B2 Flashcards
where is palisade mesophyll cell found and what type of shape are they and what do they contain?
what do the chloroplasts do?
-They are found in leaves
-Rectangular box shaped cells that contain chloroplasts
-Chloroplasts are able to absorb large amount of light for photosynthesis.They also move around the cytoplastm in order to maximise the amount light absorbed
what does multi cellular mean?
how are multicellular organisms organised?
-Multi cellular means that they are made from billions of cell
-by:
-specialised cells
-tissues
-organs
-organ systems
-organisms
what are the palisade cells surrounded by?
what else do they have?
-Surrounded by a plasma membrane and a cell wall made of cellulose.This helps to protect the cell and keep it rigid.
-They also have a large vacoule to maintain turgor pressure(plasma membrane it pushes against the cell wall of the plaint to maintain its rigid structure)
where is root hair cell found?
what are there long hair-like extensions called and what do they do?
what are 2 things the cells have and explain why?
-Found at the plant’s roots near the growing tip
-Long hair like extensions are called root hairs
-These root hairs increase the surface area to maximise the movement of water and minerals fromt the soil into the plant root
-The cells have thin cellulose walls and a vacoule containing cell sap with a low water potential.This encourages the movement of water into the cell.
what are sperm cells?
what are 2 features of this?
-Sperm cells are male gametes in animals.
-They have a tail-like structure called undulipodium so they can move
-They also contain many mitochondria to supply the energy needed for this movement
in the human sperm how long is the mid piece of the tail and the sperm head?
what is fertilisation aka the sperms function?
-Mid piece of the tail is 7um long and the end is approximately 40um in length
-The sperm head is 3um wide and 4um long
-It is made up of an acrosome which contains digestive enzymes the enzymes are released when the sperm meets the egg to digest the protective layer and allow to penetrate.
-The sperms function is to deliver genetic information to the egg or ovum
what is egg cell?
what is the main thing it contains?
what is zona pellucida?
what is corona radiaa?
-Receives genetic material from the male and provides nutrients to developing an embryo designed to be fertilised
-Haploid genome to combine with male genetic material forming dipolid genome
-It contains nucleus which houses the genetic material
-Zona pellucida contains many glycoproteins which sperm cells recognise and re drawn to it
-Corona radiata heavy protein layer which provides nutrients for the egg and early embryo
what shape is the red blood cell how does it help it?
why are they flexible?
what is their function?
why do they not have a nucleus?
-The red blood cell is biconcave shape it increases the surface area to volume ratio of a RBC.
-They are flexible so that they can squeeze through narrow blood capillaries
-Their function is to transport oxygen around the body
-They don’t have a nucleus this increases space for the haemoglobin molecules inside the cell that carry oxygen
what is the function of white blood cells?
what is the neutrophil type of WBC?
-Function is designed to protect the body against bacterial and fungal infections
-Neutrophils: type of white blood cell which has essential role in our immune system.They are multi- lobed nucluei which enbales them to squeeze through small gaps when travelling to the site of infection.The cytoplasm contains lysosomes that contains enzymes which are used to digest pathogens that are ingested by neutrophil
what is lymphocytes?
what is phagocytes?
-Lymphocytes contain many ribosomes due to their role in antibody and antitoxins.They produce an immune response that destroys and remembers specific infections and pathogens
-Another type are phagocytes with an adaptable cytoskeleton that can change the shape of the enscapulation of foreign substances globular shaped
-B lymphocytes recognise antigens secrete antibodies/antitoxins
-T lymphocytes detect cancerous cells by the antigen receptors
-Helper t cells release cytokines which regulate white blood cells
what is the process of phagocytosis?
1)Pathogen is recognised as a foreign
2)Pathogen attached to the phagocyte by antibody and surface receptors
3)Engulfed by phagocyte by endocytosis-invagination of plasma membrane to form a phagosome
4)Lysosomes fuse to phagosomes
5)Release h2 02 hcl free radicals into phagosome
6)Digest pathogen-harmless products removed or used by phagocyte
7)start immune system phagocyte displays antigenic components
