2.1 cell function by SAS
description
Transcript of 2.1 cell function by SAS
![Page 1: 2.1 cell function by SAS](https://reader036.fdocuments.us/reader036/viewer/2022062706/5576d71fd8b42a87588b4947/html5/thumbnails/1.jpg)
CHAPTER 2 : CELL STRUCTURE &
CELL ORGANISATION
2.1 Cell Structure & Function2.2 Cell Organisation
![Page 2: 2.1 cell function by SAS](https://reader036.fdocuments.us/reader036/viewer/2022062706/5576d71fd8b42a87588b4947/html5/thumbnails/2.jpg)
2.1 CELL STRUCTURE & FUNCTION
Learning Outcomes :1. Draw & label an animal cell and a plant
cell2. Identify the cellular components of an
animal cell & a plant cell3. State the functions of the cellular
components in an animal and a plant cell4. Compare & contrast an animal cell with a
plant cell5. Relate the density of certain organelles
with the functions of specific cells.
![Page 3: 2.1 cell function by SAS](https://reader036.fdocuments.us/reader036/viewer/2022062706/5576d71fd8b42a87588b4947/html5/thumbnails/3.jpg)
![Page 4: 2.1 cell function by SAS](https://reader036.fdocuments.us/reader036/viewer/2022062706/5576d71fd8b42a87588b4947/html5/thumbnails/4.jpg)
HISTORY Robert Hooke (1665) was first
discovered the cell structure of plant
He examined fine slices of cork with a primitive microscope
He saw many ‘box-like’ structures , then he called ‘cells’, from Latin for ‘little rooms’.
![Page 5: 2.1 cell function by SAS](https://reader036.fdocuments.us/reader036/viewer/2022062706/5576d71fd8b42a87588b4947/html5/thumbnails/5.jpg)
THE CELL THEORY(Schleiden M & Schwann T)
All living organisms are made up of one or more cells
New cells are formed by the division of pre-existing cells
Cells contain genetic material of an organism which is passed from the parent cells to daughter cells
Cells are the basic unit of structure & function in living things
![Page 6: 2.1 cell function by SAS](https://reader036.fdocuments.us/reader036/viewer/2022062706/5576d71fd8b42a87588b4947/html5/thumbnails/6.jpg)
![Page 7: 2.1 cell function by SAS](https://reader036.fdocuments.us/reader036/viewer/2022062706/5576d71fd8b42a87588b4947/html5/thumbnails/7.jpg)
![Page 8: 2.1 cell function by SAS](https://reader036.fdocuments.us/reader036/viewer/2022062706/5576d71fd8b42a87588b4947/html5/thumbnails/8.jpg)
ORGANELLES specialised structures which are each surrounded by its own membrane & perform specific function
![Page 9: 2.1 cell function by SAS](https://reader036.fdocuments.us/reader036/viewer/2022062706/5576d71fd8b42a87588b4947/html5/thumbnails/9.jpg)
PLASMA MEMBRANE
Thin, semi-permeable Made of protein, lipid Controls the
movement of substances in and out of the cell
Non-organelle
![Page 10: 2.1 cell function by SAS](https://reader036.fdocuments.us/reader036/viewer/2022062706/5576d71fd8b42a87588b4947/html5/thumbnails/10.jpg)
CYTOPLASM Jelly-like substance
that contains water & mineral salts
Contains organelles and food such as carbohydrates (glucose)
Medium for metabolic reactions
Supplies the substances required by organelles
Non-organelle
![Page 11: 2.1 cell function by SAS](https://reader036.fdocuments.us/reader036/viewer/2022062706/5576d71fd8b42a87588b4947/html5/thumbnails/11.jpg)
CELL WALL Thick layer outside
the plasma membrane Made up of cellulose,
fully permeable Maintains the shape
of the plant cells Provides mechanical
support Non-organelle
![Page 12: 2.1 cell function by SAS](https://reader036.fdocuments.us/reader036/viewer/2022062706/5576d71fd8b42a87588b4947/html5/thumbnails/12.jpg)
NUCLEUS Spherical shape with
double membrane Contains nucleolus,
chromosomes, nucleoplasm & nuclear membrane
Controls & regulates all the activities of cell
Contain the heredity factors responsible for the traits
![Page 13: 2.1 cell function by SAS](https://reader036.fdocuments.us/reader036/viewer/2022062706/5576d71fd8b42a87588b4947/html5/thumbnails/13.jpg)
RIBOSOME Small particles
consisting of RNA Exists freely in the
cytoplasm or on the surface of the endoplasmic reticulum
Synthesis of protein
![Page 14: 2.1 cell function by SAS](https://reader036.fdocuments.us/reader036/viewer/2022062706/5576d71fd8b42a87588b4947/html5/thumbnails/14.jpg)
ENDOPLASMIC RETICULUM A system of membrane-
enclosed tubules closely packed together and continuous with the nuclear membrane
RER has ribosome, SER does not have
Transport system for protein & lipids within the cell
RER transport protein to other part of cell
SER stimulates the synthesis of lipids & cholesterol & transport within the cell
![Page 15: 2.1 cell function by SAS](https://reader036.fdocuments.us/reader036/viewer/2022062706/5576d71fd8b42a87588b4947/html5/thumbnails/15.jpg)
