 18

don’t know but all living organisms evolved from the last universal common ancestor LUCA

Question 19

what are the similarities between eukaryotes and prokaryotes?

Answer 19

many common structural features, an identical genetic language, a common set of metabolic pathways

Question 20

what are the model organism requirements, and what are the common ones?

Answer 20

relatively simple species, fast generation time, large number of offspring, easy to manipulate, inexpensive to breathing. mouse (mammal), fruit fly (insect), mustard plant (plant), zebra fish (fish), elegans (nematode), E. coli (bacterium), and saccharomyces (yeast)

Question 21

what is the cell size limited to?

Answer 21

the volume of cytoplasm that can be supported by the genes, the volume of cytoplasm that can be supported by exchange of nutrients, by the distance substances can efficiently travel through cytoplasm via diffusion

Question 22

what are the units cells are measured in?

Answer 22

nano or micro meters

Question 23

what is a hypothesis?

Answer 23

a statement consistent with most data, must me testable

Question 24

what is a theory?

Answer 24

a hypothesis that has been extensively tested , widely accepted

Question 25

what is a law?

Answer 25

a statement of fact of a natural phenomena that has been tested and confirmed