10 CMH Human and Social Biology CELLS Crated by Reynaldo Thomas.

10 CMH 10 CMH Human and Social Biology Human and Social Biology

CELLS CELLS

Crated by Reynaldo ThomasCrated by Reynaldo Thomas

GENERAL OBJECTIVES

At the end of this lesson students should : Be cognizant that all organisms are made up from cell. Be cognizant of unspecialized plant and animal cells. Identify cell organelles.

SPECIFIC OBJECTIVES

At the end of this lesson students should be able to :Tell the importance of cells.Draw simple diagram of unspecialized cells in plant and animal. Label and state the functions of each cell components.

The cellThe cell All organisms are made up of simple

basic units called cells.

Most cells are too small to be seen by the naked eye.

Their structure only visible when viewed with a microscope.

The Structure of cellsThe Structure of cells

Organisms, such as bacteria and amoeba are unicellular, consisting

of a single cell.

They are able to carry out all the functions needed to sustain life.

Example respiration, nutrition and Reproduction.

Most plants and animals are multicellular

They have different types of cell organized into tissues and then organs.

The cells are specialized to carry out specific functions.

Specialized Cells In The Human BodySpecialized Cells In The Human Body While many cells make up simple body

parts, such as tissues, some complete more complex and specialized tasks.

These specialized cells are specially designed to perform the functions for which they are intended.

Each of these cell types are formed and operate differently, ensuring that the cell can carry out the necessary body function that it is intended to complete. Example red blood cells, white blood cells Example red blood cells, white blood cells and nerve cells. and nerve cells.

Nerve cells

A nerve cell is like a receiver, transmitter and transmission line with the task of passing a signal.

Conducts nerve impulses.

Specialized cells of the human body

Epithelial cell Line the cavities and surfaces of

structures in the body

Form many glands

it help in secretion, selective absorption and protection

Sperm cell Specialize to fertilize egg.

the tail allows the sperm cell to swim towards the female sex cell.

Egg cells Have a large nucleus containing genetic

information from the female.

Store food in the cytoplasm.

Red Blood Cells

Transport oxygen from lungs to the body cells for cellular respiration.

Haemoglobin of the cytoplasm carries the oxygen.

White Blood CellWhite Blood Cell Also called leucocytes Have a nucleus

White blood cells destroys bacteria Two types phagocytes and lymphocytes

Phagocytes engulf microorganisms in a process called phagocytosis.

Lymphocytes produce antibodies which kill microorganisms.

Muscle Cell

These cells contract so that movement can take place at joints.

Muscle cells are long.

Specialized Plant Cells

Root hair Cell Absorbs minerals and water from the water in

the soil.

The cell’s surface area is increase by the long root hair.

Xylem Vessel

Transport water throughout the plant.

This cell has no cytoplasm.

Unspecialized cells

1. Without specialty or specialization.

2. Having no special function and found in all multi cellular organisms.

The Structure of cells The Structure of cells Animal cellAnimal cell Has a irregular shape

Do not usually have vacuoles but if present, they are very small.

Cell membrane surrounding the cell contents.

Plant cell Plant cells has a rectangular shape.

Have all the components of Animal cells and other parts.

Cell Organelles Forms the boundary between the cell

contents and the surroundings. Control the movement of substances into

and out of the cell. Cytoplasm

All cell activities take place here.

Contains the cell organelles for example mitochondria and ribosomes.

Nucleus This is where chromosomes are found

The nucleus controls the cell’s activities.

Mitochondrion This is where cellular respiration take

place.

Where energy for cell activities are release.

Cells which are more active contain more mitochondria.

Cell wall This is a non-living layer outside of plants

cell membrane.

The cell wall allow substances to pass through it freely.

Vacuole Large in plant cells and contain water (cell

sap).

Small and sometimes not permanent in animal cells.

Chloroplast

The green pigment chlorophyll is found in it.

This is where photosynthesis take place. Not found in animal cells.

Differences Between Plant And Animal CellDifferences Between Plant And Animal Cell

Cell Parts Animal cell Plant cell

Shape Irregular shape Rectangular shape

Cell wall No cell wall Cell wall present

Vacuole small vacuole large vacuole

Chloroplast No chloroplast Chloroplast present

Chlorophyll No chlorophyll Chlorophyll present