Biology Honours Exam 15 Jan 2010 (Dr S Datta)

Transcript

1 Biology Honours Exam 15 Jan 2010 (Dr S Datta) First to see cells. He was looking at cork and noted a great many boxes (1665) Observed living cells in pond water, which he called "animalcules" (1673) 1

2 Theodore Schwann - Zoologist who observed that the tissues of animals had cells (1839) Mattias Schleiden - Botanist, observed that the tissues of plants contained cells (1845) Reported that every living thing is made of up vital units, known as cells. He also predicted that cells come from other cells (1850 ) 2

3 Cell Theory 1. Every living organism is made of one or more cells. 2. The cell is the basic unit of structure and function. It is the smallest unit that can perform life functions. 3. All cells arise from 3

4 Cell Features Almost all cells contain: Ribosomes where are synthesized Cytoplasm semi-fluidic material DNA material in the Cytoskeleton cell s Cell Membrane outer boundary, some molecules can cell membrane 4

5 Comprehension Checkpoint True or false 1.Robert Hooke was the first person to see cells. 2.Bacterial cells do not have a cell membrane. 3.Cell Theory was developed by one scientist. 4.Plant cells have cytoplasm but no ribosome. 5.Cells taken from fungi may not have DNA. 6.Cells can only come from pre-existing cells. 7.It only took 5 years to develop the Cell Theory. 5

6 Prokaryotic Cells May be the very first cells to inhabit the earth Simple cells Bacteria These cells do NOT DNA may be circular and contained in Some bacteria have a tail-like structure called a flagella, that helps it to move. A capsule surrounds some bacteria and helps them avoid the body s immune system 6

7 Eukaryotic Cells Cells in plants, animals, protists, fungi Cell composed of 4 main parts 1.C 2.C 3.N 4.O 7

8 Nucleus Usually found the cell Has a nuclear, nuclear and Contains an organelle called the which makes the ribosomes 8

9 Cell Organelles this is the of the cell. It generates energy in the form of. often referred to as the powerhouse of the cell. 9

10 Cell Organelles processes, packages and secretes proteins. Comparable to a factory or assembly line (car assembly) 10

11 Cell Organelles contains e enzymes that breaks down proteins or other macro-molecules. Transport (intracellular highway). Ribosomess are positioned along the ER. Proteins made in the ribosomes enter the ER if transport is necessary. 11

12 Cytoskeleton Contains micro and micro CELL MEMBRANE regulates what is allowed to enter the cell and what is exported or leaves the cell Composed of a double layer of with embedded (receptors, enzymes) 12

13 Protein Production 1. holds the code to build most proteins 2. The blueprint is first transcribed to 3. Instructions are then transferred to 4. Ribosomes assemble proteins from 5. may travel through endoplasmic reticulum 6. apparatus may modify and/or tag proteins 13

14 PLANT CELL PLANT CELL Identify the parts 14

15 Differences between Prokaryotic and Eukaryotic Cells Feature Prokaryote Eukaryote Size Genetic material Organelles Cell walls Ribosome s 70s 80s 15

16 DNA consists of two molecules that are arranged into a ladder-like structure called a A molecule of DNA is made up of millions of tiny subunits called Each nucleotide consists of: 1. P 2. P 3. N 16

17 Label each figure: This is a Nucleo 17

18 This is a 18

19 Name the Purines and Pyrimidines A T C G 19

20 Create a DNA Sequencee A T Complementarity C T C G A G A T G C T A 20

21 DNA Function Gene is a section of DNA that codes for a. Each gene has a unique sequence of. This unique sequence of bases will code for the production of a protein. It is these proteins and combination of proteins that give us a unique Βιολογψ Ηονουρσ Εξαµινατιον 15 ϑαν, 2010 ( ρ αττα, ΜΗΣ) 21

22 Genome Gene DNA Fill in the boxes and also Answer these questions: What is the CENTRAL DOGMA? How did it change? Who changed it? mrna Trait 22

23 Amino acids have the general structure : R H 2 N-C-COOH H What is the amine group? Which one is the carboxyl group? Name the amino acids: R = H R = CH3 Draw the structure of Glycine and Alanine Show how you can connect Glycine and Alanine to form a di-peptide In joining two amino acids, what do you lose? How many amino acids are there in a protein? Where are proteins made inside the cell? Can proteins cause genetic diseases? Βιολογψ Ηονουρσ Εξαµινατιον 15 ϑαν, 2010 ( ρ αττα, ΜΗΣ) 23

24 What does this graph and reaction represent? Explain the process that is shown in this graph. 24 Βιολογψ Ηονουρσ Εξαµινατιον 15 ϑαν, 2010 ( ρ αττα, ΜΗΣ)