![Page 16: 2.1 cell function by SAS](https://reader036.fdocuments.us/reader036/viewer/2022062706/5576d71fd8b42a87588b4947/html5/thumbnails/16.jpg)
GOLGI APPARATUS Vacuolar region
surrounded by a complex meshwork of vesicles budding off at its end
Received protein & lipids from ER & modify them to form specific secretion such as enzymes & hormones
Pack the secretions formed into secreting vesicles & transport them to plasma membrane to be secreted
Controls the secretory activity of cells
Formation of lysosomes
![Page 17: 2.1 cell function by SAS](https://reader036.fdocuments.us/reader036/viewer/2022062706/5576d71fd8b42a87588b4947/html5/thumbnails/17.jpg)
![Page 18: 2.1 cell function by SAS](https://reader036.fdocuments.us/reader036/viewer/2022062706/5576d71fd8b42a87588b4947/html5/thumbnails/18.jpg)
VACUOLE Filled with cell sap,
surrounded by semi-permeable membrane called the tonoplast
Contain water, sugar & dissolved minerals
Maintain turgidity of cells in plants
![Page 19: 2.1 cell function by SAS](https://reader036.fdocuments.us/reader036/viewer/2022062706/5576d71fd8b42a87588b4947/html5/thumbnails/19.jpg)
MITOCHONDRIA Rod-shape with a
double membrane Outer membrane is
smooth, inner membrane is folded to form cristae
Known as ‘power-house’ of the cell
Releases energy as it is the site for aerobic respiration
![Page 20: 2.1 cell function by SAS](https://reader036.fdocuments.us/reader036/viewer/2022062706/5576d71fd8b42a87588b4947/html5/thumbnails/20.jpg)
![Page 21: 2.1 cell function by SAS](https://reader036.fdocuments.us/reader036/viewer/2022062706/5576d71fd8b42a87588b4947/html5/thumbnails/21.jpg)
CHLOROPLAST Disc-shape organelle
with a double membrane
Consist of an orderly arrangement of grana within the stroma. Granum contains chlorophyll
Site of photosynthesis Trapped light energy
and change it into chemical energy
![Page 22: 2.1 cell function by SAS](https://reader036.fdocuments.us/reader036/viewer/2022062706/5576d71fd8b42a87588b4947/html5/thumbnails/22.jpg)
LYSOSOMES Membrane-bound
vesicles found in animal cells
Contain enzymes which control breakdown of protein & lipids
Contain enzymes that digest aged or defective cell components or materials taken in by the cell from its environments such as food particles or bacteria.
![Page 23: 2.1 cell function by SAS](https://reader036.fdocuments.us/reader036/viewer/2022062706/5576d71fd8b42a87588b4947/html5/thumbnails/23.jpg)
CENTRIOLES A pair of small
cylindrical structures (microtubules)
Form spindle fibre for cell division
![Page 24: 2.1 cell function by SAS](https://reader036.fdocuments.us/reader036/viewer/2022062706/5576d71fd8b42a87588b4947/html5/thumbnails/24.jpg)
COMPARE & CONTRAST
ANIMAL CELL SIMILARITIES PLANT CELL
A plasma membrane surrounding the cytoplasm
Both contain nucleus & cytoplasm
Both contain organelles such as mitochondria, ER, Golgi apparatus &
ribosomes
![Page 25: 2.1 cell function by SAS](https://reader036.fdocuments.us/reader036/viewer/2022062706/5576d71fd8b42a87588b4947/html5/thumbnails/25.jpg)
ANIMAL CELL DIFFERENCES PLANT CELLSmaller than plant
cellSIZE Larger than animal
cellIrregular shape SHAPE Often regular in
shapeAbsent CELL WALL PresentAbsent CHLOROPLAST Present
No large vacuoles. If present, small &
numerous.
VACUOLES Large central vacuole filled with
cell sapIn a form of glycogen
in liver & muscle tissues
FOOD STORAGE In a form of starch
Present CENTRIOLES AbsentSome animal cell
have cilia or flagellaCILIA & FLAGELLA Absent
![Page 26: 2.1 cell function by SAS](https://reader036.fdocuments.us/reader036/viewer/2022062706/5576d71fd8b42a87588b4947/html5/thumbnails/26.jpg)
RELATIONSHIP BETWEEN THE STRUCTURE OF AN ANIMAL CELL
& A PLANT CELL
![Page 27: 2.1 cell function by SAS](https://reader036.fdocuments.us/reader036/viewer/2022062706/5576d71fd8b42a87588b4947/html5/thumbnails/27.jpg)
The number of specific organelles in a cell varies on the type of cell and its function.
Active cell many mitochondria to provide enough energy for its activities. Eg. : sperm cells, flight muscle cell (insects & birds)
Cell in meristems of plant shoot & root
Green plants more chloroplasts to carry out photosynthesis such as palisade mesophyll cells and spongy mesophyll cells, also guard cells.
![Page 28: 2.1 cell function by SAS](https://reader036.fdocuments.us/reader036/viewer/2022062706/5576d71fd8b42a87588b4947/html5/thumbnails/28.jpg)
EXERCISE 2.11. What are the organelle structures of a
cell?
2. What are the functions of each structure describe above?
![Page 29: 2.1 cell function by SAS](https://reader036.fdocuments.us/reader036/viewer/2022062706/5576d71fd8b42a87588b4947/html5/thumbnails/29.jpg)